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{{task}}
A [http://mathworld.wolfram.com/NarcissisticNumber.html Narcissistic decimal number] is a non-negative integer, , that is equal to the sum of the -th powers of each of the digits in the decimal representation of , where is the number of digits in the decimal representation of .
Narcissistic (decimal) numbers are sometimes called '''Armstrong''' numbers, named after Michael F. Armstrong.
They are also known as '''Plus Perfect''' numbers.
;An example: ::::* if is '''153''' ::::* then , (the number of decimal digits) is '''3''' ::::* we have 13 + 53 + 33 = 1 + 125 + 27 = '''153''' ::::* and so '''153''' is a narcissistic decimal number
;Task: Generate and show here the first '''25''' narcissistic decimal numbers.
Note: , the first in the series.
;See also:
- the OEIS entry: [http://oeis.org/A005188 Armstrong (or Plus Perfect, or narcissistic) numbers].
- MathWorld entry: [http://mathworld.wolfram.com/NarcissisticNumber.html Narcissistic Number].
- Wikipedia entry: [https://en.wikipedia.org/wiki/Narcissistic_number Narcissistic number].
Ada
with Ada.Text_IO;
procedure Narcissistic is
function Is_Narcissistic(N: Natural) return Boolean is
Decimals: Natural := 1;
M: Natural := N;
Sum: Natural := 0;
begin
while M >= 10 loop
M := M / 10;
Decimals := Decimals + 1;
end loop;
M := N;
while M >= 1 loop
Sum := Sum + (M mod 10) ** Decimals;
M := M/10;
end loop;
return Sum=N;
end Is_Narcissistic;
Count, Current: Natural := 0;
begin
while Count < 25 loop
if Is_Narcissistic(Current) then
Ada.Text_IO.Put(Integer'Image(Current));
Count := Count + 1;
end if;
Current := Current + 1;
end loop;
end Narcissistic;
{{out}}
0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315
Agena
Tested with Agena 2.9.5 Win32
scope
# print the first 25 narcissistic numbers
local power := reg( 0, 1, 1, 1, 1, 1, 1, 1, 1, 1 );
local count := 0;
local maxCount := 25;
local candidate := 0;
local prevDigits := 0;
local digits := 1;
for d9 from 0 to 2 while count < maxCount do
if d9 > 0 and digits < 9 then digits := 9 fi;
for d8 from 0 to 9 while count < maxCount do
if d8 > 0 and digits < 8 then digits := 8 fi;
for d7 from 0 to 9 while count < maxCount do
if d7 > 0 and digits < 7 then digits := 7 fi;
for d6 from 0 to 9 while count < maxCount do
if d6 > 0 and digits < 6 then digits := 6 fi;
for d5 from 0 to 9 while count < maxCount do
if d5 > 0 and digits < 5 then digits := 5 fi;
for d4 from 0 to 9 while count < maxCount do
if d4 > 0 and digits < 4 then digits := 4 fi;
for d3 from 0 to 9 while count < maxCount do
if d3 > 0 and digits < 3 then digits := 3 fi;
for d2 from 0 to 9 while count < maxCount do
if d2 > 0 and digits < 2 then digits := 2 fi;
for d1 from 0 to 9 do
if prevDigits <> digits then
# number of digits has increased - increase the powers
prevDigits := digits;
for i from 2 to 9 do mul power[ i + 1 ], i od;
fi;
# sum the digits'th powers of the digits of candidate
local sum := power[ d1 + 1 ] + power[ d2 + 1 ] + power[ d3 + 1 ]
+ power[ d4 + 1 ] + power[ d5 + 1 ] + power[ d6 + 1 ]
+ power[ d7 + 1 ] + power[ d8 + 1 ] + power[ d9 + 1 ]
;
if candidate = sum
then
# found another narcissistic decimal number
io.write( " ", candidate );
inc count, 1
fi;
inc candidate, 1
od; # d1
od; # d2
od; # d3
od; # d4
od; # d5
od; # d6
od; # d7
od; # d8
od; # d9
io.writeline()
epocs
{{out}}
0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315
ALGOL 68
# find some narcissistic decimal numbers #
# returns TRUE if n is narcissitic, FALSE otherwise; n should be >= 0 #
PROC is narcissistic = ( INT n )BOOL:
BEGIN
# count the number of digits in n #
INT digits := 0;
INT number := n;
WHILE digits +:= 1;
number OVERAB 10;
number > 0
DO SKIP OD;
# sum the digits'th powers of the digits of n #
INT sum := 0;
number := n;
TO digits DO
sum +:= ( number MOD 10 ) ^ digits;
number OVERAB 10
OD;
# n is narcissistic if n = sum #
n = sum
END # is narcissistic # ;
# print the first 25 narcissistic numbers #
INT count := 0;
FOR n FROM 0 WHILE count < 25 DO
IF is narcissistic( n ) THEN
# found another narcissistic number #
print( ( " ", whole( n, 0 ) ) );
count +:= 1
FI
OD;
print( ( newline ) )
{{out}}
0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315
ALGOL W
{{Trans|Agena}}
begin
% print the first 25 narcissistic numbers %
integer array power( 0 :: 9 );
integer count, candidate, prevDigits, digits;
power( 0 ) := 0;
for i := 1 until 9 do power( i ) := 1;
count := 0;
candidate := 0;
prevDigits := 0;
digits := 1;
for d9 := 0 until 2 do begin
if d9 > 0 and digits < 9 then digits := 9;
for d8 := 0 until 9 do begin
if d8 > 0 and digits < 8 then digits := 8;
for d7 := 0 until 9 do begin
if d7 > 0 and digits < 7 then digits := 7;
for d6 := 0 until 9 do begin
if d6 > 0 and digits < 6 then digits := 6;
for d5 := 0 until 9 do begin
if d5 > 0 and digits < 5 then digits := 5;
for d4 := 0 until 9 do begin
if d4 > 0 and digits < 4 then digits := 4;
for d3 := 0 until 9 do begin
if d3 > 0 and digits < 3 then digits := 3;
for d2 := 0 until 9 do begin
if d2 > 0 and digits < 2 then digits := 2;
for d1 := 0 until 9 do begin
integer number, sum;
if prevDigits <> digits then begin
% number of digits has increased %
% - increase the powers %
prevDigits := digits;
for i := 2 until 9 do power( i ) := power( i ) * i;
end;
% sum the digits'th powers of the %
% digits of candidate %
sum := power( d1 ) + power( d2 ) + power( d3 )
+ power( d4 ) + power( d5 ) + power( d6 )
+ power( d7 ) + power( d8 ) + power( d9 )
;
if candidate = sum then begin
% found another narcissistic %
% decimal number %
writeon( i_w := 1, s_w := 1, candidate );
count := count + 1;
if count >= 25 then goto done
end;
candidate := candidate + 1
end d1;
end d2;
end d3;
end d4;
end d5;
end d6;
end d7;
end d8;
end d9;
done:
write()
end.
{{out}}
0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315
AppleScript
{{Trans|JavaScript}} {{Trans|Haskell}} AppleScript is a little out of its depth here, even with an algorithm which restricts the search space (see the JavaScript and Haskell discussions).
The full 7 digit search that finds the 25th number takes nearly 14 minutes on the system here (four seconds to scan the 5 digit combinations, and find the first 20, and 103 seconds to scan the six digit combinations for the first 21 narcissi).
(For comparison, equivalent code in JavaScript returns all 25 numbers in about 120 milliseconds)
-- NARCISSI -------------------------------------------------------------------
-- isDaffodil :: Int -> Int -> Bool
on isDaffodil(e, n)
set ds to digitList(n)
(e = length of ds) and (n = powerSum(e, ds))
end isDaffodil
-- digitList :: Int -> [Int]
on digitList(n)
if n > 0 then
{n mod 10} & digitList(n div 10)
else
{}
end if
end digitList
-- powerSum :: Int -> [Int] -> Int
on powerSum(e, ns)
script
on |λ|(a, x)
a + x ^ e
end |λ|
end script
foldl(result, 0, ns) as integer
end powerSum
-- narcissiOfLength :: Int -> [Int]
on narcissiOfLength(nDigits)
script nthPower
on |λ|(x)
{x, x ^ nDigits as integer}
end |λ|
end script
set powers to map(nthPower, enumFromTo(0, 9))
script combn
on digitTree(n, parents)
if n > 0 then
if parents ≠ {} then
script nextLayer
on |λ|(pair)
set {digit, intSum} to pair
script addPower
on |λ|(dp)
set {d, p} to dp
{d, p + intSum}
end |λ|
end script
map(addPower, items 1 thru (digit + 1) of powers)
end |λ|
end script
set nodes to concatMap(nextLayer, parents)
else
set nodes to powers
end if
digitTree(n - 1, nodes)
else
script
on |λ|(pair)
isDaffodil(nDigits, item 2 of pair)
end |λ|
end script
filter(result, parents)
end if
end digitTree
end script
script snd
on |λ|(ab)
item 2 of ab
end |λ|
end script
map(snd, combn's digitTree(nDigits, {}))
end narcissiOfLength
-- TEST -----------------------------------------------------------------------
on run
{0} & concatMap(narcissiOfLength, enumFromTo(1, 5))
-- 4 seconds, 20 narcissi
-- {0} & concatMap(narcissiOfLength, enumFromTo(1, 6))
-- 103 seconds, 21 narcissi
-- {0} & concatMap(narcissiOfLength, enumFromTo(1, 7))
-- 13.75 minutes, 25 narcissi
end run
-- GENERIC FUNCTIONS ----------------------------------------------------------
-- concatMap :: (a -> [b]) -> [a] -> [b]
on concatMap(f, xs)
set lst to {}
set lng to length of xs
tell mReturn(f)
repeat with i from 1 to lng
set lst to (lst & |λ|(item i of xs, i, xs))
end repeat
end tell
return lst
end concatMap
-- enumFromTo :: Int -> Int -> [Int]
on enumFromTo(m, n)
if n < m then
set d to -1
else
set d to 1
end if
set lst to {}
repeat with i from m to n by d
set end of lst to i
end repeat
return lst
end enumFromTo
-- filter :: (a -> Bool) -> [a] -> [a]
on filter(f, xs)
tell mReturn(f)
set lst to {}
set lng to length of xs
repeat with i from 1 to lng
set v to item i of xs
if |λ|(v, i, xs) then set end of lst to v
end repeat
return lst
end tell
end filter
-- foldl :: (a -> b -> a) -> a -> [b] -> a
on foldl(f, startValue, xs)
tell mReturn(f)
set v to startValue
set lng to length of xs
repeat with i from 1 to lng
set v to |λ|(v, item i of xs, i, xs)
end repeat
return v
end tell
end foldl
-- map :: (a -> b) -> [a] -> [b]
on map(f, xs)
tell mReturn(f)
set lng to length of xs
set lst to {}
repeat with i from 1 to lng
set end of lst to |λ|(item i of xs, i, xs)
end repeat
return lst
end tell
end map
-- Lift 2nd class handler function into 1st class script wrapper
-- mReturn :: Handler -> Script
on mReturn(f)
if class of f is script then
f
else
script
property |λ| : f
end script
end if
end mReturn
{{Out}}
{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 153, 370, 371, 407, 1634, 8208, 9474, 54748, 92727, 93084, 548834, 1741725, 4210818, 9800817, 9926315}
AutoHotkey
#NoEnv ; Do not try to use environment variables
SetBatchLines, -1 ; Execute as quickly as you can
StartCount := A_TickCount
Narc := Narc(25)
Elapsed := A_TickCount - StartCount
MsgBox, Finished in %Elapsed%ms`n%Narc%
return
Narc(m)
{
Found := 0, Lower := 0
Progress, B2
Loop
{
Max := 10 ** Digits:=A_Index
Loop, 10
Index := A_Index-1, Powers%Index% := Index**Digits
While Lower < Max
{
Sum := 0
Loop, Parse, Lower
Sum += Powers%A_LoopField%
Loop, 10
{
if (Lower + (Index := A_Index-1) == Sum + Powers%Index%)
{
Out .= Lower+Index . (Mod(++Found,5) ? ", " : "`n")
Progress, % Found/M*100
if (Found >= m)
{
Progress, Off
return Out
}
}
}
Lower += 10
}
}
}
{{out}}
Finished in 17690ms
0, 1, 2, 3, 4
5, 6, 7, 8, 9
153, 370, 371, 407, 1634
8208, 9474, 54748, 92727, 93084
548834, 1741725, 4210818, 9800817, 9926315
This is a derivative of the python example, but modified for speed reasons.
Instead of summing all the powers of all the numbers at once, we sum the powers for this multiple of 10, then check each number 0 through 9 at once before summing the next multiple of 10. This way, we don't have to calculate the sum of 174172_ for every number 1741720 through 1741729.
AWK
# syntax: GAWK -f NARCISSISTIC_DECIMAL_NUMBER.AWK
BEGIN {
for (n=0;;n++) {
leng = length(n)
sum = 0
for (i=1; i<=leng; i++) {
c = substr(n,i,1)
sum += c ^ leng
}
if (n == sum) {
printf("%d ",n)
if (++count == 25) { break }
}
}
exit(0)
}
output:
0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315
Befunge
This can take several minutes to complete in most interpreters, so it's probably best to use a compiler if you want to see the full sequence.
p55*\>:>:>:55+%\55+/00gvv_@
>1>+>^v\_^#!:<p01p00:+1<>\>
>#-_>\>20p110g>\20g*\v>1-v|
^!p00:-1g00+$_^#!:<-1<^\.:<
{{out}}
0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315
C
For a much longer but faster solution, see [[Narcissistic decimal number/C]].
The following prints the first 25 numbers, though not in order...
#include <stdio.h>
#include <gmp.h>
#define MAX_LEN 81
mpz_t power[10];
mpz_t dsum[MAX_LEN + 1];
int cnt[10], len;
void check_perm(void)
{
char s[MAX_LEN + 1];
int i, c, out[10] = { 0 };
mpz_get_str(s, 10, dsum[0]);
for (i = 0; s[i]; i++) {
c = s[i]-'0';
if (++out[c] > cnt[c]) return;
}
if (i == len)
gmp_printf(" %Zd", dsum[0]);
}
void narc_(int pos, int d)
{
if (!pos) {
check_perm();
return;
}
do {
mpz_add(dsum[pos-1], dsum[pos], power[d]);
++cnt[d];
narc_(pos - 1, d);
--cnt[d];
} while (d--);
}
void narc(int n)
{
int i;
len = n;
for (i = 0; i < 10; i++)
mpz_ui_pow_ui(power[i], i, n);
mpz_init_set_ui(dsum[n], 0);
printf("length %d:", n);
narc_(n, 9);
putchar('\n');
}
int main(void)
{
int i;
for (i = 0; i <= 10; i++)
mpz_init(power[i]);
for (i = 1; i <= MAX_LEN; i++) narc(i);
return 0;
}
{{out}}
length 1: 9 8 7 6 5 4 3 2 1 0
length 2:
length 3: 407 371 370 153
length 4: 9474 8208 1634
length 5: 93084 92727 54748
length 6: 548834
length 7: 9926315 9800817 4210818 1741725
length 8: 88593477 24678051 24678050
length 9: 912985153 534494836 472335975 146511208
length 10: 4679307774
length 11: 94204591914 82693916578 49388550606 44708635679 42678290603 40028394225 32164049651 32164049650
length 12:
length 13:
length 14: 28116440335967
length 15:
length 16: 4338281769391371 4338281769391370
length 17: 35875699062250035 35641594208964132 21897142587612075
length 18:
^C
C++
#include <iostream>
#include <vector>
using namespace std;
typedef unsigned int uint;
class NarcissisticDecs
{
public:
void makeList( int mx )
{
uint st = 0, tl; int pwr = 0, len;
while( narc.size() < mx )
{
len = getDigs( st );
if( pwr != len )
{
pwr = len;
fillPower( pwr );
}
tl = 0;
for( int i = 1; i < 10; i++ )
tl += static_cast<uint>( powr[i] * digs[i] );
if( tl == st ) narc.push_back( st );
st++;
}
}
void display()
{
for( vector<uint>::iterator i = narc.begin(); i != narc.end(); i++ )
cout << *i << " ";
cout << "\n\n";
}
private:
int getDigs( uint st )
{
memset( digs, 0, 10 * sizeof( int ) );
int r = 0;
while( st )
{
digs[st % 10]++;
st /= 10;
r++;
}
return r;
}
void fillPower( int z )
{
for( int i = 1; i < 10; i++ )
powr[i] = pow( static_cast<float>( i ), z );
}
vector<uint> narc;
uint powr[10];
int digs[10];
};
int main( int argc, char* argv[] )
{
NarcissisticDecs n;
n.makeList( 25 );
n.display();
return system( "pause" );
}
{{out}}
0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315
C#
using System;
namespace Narcissistic
{
class Narcissistic
{
public bool isNarcissistic(int z)
{
if (z < 0) return false;
string n = z.ToString();
int t = 0, l = n.Length;
foreach (char c in n)
t += Convert.ToInt32(Math.Pow(Convert.ToDouble(c - 48), l));
return t == z;
}
}
class Program
{
static void Main(string[] args)
{
Narcissistic n = new Narcissistic();
int c = 0, x = 0;
while (c < 25)
{
if (n.isNarcissistic(x))
{
if (c % 5 == 0) Console.WriteLine();
Console.Write("{0,7} ", x);
c++;
}
x++;
}
Console.WriteLine("\n\nPress any key to continue...");
Console.ReadKey();
}
}
}
{{out}}
0 1 2 3 4
5 6 7 8 9
153 370 371 407 1634
8208 9474 54748 92727 93084
548834 1741725 4210818 9800817 9926315
or
//Narcissistic numbers: Nigel Galloway: February 17th., 2015
using System;
using System.Collections.Generic;
using System.Linq;
namespace RC {
public static class NumberEx {
public static IEnumerable<int> Digits(this int n) {
List<int> digits = new List<int>();
while (n > 0) {
digits.Add(n % 10);
n /= 10;
}
return digits.AsEnumerable();
}
}
class Program {
static void Main(string[] args) {
foreach (int N in Enumerable.Range(0, Int32.MaxValue).Where(k => {
var digits = k.Digits();
return digits.Sum(x => Math.Pow(x, digits.Count())) == k;
}).Take(25)) {
System.Console.WriteLine(N);
}
}
}
}
{{out}}
0
1
2
3
4
5
6
7
8
9
153
370
371
407
1634
8208
9474
54748
92727
93084
548834
1741725
4210818
9800817
9926315
All 89 terms
{{libheader|System.Numerics}}
{{trans|FreeBASIC}} (FreeBASIC, GMP version)
Why stop at 25? Even using '''ulong''' instead of '''int''' only gets one to the 44th item. The 89th (last) item has 39 digits, which '''BigInteger''' easily handles. Of course, the BigInteger implementation is slower than native data types. But one can compensate a bit by calculating in parallel. Not bad, it can get all 89 items in under 7 1/2 minutes on a core i7. The calculation to the 25th item takes a fraction of a second. The calculation for all items up to 25 digits long (67th item) takes about half a minute with sequential processing and less than a quarter of a minute using parallel processing. Note that parallel execution involves some overhead, and isn't a time improvement unless computing around 15 digits or more. This program can test all numbers up to 61 digits in under half an hour, of course the highest item found has only 39 digits.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using System.Numerics;
static class Program
{
public static void nar(int max, bool only1 = false)
{
int n, n1, n2, n3, n4, n5, n6, n7, n8, n9;
int[] d; // digits tally
char [] bs; // BigInteger String
List<BigInteger> res = new List<BigInteger>(); // per n digits results
BigInteger[,] p = new BigInteger[10, max + 1]; // powers array
// BigIntegers for intermediate results
BigInteger x2, x3, x4, x5, x6, x7, x8, x9;
for (n = only1 ? max : 1; n <= max; n++) // main loop
{
for (int i = 1; i <= 9; i++) // init powers array for this n
{
p[i, 1] = BigInteger.Pow(i, n);
for (int j = 2; j <= n; j++) p[i, j] = p[i, 1] * j;
}
for (n9 = n; n9 >= 0; n9--) // nested loops...
{
x9 = p[9, n9];
for (n8 = n - n9; n8 >= 0; n8--)
{
x8 = x9 + p[8, n8];
for (n7 = n - n9 - n8; n7 >= 0; n7--)
{
x7 = x8 + p[7, n7];
for (n6 = n - n9 - n8 - n7; n6 >= 0; n6--)
{
x6 = x7 + p[6, n6];
for (n5 = n - n9 - n8 - n7 - n6; n5 >= 0; n5--)
{
x5 = x6 + p[5, n5];
for (n4 = n - n9 - n8 - n7 - n6 - n5; n4 >= 0; n4--)
{
x4 = x5 + p[4, n4];
for (n3 = n - n9 - n8 - n7 - n6 - n5 - n4; n3 >= 0; n3--)
{
x3 = x4 + p[3, n3];
for (n2 = n - n9 - n8 - n7 - n6 - n5 - n4 - n3; n2 >= 0; n2--)
{
x2 = x3 + p[2, n2];
for (n1 = n - n9 - n8 - n7 - n6 - n5 - n4 - n3 - n2; n1 >= 0; n1--)
{
bs = (x2 + n1).ToString().ToCharArray();
switch (bs.Length.CompareTo(n))
{ // Since all the for/next loops step down, when the digit count
// becomes smaller than n, it's time to try the next n value.
case -1: { goto Next_n; }
case 0:
{
d = new int[10]; foreach (char c in bs) d[c - 48] += 1;
if (n9 == d[9] && n8 == d[8] && n7 == d[7] &&
n6 == d[6] && n5 == d[5] && n4 == d[4] &&
n3 == d[3] && n2 == d[2] && n1 == d[1] &&
n - n9 - n8 - n7 - n6 - n5 - n4 - n3 - n2 - n1 == d[0])
res.Add(BigInteger.Parse(new string(bs)));
break;
}
}
}
}
}
}
}
}
}
}
}
Next_n: if (only1) {
Console.Write("{0} ", n); lock (resu) resu.AddRange(res); return;
} else {
res.Sort(); Console.WriteLine("{2,3} {0,3}: {1}",
Math.Ceiling((DateTime.Now - st).TotalSeconds), string.Join(" ", res), n); res.Clear();
}
}
}
private static DateTime st = default(DateTime);
private static List<BigInteger> resu = new List<BigInteger>();
private static bool para = true; // parallel (default) or sequential calcualtion
private static int lim = 7; // this is the number of digits to calcualate, not the nth entry.
// for up to the 25th item, use lim = 7 digits.
// for all 89 items, use lim = 39 digits.
public static void Main(string[] args)
{
if (args.Count() > 0)
{
int t = lim; int.TryParse(args[0], out t);
if (t < 1) t = 1; // number of digits must be > 0
if (t > 61) t = 61; // no point when lim * math.pow(9, lim) < math.pow(10, lim - 1)
lim = t;
// default is parallel, will do sequential when any 2nd command line parameter is present.
para = !(args.Count() > 1);
}
st = DateTime.Now;
if (para)
{
Console.Write("Calculations in parallel... "); // starts the bigger ones first
Parallel.ForEach(Enumerable.Range(1, lim).Reverse().ToArray(), n => { nar(n, true); } );
resu.Sort(); int[] g = Enumerable.Range(1, resu.Count).ToArray();
var both = g.Zip(resu, (a, b) => a.ToString() + " " + b.ToString());
Console.WriteLine("\n{0}", string.Join("\n", both));
}
else { Console.WriteLine("Sequential calculations:"); nar(lim); }
Console.WriteLine("Total elasped: {0} seconds", (DateTime.Now - st).TotalSeconds);
if (System.Diagnostics.Debugger.IsAttached) Console.ReadKey();
}
}
{{out}}(with command line parameter = "39")
Calculations in parallel... 7 6 5 4 3 2 1 11 10 9 8 15 14 13 12 19 18 17 16 23 22 20 21 26 27 25 24 30 31 29 34 28 35 38 33 39 32 37 36 1 0 2 1 3 2 4 3 5 4 6 5 7 6 8 7 9 8 10 9 11 153 12 370 13 371 14 407 15 1634 16 8208 17 9474 18 54748 19 92727 20 93084 21 548834 22 1741725 23 4210818 24 9800817 25 9926315 26 24678050 27 24678051 28 88593477 29 146511208 30 472335975 31 534494836 32 912985153 33 4679307774 34 32164049650 35 32164049651 36 40028394225 37 42678290603 38 44708635679 39 49388550606 40 82693916578 41 94204591914 42 28116440335967 43 4338281769391370 44 4338281769391371 45 21897142587612075 46 35641594208964132 47 35875699062250035 48 1517841543307505039 49 3289582984443187032 50 4498128791164624869 51 4929273885928088826 52 63105425988599693916 53 128468643043731391252 54 449177399146038697307 55 21887696841122916288858 56 27879694893054074471405 57 27907865009977052567814 58 28361281321319229463398 59 35452590104031691935943 60 174088005938065293023722 61 188451485447897896036875 62 239313664430041569350093 63 1550475334214501539088894 64 1553242162893771850669378 65 3706907995955475988644380 66 3706907995955475988644381 67 4422095118095899619457938 68 121204998563613372405438066 69 121270696006801314328439376 70 128851796696487777842012787 71 174650464499531377631639254 72 177265453171792792366489765 73 14607640612971980372614873089 74 19008174136254279995012734740 75 19008174136254279995012734741 76 23866716435523975980390369295 77 1145037275765491025924292050346 78 1927890457142960697580636236639 79 2309092682616190307509695338915 80 17333509997782249308725103962772 81 186709961001538790100634132976990 82 186709961001538790100634132976991 83 1122763285329372541592822900204593 84 12639369517103790328947807201478392 85 12679937780272278566303885594196922 86 1219167219625434121569735803609966019 87 12815792078366059955099770545296129367 88 115132219018763992565095597973971522400 89 115132219018763992565095597973971522401 Total elasped: 443.8791684 seconds ``` (without any command line parameters)Calculations in parallel... 1 3 2 4 5 7 6 1 0 2 1 3 2 4 3 5 4 6 5 7 6 8 7 9 8 10 9 11 153 12 370 13 371 14 407 15 1634 16 8208 17 9474 18 54748 19 92727 20 93084 21 548834 22 1741725 23 4210818 24 9800817 25 9926315 Total elasped: 0.0279259 seconds ``` (with command line parameters= "7 x")Sequential calculations: 1 1: 0 1 2 3 4 5 6 7 8 9 2 1: 3 1: 153 370 371 407 4 1: 1634 8208 9474 5 1: 54748 92727 93084 6 1: 548834 7 1: 1741725 4210818 9800817 9926315 Total elasped: 0.0175957 seconds ``` (with command line parameters= "25 x")Sequential calculations: 1 1: 0 1 2 3 4 5 6 7 8 9 2 1: 3 1: 153 370 371 407 4 1: 1634 8208 9474 5 1: 54748 92727 93084 6 1: 548834 7 1: 1741725 4210818 9800817 9926315 8 1: 24678050 24678051 88593477 9 1: 146511208 472335975 534494836 912985153 10 1: 4679307774 11 1: 32164049650 32164049651 40028394225 42678290603 44708635679 49388550606 82693916578 94204591914 12 1: 13 1: 14 1: 28116440335967 15 1: 16 1: 4338281769391370 4338281769391371 17 2: 21897142587612075 35641594208964132 35875699062250035 18 3: 19 4: 1517841543307505039 3289582984443187032 4498128791164624869 4929273885928088826 20 6: 63105425988599693916 21 9: 128468643043731391252 449177399146038697307 22 12: 23 17: 21887696841122916288858 27879694893054074471405 27907865009977052567814 28361281321319229463398 35452590104031691935943 24 23: 174088005938065293023722 188451485447897896036875 239313664430041569350093 25 31: 1550475334214501539088894 1553242162893771850669378 3706907995955475988644380 3706907995955475988644381 4422095118095899619457938 Total elasped: 30.5658944 seconds ``` ## Clojure Find N first Narcissistic numbers. ```Clojure (ns narcissistic.core (:require [clojure.math.numeric-tower :as math])) (defn digits [n] ;; digits of a number. (->> n str (map (comp read-string str)))) (defn narcissistic? [n] ;; True if the number is a Narcissistic one. (let [d (digits n) s (count d)] (= n (reduce + (map #(math/expt % s) d))))) (defn firstNnarc [n] ;;list of the first "n" Narcissistic numbers. (take n (filter narcissistic? (range)))) ``` {{out}} by Average-user ```txt (time (doall (firstNnarc 25))) "Elapsed time: 186430.429966 msecs" (0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315) ``` ## COBOL ```COBOL PROGRAM-ID. NARCISSIST-NUMS. DATA DIVISION. WORKING-STORAGE SECTION. 01 num-length PIC 9(2) value 0. 01 in-sum PIC 9(9) value 0. 01 counter PIC 9(9) value 0. 01 current-number PIC 9(9) value 0. 01 narcissist PIC Z(9). 01 temp PIC 9(9) value 0. 01 modulo PIC 9(9) value 0. 01 answer PIC 9 . PROCEDURE DIVISION. MAIN-PROCEDURE. DISPLAY "the first 20 narcissist numbers:" . MOVE 20 TO counter. PERFORM UNTIL counter=0 PERFORM 000-NARCISSIST-PARA IF answer = 1 SUBTRACT 1 from counter GIVING counter MOVE current-number TO narcissist DISPLAY narcissist END-IF ADD 1 TO current-number END-PERFORM STOP RUN. 000-NARCISSIST-PARA. MOVE ZERO TO in-sum. MOVE current-number TO temp. COMPUTE num-length =1+ FUNCTION Log10(temp) PERFORM UNTIL temp=0 DIVIDE temp BY 10 GIVING temp REMAINDER modulo COMPUTE modulo=modulo**num-length ADD modulo to in-sum GIVING in-sum END-PERFORM. IF current-number=in-sum MOVE 1 TO answer ELSE MOVE 0 TO answer END-IF. END PROGRAM NARCISSIST-NUMS. ``` {{out}} ```txt the first 20 narcissist numbers: 0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 ``` ## Common Lisp ```lisp (defun integer-to-list (n) (map 'list #'digit-char-p (prin1-to-string n))) (defun narcissisticp (n) (let* ((lst (integer-to-list n)) (e (length lst))) (= n (reduce #'+ (mapcar (lambda (x) (expt x e)) lst))))) (defun start () (loop for c from 0 while (< narcissistic 25) counting (narcissisticp c) into narcissistic do (if (narcissisticp c) (print c)))) ``` {{out}} ```txt CL-USER> (start) 0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315 NIL ``` ## D ### Simple Version ```d void main() { import std.stdio, std.algorithm, std.conv, std.range; immutable isNarcissistic = (in uint n) pure @safe => n.text.map!(d => (d - '0') ^^ n.text.length).sum == n; writefln("%(%(%d %)\n%)", uint.max.iota.filter!isNarcissistic.take(25).chunks(5)); } ``` {{out}} ```txt 0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315 ``` ### Fast Version {{trans|Python}} ```d import std.stdio, std.algorithm, std.range, std.array; uint[] narcissists(in uint m) pure nothrow @safe { typeof(return) result; foreach (immutable uint digits; 0 .. 10) { const digitPowers = 10.iota.map!(i => i ^^ digits).array; foreach (immutable uint n; 10 ^^ (digits - 1) .. 10 ^^ digits) { uint digitPSum, div = n; while (div) { digitPSum += digitPowers[div % 10]; div /= 10; } if (n == digitPSum) { result ~= n; if (result.length >= m) return result; } } } assert(0); } void main() { writefln("%(%(%d %)\n%)", 25.narcissists.chunks(5)); } ``` With LDC2 compiler prints the same output in less than 0.3 seconds. ### Faster Version {{trans|C}} ```d import std.stdio, std.bigint, std.conv; struct Narcissistics(TNum, uint maxLen) { TNum[10] power; TNum[maxLen + 1] dsum; uint[10] count; uint len; void checkPerm() const { uint[10] mout; immutable s = dsum[0].text; foreach (immutable d; s) { immutable c = d - '0'; if (++mout[c] > count[c]) return; } if (s.length == len) writef(" %d", dsum[0]); } void narc2(in uint pos, uint d) { if (!pos) { checkPerm; return; } do { dsum[pos - 1] = dsum[pos] + power[d]; count[d]++; narc2(pos - 1, d); count[d]--; } while (d--); } void show(in uint n) { len = n; foreach (immutable i, ref p; power) p = TNum(i) ^^ n; dsum[n] = 0; writef("length %d:", n); narc2(n, 9); writeln; } } void main() { enum maxLength = 16; Narcissistics!(ulong, maxLength) narc; //Narcissistics!(BigInt, maxLength) narc; // For larger numbers. foreach (immutable i; 1 .. maxLength + 1) narc.show(i); } ``` {{out}} ```txt length 1: 9 8 7 6 5 4 3 2 1 0 length 2: length 3: 407 371 370 153 length 4: 9474 8208 1634 length 5: 93084 92727 54748 length 6: 548834 length 7: 9926315 9800817 4210818 1741725 length 8: 88593477 24678051 24678050 length 9: 912985153 534494836 472335975 146511208 length 10: 4679307774 length 11: 94204591914 82693916578 49388550606 44708635679 42678290603 40028394225 32164049651 32164049650 length 12: length 13: length 14: 28116440335967 length 15: length 16: 4338281769391371 4338281769391370 ``` With LDC2 compiler and maxLength=16 the run-time is about 0.64 seconds. ## Elixir {{trans|D}} ```elixir defmodule RC do def narcissistic(m) do Enum.reduce(1..10, [0], fn digits,acc -> digitPowers = List.to_tuple(for i <- 0..9, do: power(i, digits)) Enum.reduce(power(10, digits-1) .. power(10, digits)-1, acc, fn n,result -> sum = divsum(n, digitPowers, 0) if n == sum do if length(result) == m-1, do: throw Enum.reverse(result, [n]) [n | result] else result end end) end) end defp divsum(0, _, sum), do: sum defp divsum(n, digitPowers, sum) do divsum(div(n,10), digitPowers, sum+elem(digitPowers,rem(n,10))) end defp power(n, m), do: power(n, m, 1) defp power(_, 0, pow), do: pow defp power(n, m, pow), do: power(n, m-1, pow*n) end try do RC.narcissistic(25) catch x -> IO.inspect x end ``` {{out}} ```txt [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 153, 370, 371, 407, 1634, 8208, 9474, 54748, 92727, 93084, 548834, 1741725, 4210818, 9800817, 9926315] ``` ## ERRE ```ERRE PROGRAM NARCISISTIC !$DOUBLE BEGIN N=0 LOOP C$=MID$(STR$(N),2) LENG=LEN(C$) SUM=0 FOR I=1 TO LENG DO C=VAL(MID$(C$,I,1)) SUM+=C^LENG END FOR IF N=SUM THEN PRINT(N;) COUNT=COUNT+1 EXIT IF COUNT=25 END IF N=N+1 END LOOP END PROGRAM ``` Output ```txt 0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315 ``` =={{header|F Sharp|F#}}== ```fsharp //Naïve solution of Narcissitic number: Nigel Galloway - Febryary 18th., 2015 open System let rec _Digits (n,g) = if n < 10 then n::g else _Digits(n/10,n%10::g) seq{0 .. Int32.MaxValue} |> Seq.filter (fun n -> let d = _Digits (n, []) d |> List.fold (fun a l -> a + int ((float l) ** (float (List.length d)))) 0 = n) |> Seq.take(25) |> Seq.iter (printfn "%A") ``` {{out}} ```txt 0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315 ``` ## FactorUSING: io kernel lists lists.lazy math math.functions math.text.utils prettyprint sequences ; IN: rosetta-code.narcissistic-decimal-number : digit-count ( n -- count ) log10 floor >integer 1 + ; : narcissist? ( n -- ? ) dup [ 1 digit-groups ] [ digit-count [ ^ ] curry ] bi map-sum = ; : first25 ( -- seq ) 25 0 lfrom [ narcissist? ] lfilter ltake list>array ; : main ( -- ) first25 [ pprint bl ] each ; MAIN: main ``` {{out}} ```txt 0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315 ``` ## Forth {{works with|GNU Forth|0.7.0}} ```forth : dig.num \ returns input number and the number of its digits ( n -- n n1 ) dup 0 swap begin swap 1 + swap dup 10 >= while 10 / repeat drop ; : zero.divmod \ /mod that returns zero if number is zero dup 0 = if drop 0 else /mod then ; : zero.div \ division that returns zero if divisor is zero dup 0 = if drop else / then ; : next.last depth 2 - roll ; \ gets next-to-last number from the stack : ten.to \ ( n -- 10^n ) returns 1 for zero and negative dup 0 <= if drop 1 else dup 1 = if drop 10 else 10 swap 1 do 10 * loop then then ; : split.div \ returns input number and its digits ( n -- n n1 n2 n3....) dup 10 < if dup else \ duplicates single digit numbers dig.num \ provides number of digits swap dup rot dup 1 - ten.to swap \ stack juggling, ten raised to number of digits - 1... 1 do \ ... is the needed divisor, counter on top and ... dup rot swap zero.divmod swap rot 10 / \ ...division loop loop drop then ; : to.pow \ nth power of positive numbers ( n m -- n^m ) swap dup rot dup 0 <= if 2drop drop 1 else 0 do swap dup rot * loop swap zero.div then ; : num.pow \ raises each digit to the power of (number of digits) depth 1 - 0 do next.last depth 1 - to.pow loop ; : add.num depth 2 > if begin + depth 2 = until then ; : narc.check split.div num.pow add.num ; : narc.num 0 { a b } \ ( m -- n1 n2 n3 ... nm ) page \ displays m narcissistic decimal numbers... 999999999 0 do \ ...beginning with 0 a b = if leave then i narc.check = if i . cr b 1 + to b then loop ; 25 narc.num ``` {{out}} ```txt 0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315 ok ``` ## FreeBASIC ### Simple Version ```FreeBASIC ' normal version: 14-03-2017 ' compile with: fbc -s console ' can go up to 18 digits (ulongint is 64bit), above 18 overflow will occur Dim As Integer n, n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, a, b Dim As Integer d() Dim As ULongInt d2pow(0 To 9) = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9} Dim As ULongInt x Dim As String str_x For n = 1 To 7 For n9 = n To 0 Step -1 For n8 = n-n9 To 0 Step -1 For n7 = n-n9-n8 To 0 Step -1 For n6 = n-n9-n8-n7 To 0 Step -1 For n5 = n-n9-n8-n7-n6 To 0 Step -1 For n4 = n-n9-n8-n7-n6-n5 To 0 Step -1 For n3 = n-n9-n8-n7-n6-n5-n4 To 0 Step -1 For n2 = n-n9-n8-n7-n6-n5-n4-n3 To 0 Step -1 For n1 = n-n9-n8-n7-n6-n5-n4-n3-n2 To 0 Step -1 n0 = n-n9-n8-n7-n6-n5-n4-n3-n2-n1 x = n1 + n2*d2pow(2) + n3*d2pow(3) + n4*d2pow(4) + n5*d2pow(5)_ + n6*d2pow(6) + n7*d2pow(7) + n8*d2pow(8) + n9*d2pow(9) str_x = Str(x) If Len(str_x) = n Then ReDim d(10) For a = 0 To n-1 d(Str_x[a]- Asc("0")) += 1 Next a If n0 = d(0) AndAlso n1 = d(1) AndAlso n2 = d(2) AndAlso n3 = d(3)_ AndAlso n4 = d(4) AndAlso n5 = d(5) AndAlso n6 = d(6)_ AndAlso n7 = d(7) AndAlso n8 = d(8) AndAlso n9 = d(9) Then Print x End If End If Next n1 Next n2 Next n3 Next n4 Next n5 Next n6 Next n7 Next n8 Next n9 For a As Integer = 2 To 9 d2pow(a) = d2pow(a) * a Next a Next n ' empty keyboard buffer While InKey <> "" : Wend Print : Print "hit any key to end program" Sleep End ``` {{out}} ```txt 9 8 7 6 5 4 3 2 1 0 407 371 370 153 9474 8208 1634 93084 92727 54748 548834 9926315 9800817 4210818 1741725 ``` ### GMP Version ```txt It takes about 35 min. to find all 88 numbers (39 digits). To go all the way it takes about 2 hours. ``` ```FreeBASIC ' gmp version: 17-06-2015 ' uses gmp ' compile with: fbc -s console #Include Once "gmp.bi" ' change the number after max for the maximum n-digits you want (2 to 61) #Define max 61 Dim As Integer n, n0, n1, n2, n3, n4, n5, n6, n7, n8, n9 Dim As Integer i, j Dim As UInteger d() Dim As ZString Ptr gmp_str gmp_str = Allocate(100) ' create gmp integer array, Dim d2pow(9, max) As Mpz_ptr ' initialize array and set start value, For i = 0 To 9 For j = 0 To max d2pow(i, j) = Allocate(Len(__mpz_struct)) : Mpz_init(d2pow(i, j)) Next j Next i ' gmp integers for to hold intermediate result Dim As Mpz_ptr x1 = Allocate(Len(__mpz_struct)) : Mpz_init(x1) Dim As Mpz_ptr x2 = Allocate(Len(__mpz_struct)) : Mpz_init(x2) Dim As Mpz_ptr x3 = Allocate(Len(__mpz_struct)) : Mpz_init(x3) Dim As Mpz_ptr x4 = Allocate(Len(__mpz_struct)) : Mpz_init(x4) Dim As Mpz_ptr x5 = Allocate(Len(__mpz_struct)) : Mpz_init(x5) Dim As Mpz_ptr x6 = Allocate(Len(__mpz_struct)) : Mpz_init(x6) Dim As Mpz_ptr x7 = Allocate(Len(__mpz_struct)) : Mpz_init(x7) Dim As Mpz_ptr x8 = Allocate(Len(__mpz_struct)) : Mpz_init(x8) For n = 1 To max For i = 1 To 9 'Mpz_set_ui(d2pow(i,0), 0) Mpz_ui_pow_ui(d2pow(i,1), i, n) For j = 2 To n Mpz_mul_ui(d2pow(i, j), d2pow(i, 1), j) Next j Next i For n9 = n To 0 Step -1 For n8 = n-n9 To 0 Step -1 Mpz_add(x8, d2pow(9, n9), d2pow(8, n8)) For n7 = n-n9-n8 To 0 Step -1 Mpz_add(x7, x8, d2pow(7, n7)) For n6 = n-n9-n8-n7 To 0 Step -1 Mpz_add(x6, x7, d2pow(6, n6)) For n5 = n-n9-n8-n7-n6 To 0 Step -1 Mpz_add(x5, x6, d2pow(5, n5)) For n4 = n-n9-n8-n7-n6-n5 To 0 Step -1 Mpz_add(x4, x5, d2pow(4, n4)) For n3 = n-n9-n8-n7-n6-n5-n4 To 0 Step -1 Mpz_add(x3, x4, d2pow(3, n3)) For n2 = n-n9-n8-n7-n6-n5-n4-n3 To 0 Step -1 Mpz_add(x2, x3, d2pow(2, n2)) For n1 = n-n9-n8-n7-n6-n5-n4-n3-n2 To 0 Step -1 Mpz_add_ui(x1, x2, n1) n0 = n-n9-n8-n7-n6-n5-n4-n3-n2-n1 Mpz_get_str(gmp_str, 10, x1) If Len(*gmp_str) = n Then ReDim d(10) For i = 0 To n-1 d(gmp_str[i] - Asc("0")) += 1 Next i If n9 = d(9) AndAlso n8 = d(8) AndAlso n7 = d(7) AndAlso n6 = d(6)_ AndAlso n5 = d(5) AndAlso n4 = d(4) AndAlso n3 = d(3)_ AndAlso n2 = d(2) AndAlso n1 = d(1) AndAlso n0 = d(0) Then Print *gmp_str End If ElseIf Len(*gmp_str) < n Then ' all for next loops have a negative step value ' if len(str_x) becomes smaller then n it's time to try the next n value ' GoTo label1 ' old school BASIC ' prefered FreeBASIC style Exit For, For, For, For, For, For, For, For, For ' leave n1, n2, n3, n4, n5, n6, n7, n8, n9 loop ' and continue's after next n9 End If Next n1 Next n2 Next n3 Next n4 Next n5 Next n6 Next n7 Next n8 Next n9 ' label1: Next n ' empty keyboard buffer While InKey <> "" : Wend Print : Print "hit any key to end program" Sleep End ``` {{out}} Left side: program output, right side: sorted on length, value 9 0 8 1 7 2 6 3 5 4 4 5 3 6 2 7 1 8 0 9 407 153 371 370 370 371 153 407 9474 1634 8208 8208 1634 9474 93084 54748 92727 92727 54748 93084 548834 548834 9926315 1741725 9800817 4210818 4210818 9800817 1741725 9926315 88593477 24678050 24678051 24678051 24678050 88593477 912985153 146511208 534494836 472335975 472335975 534494836 146511208 912985153 4679307774 4679307774 94204591914 32164049650 82693916578 32164049651 49388550606 40028394225 44708635679 42678290603 42678290603 44708635679 40028394225 49388550606 32164049651 82693916578 32164049650 94204591914 28116440335967 28116440335967 4338281769391371 4338281769391370 4338281769391370 4338281769391371 35875699062250035 21897142587612075 35641594208964132 35641594208964132 21897142587612075 35875699062250035 4929273885928088826 1517841543307505039 4498128791164624869 3289582984443187032 3289582984443187032 4498128791164624869 1517841543307505039 4929273885928088826 63105425988599693916 63105425988599693916 449177399146038697307 128468643043731391252 128468643043731391252 449177399146038697307 35452590104031691935943 21887696841122916288858 28361281321319229463398 27879694893054074471405 27907865009977052567814 27907865009977052567814 27879694893054074471405 28361281321319229463398 21887696841122916288858 35452590104031691935943 239313664430041569350093 174088005938065293023722 188451485447897896036875 188451485447897896036875 174088005938065293023722 239313664430041569350093 4422095118095899619457938 1550475334214501539088894 3706907995955475988644381 1553242162893771850669378 3706907995955475988644380 3706907995955475988644380 1553242162893771850669378 3706907995955475988644381 1550475334214501539088894 4422095118095899619457938 177265453171792792366489765 121204998563613372405438066 174650464499531377631639254 121270696006801314328439376 128851796696487777842012787 128851796696487777842012787 121270696006801314328439376 174650464499531377631639254 121204998563613372405438066 177265453171792792366489765 23866716435523975980390369295 14607640612971980372614873089 19008174136254279995012734741 19008174136254279995012734740 19008174136254279995012734740 19008174136254279995012734741 14607640612971980372614873089 23866716435523975980390369295 2309092682616190307509695338915 1145037275765491025924292050346 1927890457142960697580636236639 1927890457142960697580636236639 1145037275765491025924292050346 2309092682616190307509695338915 17333509997782249308725103962772 17333509997782249308725103962772 186709961001538790100634132976991 186709961001538790100634132976990 186709961001538790100634132976990 186709961001538790100634132976991 1122763285329372541592822900204593 1122763285329372541592822900204593 12679937780272278566303885594196922 12639369517103790328947807201478392 12639369517103790328947807201478392 12679937780272278566303885594196922 1219167219625434121569735803609966019 1219167219625434121569735803609966019 12815792078366059955099770545296129367 12815792078366059955099770545296129367 115132219018763992565095597973971522401 115132219018763992565095597973971522400 115132219018763992565095597973971522400 115132219018763992565095597973971522401 ``` ## FunL ```funl def narcissistic( start ) = power = 1 powers = array( 0..9 ) def narc( n ) = num = n.toString() m = num.length() if power != m power = m powers( 0..9 ) = [i^m | i <- 0..9] if n == sum( powers(int(d)) | d <- num ) n # narc( n + 1 ) else narc( n + 1 ) narc( start ) println( narcissistic(0).take(25) ) ``` {{out}} ```txt [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 153, 370, 371, 407, 1634, 8208, 9474, 54748, 92727, 93084, 548834, 1741725, 4210818, 9800817, 9926315] ``` ## Go Nothing fancy as it runs in a fraction of a second as-is. ```go package main import "fmt" func narc(n int) []int { power := [...]int{0, 1, 2, 3, 4, 5, 6, 7, 8, 9} limit := 10 result := make([]int, 0, n) for x := 0; len(result) < n; x++ { if x >= limit { for i := range power { power[i] *= i // i^m } limit *= 10 } sum := 0 for xx := x; xx > 0; xx /= 10 { sum += power[xx%10] } if sum == x { result = append(result, x) } } return result } func main() { fmt.Println(narc(25)) } ``` {{out}} ```txt [0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315] ``` =={{header|GW-BASIC}}== {{trans|FreeBASIC}} Maximum for N (double) is14 digits, there are no 15 digits numbers ```qbasic 1 DEFINT A-W : DEFDBL X-Z : DIM D(9) : DIM X2(9) : KEY OFF : CLS 2 FOR A = 0 TO 9 : X2(A) = A : NEXT A 3 FOR N = 1 TO 7 4 FOR N9 = N TO 0 STEP -1 5 FOR N8 = N-N9 TO 0 STEP -1 6 FOR N7 = N-N9-N8 TO 0 STEP -1 7 FOR N6 = N-N9-N8-N7 TO 0 STEP -1 8 FOR N5 = N-N9-N8-N7-N6 TO 0 STEP -1 9 FOR N4 = N-N9-N8-N7-N6-N5 TO 0 STEP -1 10 FOR N3 = N-N9-N8-N7-N6-N5-N4 TO 0 STEP -1 11 FOR N2 = N-N9-N8-N7-N6-N5-N4-N3 TO 0 STEP -1 12 FOR N1 = N-N9-N8-N7-N6-N5-N4-N3-N2 TO 0 STEP -1 13 N0 = N-N9-N8-N7-N6-N5-N4-N3-N2-N1 14 X = N1 + N2*X2(2) + N3*X2(3) + N4*X2(4) + N5*X2(5) + N6*X2(6) + N7*X2(7) + N8*X2(8) + N9*X2(9) 15 S$ = MID$(STR$(X),2) 16 IF LEN(S$) < N THEN GOTO 25 17 IF LEN(S$) <> N THEN GOTO 24 18 FOR A = 0 TO 9 : D(A) = 0 : NEXT A 19 FOR A = 0 TO N-1 20 B = ASC(MID$(S$,A+1,1))-48 21 D(B) = D(B) + 1 22 NEXT A 23 IF N0 = D(0) AND N1 = D(1) AND N2 = D(2) AND N3 = D(3) AND N4 = D(4) AND N5 = D(5) AND N6 = D(6) AND N7 = D(7) AND N8 = D(8) AND N9 = D(9) THEN PRINT X, 24 NEXT N1 : NEXT N2 : NEXT N3 : NEXT N4 : NEXT N5 : NEXT N6 : NEXT N7 : NEXT N8 : NEXT N9 25 FOR A = 2 TO 9 26 X2(A) = X2(A) * A 27 NEXT A 28 NEXT N 29 PRINT 30 PRINT "done" 31 END ``` {{out}} ```txt 9 8 7 6 5 4 3 2 1 0 407 371 370 153 9474 8208 1634 93084 92727 54748 548834 9926315 9800817 4210818 1741725 ``` ## Haskell ===Exhaustive search (integer series)=== ```Haskell import Data.Char (digitToInt) isNarcissistic :: Int -> Bool isNarcissistic n = (sum ((^ digitCount) <$> digits) ==) n where digits = digitToInt <$> show n digitCount = length digits main :: IO () main = mapM_ print $ take 25 (filter isNarcissistic [0 ..]) ``` ===Reduced search (unordered digit combinations)=== As summing the nth power of the digits is unaffected by digit order, we can reduce the search space by filtering digit combinations of given length and arbitrary order, rather than filtering a full integer sequence. In this way we can find the 25th narcissistic number after '''length $ concatMap digitPowerSums [1 .. 7] == 19447''' tests – an improvement on the exhaustive trawl through '''9926315''' integers. ```haskell import Control.Arrow (second) isDaffodil :: Int -> Int -> Bool isDaffodil e n = let ds = digitList n in e == length ds && n == powerSum e ds powerSum :: Int -> [Int] -> Int powerSum n = foldr ((+) . (^ n)) 0 digitList :: Int -> [Int] digitList 0 = [] digitList n = rem n 10 : digitList (quot n 10) narcissiOfLength :: Int -> [Int] narcissiOfLength nDigits = snd <$> digitTree nDigits [] where powers = ((,) <*> (^ nDigits)) <$> [0 .. 9] digitTree n parents = if n > 0 then digitTree -- Power sums for all unordered digit combinations. (n - 1) -- (Digit order is irrelevant when summing powers) (if null parents then powers else concatMap (\(d, pwrSum) -> (second (pwrSum +) <$> take (d + 1) powers)) parents) else filter (isDaffodil nDigits . snd) parents main :: IO () main = print $ 0 : concatMap narcissiOfLength [1 .. 7] ``` {{Out}} ```txt [0,1,2,3,4,5,6,7,8,9,153,370,371,407,1634,8208,9474,54748,92727,93084,548834,1741725,4210818,9800817,9926315] ``` =={{header|Icon}} and {{header|Unicon}}== The following is a quick, dirty, and slow solution that works in both languages: ```unicon procedure main(A) limit := integer(A[1]) | 25 every write(isNarcissitic(seq(0))\limit) end procedure isNarcissitic(n) sn := string(n) m := *sn every (sum := 0) +:= (!sn)^m return sum = n end ``` Sample run: ```txt ->ndn 0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315 -> ``` ## J ```j getDigits=: "."0@": NB. get digits from number isNarc=: (= +/@(] ^ #)@getDigits)"0 NB. test numbers for Narcissism ``` '''Example Usage''' ```j (#~ isNarc) i.1e7 NB. display Narcissistic numbers 0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315 ``` ## Java {{works with|Java|1.5+}} ```java5 public class Narc{ public static boolean isNarc(long x){ if(x < 0) return false; String xStr = Long.toString(x); int m = xStr.length(); long sum = 0; for(char c : xStr.toCharArray()){ sum += Math.pow(Character.digit(c, 10), m); } return sum == x; } public static void main(String[] args){ for(long x = 0, count = 0; count < 25; x++){ if(isNarc(x)){ System.out.print(x + " "); count++; } } } } ``` {{out}} ```txt 0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315 ``` {{works with|Java|1.8}} The statics and the System.exit(0) stem from having first developed a version that is not limited by the amount of narcisstic numbers that are to be calculated. I then read that this is a criterion and thus the implementation is an afterthought and looks awkwardish... but still... works! ```java5 import java.util.stream.IntStream; public class NarcissisticNumbers { static int numbersToCalculate = 25; static int numbersCalculated = 0; public static void main(String[] args) { IntStream.iterate(0, n -> n + 1).limit(Integer.MAX_VALUE).boxed().forEach(i -> { int length = i.toString().length(); int addedDigits = 0; for (int count = 0; count < length; count++) { int value = Integer.parseInt(String.valueOf(i.toString().charAt(count))); addedDigits += Math.pow(value, length); } if (i == addedDigits) { numbersCalculated++; System.out.print(addedDigits + " "); } if (numbersCalculated == numbersToCalculate) { System.exit(0); } }); } } ``` {{out}} ```txt 0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315 ``` ## JavaScript ### ES5 {{trans|Java}} ```javascript function isNarc(x) { var str = x.toString(), i, sum = 0, l = str.length; if (x < 0) { return false; } else { for (i = 0; i < l; i++) { sum += Math.pow(str.charAt(i), l); } } return sum == x; } function main(){ var n = []; for (var x = 0, count = 0; count < 25; x++){ if (isNarc(x)){ n.push(x); count++; } } return n.join(' '); } ``` {{out}} ```txt "0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315" ``` ### ES6 ====Exhaustive search (integer series)==== ```JavaScript (() => { 'use strict'; // digits :: Int -> [Int] const digits = n => n.toString() .split('') .map(x => parseInt(x, 10)); // pow :: Int -> Int -> Int const pow = Math.pow; // isNarc :: Int -> Bool const isNarc = n => { const ds = digits(n), len = ds.length; return ds.reduce((a, x) => a + pow(x, len), 0) === n; }; // until :: (a -> Bool) -> (a -> a) -> a -> a const until = (p, f, x) => { let v = x; while (!p(v)) v = f(v); return v; }; return until( x => x.narc.length > 24, x => ({ n: x.n + 1, narc: (isNarc(x.n) ? x.narc.concat(x.n) : x.narc) }), { n: 0, narc: [] } ) .narc })(); ``` {{Out}} ```JavaScript [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 153, 370, 371, 407, 1634, 8208, 9474, 54748, 92727, 93084, 548834, 1741725, 4210818, 9800817, 9926315] ``` ====Reduced search (unordered digit combinations)==== {{Trans|Haskell}} As summing the nth power of the digits is unaffected by digit order, we can reduce the search space by filtering digit combinations of given length and arbitrary order, rather than filtering a full integer sequence. In this way we can find the 25th narcissistic number after '''length(concatMap(digitPowerSums, enumFromTo(0, 7))) === 19447''' tests – an improvement on the exhaustive trawl through '''9926315''' integers. (Generating the unordered digit combinations directly as power sums allows faster testing later, and needs less space) ```JavaScript (() => { 'use strict'; // DAFFODILS -------------------------------------------------------------- // narcissiOfLength :: Int -> [Int] const narcissiOfLength = n => n > 0 ? filter(curry(isDaffodil)(n), digitPowerSums(n)) : [0]; // Do the decimal digits of N, each raised to the power E, sum to N itself ? // isDaffodil :: Int -> Int -> Bool const isDaffodil = (e, n) => { const powerSum = (n, xs) => xs.reduce((a, x) => a + Math.pow(x, n), 0), digitList = n => (n > 0) ? ( cons((n % 10), digitList(Math.floor(n / 10))) ) : [], ds = digitList(n); return e === ds.length && n === powerSum(e, ds); }; // The subset of integers of n digits that actually need daffodil checking: // (Flattened leaves of a tree of unique digit combinations, in which // order is not significant. Digit sequence doesn't affect power summing) // digitPowerSums :: Int -> [Int] const digitPowerSums = nDigits => { const digitPowers = map(x => [x, pow(x, nDigits)], enumFromTo(0, 9)), treeGrowth = (n, parentPairs) => (n > 0) ? ( treeGrowth(n - 1, isNull(parentPairs) ? ( digitPowers ) : concatMap(([parentDigit, parentSum]) => map(([leafDigit, leafSum]) => // [leafDigit, parentSum + leafSum], take(parentDigit + 1, digitPowers) ), parentPairs )) ) : parentPairs; return map(snd, treeGrowth(nDigits, [])); }; // GENERIC FUNCTIONS ------------------------------------------------------ // enumFromTo :: Int -> Int -> Maybe Int -> [Int] const enumFromTo = (m, n, step) => { const d = (step || 1) * (n >= m ? 1 : -1); return Array.from({ length: Math.floor((n - m) / d) + 1 }, (_, i) => m + (i * d)); }; // concatMap :: (a -> [b]) -> [a] -> [b] const concatMap = (f, xs) => [].concat.apply([], xs.map(f)); // cons :: a -> [a] -> [a] const cons = (x, xs) => [x].concat(xs); // 2 or more arguments // curry :: Function -> Function const curry = (f, ...args) => { const go = xs => xs.length >= f.length ? (f.apply(null, xs)) : function () { return go(xs.concat([].slice.apply(arguments))); }; return go([].slice.call(args, 1)); }; // filter :: (a -> Bool) -> [a] -> [a] const filter = (f, xs) => xs.filter(f); // map :: (a -> b) -> [a] -> [b] const map = curry((f, xs) => xs.map(f)); // isNull :: [a] -> Bool const isNull = xs => (xs instanceof Array) ? xs.length < 1 : undefined; // length :: [a] -> Int const length = xs => xs.length; // pow :: Int -> Int -> Int const pow = Math.pow // take :: Int -> [a] -> [a] const take = (n, xs) => xs.slice(0, n); // show :: // (a -> String) f, Num n => // a -> maybe f -> maybe n -> String const show = JSON.stringify; // snd :: (a, b) -> b const snd = tpl => Array.isArray(tpl) ? tpl[1] : undefined; // TEST ------------------------------------------------------------------- // return length(concatMap(digitPowerSums, enumFromTo(0, 7))); return show( //digitPowerSums(3) concatMap(narcissiOfLength, enumFromTo(0, 7)) ); })(); ``` {{Out}} (Tested in Atom editor, using Script package) ```txt [0,1,2,3,4,5,6,7,8,9,153,370,371,407,1634,8208,9474,54748,92727,93084,548834,1741725,4210818,9800817,9926315] [Finished in 0.118s] ``` ## jq {{works with|jq|1.4}} A function for checking whether a given non-negative integer is narcissistic could be implemented in jq as follows: ```jq def is_narcissistic: def digits: tostring | explode[] | [.] | implode | tonumber; def pow(n): . as $x | reduce range(0;n) as $i (1; . * $x); (tostring | length) as $len | . == reduce digits as $d (0; . + ($d | pow($len)) ) end; ``` In the following, this definition is modified to avoid recomputing (d ^ i). This is accomplished introducing the array [i, [0^i, 1^i, ..., 9^i]]. To update this array for increasing values of i, the function powers(j) is defined as follows: ```jq # Input: [i, [0^i, 1^i, 2^i, ..., 9^i]] # Output: [j, [0^j, 1^j, 2^j, ..., 9^j]] # provided j is i or (i+1) def powers(j): if .[0] == j then . else .[0] += 1 | reduce range(0;10) as $k (.; .[1][$k] *= $k) end; ``` The function is_narcisstic can now be modified to use powers(j) as follows: ```jq # Input: [n, [i, [0^i, 1^i, 2^i,...]]] where i is the number of digits in n. def is_narcissistic: def digits: tostring | explode[] | [.] | implode | tonumber; .[1][1] as $powers | .[0] | if . < 0 then false else . == reduce digits as $d (0; . + $powers[$d] ) end; ``` '''The task''' ```jq # If your jq has "while", then feel free to omit the following definition: def while(cond; update): def _while: if cond then ., (update | _while) else empty end; _while; # The first k narcissistic numbers, beginning with 0: def narcissistic(k): # State: [n, is_narcissistic, count, [len, [0^len, 1^len, ...]]] # where len is the number of digits in n. [0, true, 1, [1, [range(0;10)]]] | while( .[2] <= k; .[3] as $powers | (.[0]+1) as $n | ($n | tostring | length) as $len | ($powers | powers($len)) as $powersprime | if [$n, $powersprime] | is_narcissistic then [$n, true, .[2] + 1, $powersprime] else [$n, false, .[2], $powersprime ] end ) | select(.[1]) | "\(.[2]): \(.[0])" ; narcissistic(25) ``` {{out}} ```sh jq -r -n -f Narcissitic_decimal_number.jq 1: 0 2: 1 3: 2 4: 3 5: 4 6: 5 7: 6 8: 7 9: 8 10: 9 11: 153 12: 370 13: 371 14: 407 15: 1634 16: 8208 17: 9474 18: 54748 19: 92727 20: 93084 21: 548834 22: 1741725 23: 4210818 24: 9800817 25: 9926315 ``` ## Julia This easy to implement brute force technique is plenty fast enough to find the first few Narcissistic decimal numbers. ```Julia using Printf # for Julia version 1.0+ function isnarcissist(n, b=10) -1 < n || return false d = digits(n, base=b) m = length(d) n == mapreduce((x)->x^m, +, d) end function findnarcissist(verbose=false) goal = 25 ncnt = 0 verbose && println("Finding the first ", goal, " Narcissistic numbers:") for i in 0:typemax(1) isnarcissist(i) || continue ncnt += 1 verbose && println(@sprintf " %2d %7d" ncnt i) ncnt < goal || break end end findnarcissist() @time findnarcissist(true) ``` {{out}} ```txt Finding the first 25 Narcissistic numbers: 1 0 2 1 3 2 4 3 5 4 6 5 7 6 8 7 9 8 10 9 11 153 12 370 13 371 14 407 15 1634 16 8208 17 9474 18 54748 19 92727 20 93084 21 548834 22 1741725 23 4210818 24 9800817 25 9926315 3.054463 seconds (19.90 M allocations: 1.466 GiB, 14.27% gc time) ``` ## Kotlin ```scala // version 1.1.0 fun isNarcissistic(n: Int): Boolean { if (n < 0) throw IllegalArgumentException("Argument must be non-negative") var nn = n val digits = mutableListOf() val powers = IntArray(10) { 1 } while (nn > 0) { digits.add(nn % 10) for (i in 1..9) powers[i] *= i // no need to calculate powers[0] nn /= 10 } val sum = digits.filter { it > 0 }.map { powers[it] }.sum() return n == sum } fun main(args: Array ) { println("The first 25 narcissistic (or Armstrong) numbers are:") var i = 0 var count = 0 do { if (isNarcissistic(i)) { print("$i ") count++ } i++ } while (count < 25) } ``` {{out}} ```txt The first 25 narcissistic (or Armstrong) numbers are: 0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315 ``` ## Lua This is a simple/naive/slow method but it still spits out the requisite 25 in less than a minute using LuaJIT on a 2.5 GHz machine. ```Lua function isNarc (n) local m, sum, digit = string.len(n), 0 for pos = 1, m do digit = tonumber(string.sub(n, pos, pos)) sum = sum + digit^m end return sum == n end local n, count = 0, 0 repeat if isNarc(n) then io.write(n .. " ") count = count + 1 end n = n + 1 until count == 25 ``` {{out}} ```txt 0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315 ``` ## Maple ```Maple Narc:=proc(i) local num,len,j,sums: sums:=0: num := parse~(StringTools:-Explode((convert(i,string)))): len:=numelems(num): for j from 1 to len do sums:=sums+(num[j]^(len)): end do; if sums = i then return i; else return NULL; end if; end proc: i:=0: NDN:=[]: while numelems(NDN)<25 do NDN:=[op(NDN),(Narc(i))]: i:=i+1: end do: NDN; ``` ## Mathematica ```Mathematica narc[1] = 0; narc[n_] := narc[n] = NestWhile[# + 1 &, narc[n - 1] + 1, Plus @@ (IntegerDigits[#]^IntegerLength[#]) != # &]; narc /@ Range[25] ``` {{out}} ```txt {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 153, 370, 371, 407, 1634, 8208, 9474, 54748, 92727, 93084, 548834, 1741725, 4210818, 9800817, 9926315} ``` ## MATLAB ```MATLAB function testNarcissism x = 0; c = 0; while c < 25 if isNarcissistic(x) fprintf('%d ', x) c = c+1; end x = x+1; end fprintf('\n') end function tf = isNarcissistic(n) dig = sprintf('%d', n) - '0'; tf = n == sum(dig.^length(dig)); end ``` {{out}} ```txt 0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315 ``` ## Oforth ```Oforth : isNarcissistic(n) | i m | n 0 while( n ) [ n 10 /mod ->n swap 1 + ] ->m 0 m loop: i [ swap m pow + ] == ; : genNarcissistic(n) | l | ListBuffer new dup ->l 0 while(l size n <>) [ dup isNarcissistic ifTrue: [ dup l add ] 1 + ] drop ; ``` {{out}} ```txt >genNarcissistic(25) . [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 153, 370, 371, 407, 1634, 8208, 9474, 54748, 92727, 93084, 548834, 1741725, 4210818, 9800817, 9926315] ok ``` ## PARI/GP Naive code, could be improved by splitting the digits in half and meeting in the middle. ```parigp isNarcissistic(n)=my(v=digits(n)); sum(i=1, #v, v[i]^#v)==n v=List();for(n=1,1e9,if(isNarcissistic(n),listput(v,n);if(#v>24, return(Vec(v))))) ``` {{out}} ```txt %1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 153, 370, 371, 407, 1634, 8208, 9474, 54748, 92727, 93084, 548834, 1741725, 4210818, 9800817, 9926315, 24678050] ``` ## Pascal {{works with|Free Pascal}} A recursive version starting at the highest digit and recurses to digit 0. Bad runtime. One more digit-> 10x runtime runtime ~ 10^(count of Digits). ```pascal program NdN; //Narcissistic decimal number const Base = 10; MaxDigits = 16; type tDigit = 0..Base-1; tcntDgt= 0..MaxDigits-1; var powDgt : array[tDigit] of NativeUint; PotdgtPos: array[tcntDgt] of NativeUint; UpperSum : array[tcntDgt] of NativeUint; tmpSum, tmpN, actPot : NativeUint; procedure InitPowDig; var i,j : NativeUint; Begin j := 1; For i := 0 to High(tDigit) do Begin powDgt[i] := i; PotdgtPos[i] := j; j := j*Base; end; actPot := 0; end; procedure NextPowDig; var i,j : NativeUint; Begin // Next power of digit = i ^ actPot,always 0 = 0 , 1 = 1 For i := 2 to High(tDigit) do powDgt[i] := powDgt[i]*i; // number of digits times 9 ^(max number of digits) j := powDgt[High(tDigit)]; For i := 0 to High(UpperSum) do UpperSum[i] := (i+1)*j; inc(actPot); end; procedure OutPutNdN(n:NativeUint); Begin write(n,' '); end; procedure NextDgtSum(dgtPos,i,sumPowDgt,n:NativeUint); begin //unable to reach sum IF (sumPowDgt+UpperSum[dgtPos]) < n then EXIT; repeat tmpN := n+PotdgtPos[dgtPos]*i; tmpSum := sumPowDgt+powDgt[i]; //unable to get smaller if tmpSum > tmpN then EXIT; IF tmpSum = tmpN then OutPutNdN(tmpSum); IF dgtPos>0 then NextDgtSum(dgtPos-1,0,tmpSum,tmpN); inc(i); until i >= Base; end; var i : NativeUint; Begin InitPowDig; For i := 1 to 9 do Begin write(' length ',actPot+1:2,': '); //start with 1 in front, else you got i-times 0 in front NextDgtSum(actPot,1,0,0); writeln; NextPowDig; end; end. ``` ;output: ```txt time ./NdN length 1: 1 2 3 4 5 6 7 8 9 length 2: length 3: 153 370 370 371 407 length 4: 1634 8208 9474 length 5: 54748 92727 93084 length 6: 548834 length 7: 1741725 4210818 9800817 9926315 length 8: 24678050 24678050 24678051 88593477 length 9: 146511208 472335975 534494836 912985153 real 0m1.000s ``` ## Perl Simple version using a naive predicate. About 15 seconds. ```perl sub is_narcissistic { my $n = shift; my($k,$sum) = (length($n),0); $sum += $_**$k for split(//,$n); $n == $sum; } my $i = 0; for (1..25) { $i++ while !is_narcissistic($i); say $i++; } ``` ## Perl 6 Here is a straightforward, naive implementation. It works but takes ages. ```perl6 sub is-narcissistic(Int $n) { $n == [+] $n.comb »**» $n.chars } for 0 .. * { if .&is-narcissistic { .say; last if ++state$ >= 25; } } ``` {{out}} ```txt 0 1 2 3 4 5 6 7 8 9 153 370 371 407 Ctrl-C ``` Here the program was interrupted but if you're patient enough you'll see all the 25 numbers. Here's a faster version that precalculates the values for base 1000 digits: ```perl6 sub kigits($n) { my int $i = $n; my int $b = 1000; gather while $i { take $i % $b; $i = $i div $b; } } for (1..*) -> $d { my @t = 0..9 X** $d; my @table = @t X+ @t X+ @t; sub is-narcissistic(\n) { n == [+] @table[kigits(n)] }; state $l = 2; FIRST say "1\t0"; say $l++, "\t", $_ if .&is-narcissistic for 10**($d-1) ..^ 10**$d; last if $l > 25 }; ``` {{out}} ```txt 1 0 2 1 3 2 4 3 5 4 6 5 7 6 8 7 9 8 10 9 11 153 12 370 13 371 14 407 15 1634 16 8208 17 9474 18 54748 19 92727 20 93084 21 548834 22 1741725 23 4210818 24 9800817 25 9926315 ``` ## Phix ```Phix function narcissistic(integer n) string d = sprintf("%d",n) integer l = length(d) integer sumn = 0 for i=1 to l do sumn += power(d[i]-'0',l) end for return sumn=n end function sequence s = {} integer n = 0 while length(s)<25 do if narcissistic(n) then s &= n end if n += 1 end while ?s ``` {{out}} ```txt {0,1,2,3,4,5,6,7,8,9,153,370,371,407,1634,8208,9474,54748,92727,93084,548834,1741725,4210818,9800817,9926315} ``` ## PicoLisp ```PicoLisp (let (C 25 N 0 L 1) (loop (when (= N (sum ** (mapcar format (chop N)) (need L L)) ) (println N) (dec 'C) ) (inc 'N) (setq L (length N)) (T (=0 C) 'done) ) ) (bye) ``` ## PL/I ### version 1 {{trans|REXX}} ```pli narn: Proc Options(main); Dcl (j,k,l,nn,n,sum) Dec Fixed(15)init(0); Dcl s Char(15) Var; Dcl p(15) Pic'9' Based(addr(s)); Dcl (ms,msa,ela) Dec Fixed(15); Dcl tim Char(12); n=30; ms=milliseconds(); Do j=0 By 1 Until(nn=n); s=dec2str(j); l=length(s); sum=left(s,1)**l; Do k=2 To l; sum=sum+substr(s,k,1)**l; If sum>j Then Leave; End; If sum=j Then Do nn=nn+1; msa=milliseconds(); ela=msa-ms; /*Put Skip Data(ms,msa,ela);*/ ms=msa; /*yyyymmddhhmissmis*/ tim=translate('ij:kl:mn.opq',datetime(),'abcdefghijklmnopq'); Put Edit(nn,' narcissistic:',j,ela,tim) (Skip,f(9),a,f(12),f(15),x(2),a(12)); End; End; dec2str: Proc(x) Returns(char(16) var); Dcl x Dec Fixed(15); Dcl ds Pic'(14)z9'; ds=x; Return(trim(ds)); End; milliseconds: Proc Returns(Dec Fixed(15)); Dcl c17 Char(17); dcl 1 * Def C17, 2 * char(8), 2 hh Pic'99', 2 mm Pic'99', 2 ss Pic'99', 2 ms Pic'999'; Dcl result Dec Fixed(15); c17=datetime(); result=(((hh*60+mm)*60)+ss)*1000+ms; /* Put Edit(translate('ij:kl:mn.opq',datetime(),'abcdefghijklmnopq'), result) (Skip,a(12),F(15)); */ Return(result); End End; ``` {{out}} ```txt 1 narcissistic: 0 0 16:10:17.586 2 narcissistic: 1 0 16:10:17.586 3 narcissistic: 2 0 16:10:17.586 4 narcissistic: 3 0 16:10:17.586 5 narcissistic: 4 0 16:10:17.586 6 narcissistic: 5 0 16:10:17.586 7 narcissistic: 6 0 16:10:17.586 8 narcissistic: 7 0 16:10:17.586 9 narcissistic: 8 0 16:10:17.586 10 narcissistic: 9 0 16:10:17.586 11 narcissistic: 153 0 16:10:17.586 12 narcissistic: 370 0 16:10:17.586 13 narcissistic: 371 0 16:10:17.586 14 narcissistic: 407 0 16:10:17.586 15 narcissistic: 1634 10 16:10:17.596 16 narcissistic: 8208 30 16:10:17.626 17 narcissistic: 9474 10 16:10:17.636 18 narcissistic: 54748 210 16:10:17.846 19 narcissistic: 92727 170 16:10:18.016 20 narcissistic: 93084 0 16:10:18.016 21 narcissistic: 548834 1630 16:10:19.646 22 narcissistic: 1741725 4633 16:10:24.279 23 narcissistic: 4210818 10515 16:10:34.794 24 narcissistic: 9800817 28578 16:11:03.372 25 narcissistic: 9926315 510 16:11:03.882 26 narcissistic: 24678050 73077 16:12:16.959 27 narcissistic: 24678051 0 16:12:16.959 28 narcissistic: 88593477 365838 16:18:22.797 29 narcissistic: 146511208 276228 16:22:59.025 30 narcissistic: 472335975 1682125 16:51:01.150 ``` ### version 2 Precompiled powers *process source xref attributes or(!); narn3: Proc Options(main); Dcl (i,j,k,l,nn,n,sum) Dec Fixed(15)init(0); Dcl s Char(15) Var; dcl t Char(15); Dcl p9(15) Pic'9' Based(addr(t)); Dcl (ms,msa,ela) Dec Fixed(15); Dcl tim Char(12); n=30; Dcl power(0:9,1:9) Dec Fixed(15); Do i=0 To 9; Do j=1 To 9; Power(i,j)=i**j; End; End; ms=milliseconds(); Do j=0 By 1 Until(nn=n); s=dec2str(j); t=s; l=length(s); sum=power(p9(1),l); Do k=2 To l; sum=sum+power(p9(k),l); If sum>j Then Leave; End; If sum=j Then Do; nn=nn+1; msa=milliseconds(); ela=msa-ms; ms=msa; /*yyyymmddhhmissmis*/ tim=translate('ij:kl:mn.opq',datetime(),'abcdefghijklmnopq'); Put Edit(nn,' narcissistic:',j,ela,tim) (Skip,f(9),a,f(12),f(15),x(2),a(12)); End; End; dec2str: Proc(x) Returns(char(15) var); Dcl x Dec Fixed(15); Dcl ds Pic'(14)z9'; ds=x; Return(trim(ds)); End; milliseconds: Proc Returns(Dec Fixed(15)); Dcl c17 Char(17); dcl 1 * Def C17, 2 * char(8), 2 hh Pic'99', 2 mm Pic'99', 2 ss Pic'99', 2 ms Pic'999'; Dcl result Dec Fixed(15); c17=datetime(); result=(((hh*60+mm)*60)+ss)*1000+ms; Return(result); End; End; ``` {{out}} ```txt 1 narcissistic: 0 0 00:41:43.632 2 narcissistic: 1 0 00:41:43.632 3 narcissistic: 2 0 00:41:43.632 4 narcissistic: 3 0 00:41:43.632 5 narcissistic: 4 0 00:41:43.632 6 narcissistic: 5 0 00:41:43.632 7 narcissistic: 6 0 00:41:43.632 8 narcissistic: 7 0 00:41:43.632 9 narcissistic: 8 0 00:41:43.632 10 narcissistic: 9 0 00:41:43.632 11 narcissistic: 153 0 00:41:43.632 12 narcissistic: 370 0 00:41:43.632 13 narcissistic: 371 0 00:41:43.632 14 narcissistic: 407 0 00:41:43.632 15 narcissistic: 1634 0 00:41:43.632 16 narcissistic: 8208 20 00:41:43.652 17 narcissistic: 9474 10 00:41:43.662 18 narcissistic: 54748 130 00:41:43.792 19 narcissistic: 92727 120 00:41:43.912 20 narcissistic: 93084 0 00:41:43.912 21 narcissistic: 548834 1310 00:41:45.222 22 narcissistic: 1741725 3642 00:41:48.864 23 narcissistic: 4210818 7488 00:41:56.352 24 narcissistic: 9800817 22789 00:42:19.141 25 narcissistic: 9926315 550 00:42:19.691 26 narcissistic: 24678050 45358 00:43:05.049 27 narcissistic: 24678051 0 00:43:05.049 28 narcissistic: 88593477 237960 00:47:03.009 29 narcissistic: 146511208 199768 00:50:22.777 30 narcissistic: 472335975 1221384 01:10:44.161 ``` ## PowerShell ```PowerShell function Test-Narcissistic ([int]$Number) { if ($Number -lt 0) {return $false} $total = 0 $digits = $Number.ToString().ToCharArray() foreach ($digit in $digits) { $total += [Math]::Pow([Char]::GetNumericValue($digit), $digits.Count) } $total -eq $Number } [int[]]$narcissisticNumbers = @() [int]$i = 0 while ($narcissisticNumbers.Count -lt 25) { if (Test-Narcissistic -Number $i) { $narcissisticNumbers += $i } $i++ } $narcissisticNumbers | Format-Wide {"{0,7}" -f $_} -Column 5 -Force ``` {{Out}} ```txt 0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315 ``` ## Python This solution pre-computes the powers once. ```python from __future__ import print_function from itertools import count, islice def narcissists(): for digits in count(0): digitpowers = [i**digits for i in range(10)] for n in range(int(10**(digits-1)), 10**digits): div, digitpsum = n, 0 while div: div, mod = divmod(div, 10) digitpsum += digitpowers[mod] if n == digitpsum: yield n for i, n in enumerate(islice(narcissists(), 25), 1): print(n, end=' ') if i % 5 == 0: print() print() ``` {{out}} ```txt 0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315 ``` ### Faster Version {{trans|D}} ```python try: import psyco psyco.full() except: pass class Narcissistics: def __init__(self, max_len): self.max_len = max_len self.power = [0] * 10 self.dsum = [0] * (max_len + 1) self.count = [0] * 10 self.len = 0 self.ord0 = ord('0') def check_perm(self, out = [0] * 10): for i in xrange(10): out[i] = 0 s = str(self.dsum[0]) for d in s: c = ord(d) - self.ord0 out[c] += 1 if out[c] > self.count[c]: return if len(s) == self.len: print self.dsum[0], def narc2(self, pos, d): if not pos: self.check_perm() return while True: self.dsum[pos - 1] = self.dsum[pos] + self.power[d] self.count[d] += 1 self.narc2(pos - 1, d) self.count[d] -= 1 if d == 0: break d -= 1 def show(self, n): self.len = n for i in xrange(len(self.power)): self.power[i] = i ** n self.dsum[n] = 0 print "length %d:" % n, self.narc2(n, 9) print def main(): narc = Narcissistics(14) for i in xrange(1, narc.max_len + 1): narc.show(i) main() ``` {{out}} ```txt length 1: 9 8 7 6 5 4 3 2 1 0 length 2: length 3: 407 371 370 153 length 4: 9474 8208 1634 length 5: 93084 92727 54748 length 6: 548834 length 7: 9926315 9800817 4210818 1741725 length 8: 88593477 24678051 24678050 length 9: 912985153 534494836 472335975 146511208 length 10: 4679307774 length 11: 94204591914 82693916578 49388550606 44708635679 42678290603 40028394225 32164049651 32164049650 length 12: length 13: length 14: 28116440335967 ``` ## Racket ```racket ;; OEIS: A005188 defines these as positive numbers, so I will follow that definition in the function ;; definitions. ;; ;; 0: assuming it is represented as the single digit 0 (and not an empty string, which is not the ;; usual convention for 0 in decimal), is not: sum(0^0), which is 1. 0^0 is a strange one, ;; wolfram alpha calls returns 0^0 as indeterminate -- so I will defer to the brains behind OEIS ;; on the definition here, rather than copy what I'm seeing in some of the results here #lang racket ;; Included for the serious efficientcy gains we get from fxvectors vs. general vectors. ;; ;; We also use fx+/fx- etc. As it stands, they do a check for fixnumness, for safety. ;; We can link them in as "unsafe" operations (see the documentation on racket/fixnum); ;; but we get a result from this program quickly enough for my tastes. (require racket/fixnum) ; uses a precalculated (fx)vector of powers -- caller provided, please. (define (sub-narcissitic? N powered-digits) (let loop ((n N) (target N)) (cond [(fx> 0 target) #f] [(fx= 0 target) (fx= 0 n)] [(fx= 0 n) #f] [else (loop (fxquotient n 10) (fx- target (fxvector-ref powered-digits (fxremainder n 10))))]))) ; Can be used as standalone, since it doesn't require caller to care about things like order of ; magnitude etc. However, it *is* slow, since it regenerates the powered-digits vector every time. (define (narcissitic? n) ; n is +ve (define oom+1 (fx+ 1 (order-of-magnitude n))) (define powered-digits (for/fxvector ((i 10)) (expt i oom+1))) (sub-narcissitic? n powered-digits)) ;; next m primes > z (define (next-narcissitics z m) ; naming convention following math/number-theory's next-primes (let-values ([(i l) (for*/fold ((i (fx+ 1 z)) (l empty)) ((oom (in-naturals)) (dgts^oom (in-value (for/fxvector ((i 10)) (expt i (add1 oom))))) (n (in-range (expt 10 oom) (expt 10 (add1 oom)))) #:when (sub-narcissitic? n dgts^oom) ; everyone else uses ^C to break... ; that's a bit of a manual process, don't you think? #:final (= (fx+ 1 (length l)) m)) (values (+ i 1) (append l (list n))))]) l)) ; we only want the list (module+ main (next-narcissitics 0 25) ; here's another list... depending on whether you believe sloane or wolfram :-) (cons 0 (next-narcissitics 0 25))) (module+ test (require rackunit) ; example given at head of task (check-true (narcissitic? 153)) ; rip off the first 12 (and 0, since Armstrong numbers seem to be postivie) from ; http://oeis.org/A005188 for testing (check-equal? (for/list ((i (in-range 12)) (n (sequence-filter narcissitic? (in-naturals 1)))) n) '(1 2 3 4 5 6 7 8 9 153 370 371)) (check-equal? (next-narcissitics 0 12) '(1 2 3 4 5 6 7 8 9 153 370 371))) ``` {{out}} ```txt (1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315 24678050) (0 1 2 ... 9926315) ``` ### Faster Version This version uses lists of digits, rather than numbers themselves. ```racket #lang racket (define (non-decrementing-digital-sequences L) (define (inr d l) (cond [(<= l 0) '(())] [(= d 9) (list (make-list l d))] [else (append (map (curry cons d) (inr d (- l 1))) (inr (+ d 1) l))])) (inr 0 L)) (define (integer->digits-list n) (let inr ((n n) (l null)) (if (zero? n) l (inr (quotient n 10) (cons (modulo n 10) l))))) (define (narcissitic-numbers-of-length L) (define tail-digits (non-decrementing-digital-sequences (sub1 L))) (define powers-v (for/fxvector #:length 10 ((i 10)) (expt i L))) (define (powers-sum dgts) (for/sum ((d (in-list dgts))) (fxvector-ref powers-v d))) (for*/list ((dgt1 (in-range 1 10)) (dgt... (in-list tail-digits)) (sum-dgt^l (in-value (powers-sum (cons dgt1 dgt...)))) (dgts-sum (in-value (integer->digits-list sum-dgt^l))) #:when (= (car dgts-sum) dgt1) ; only now is it worth sorting the digits #:when (equal? (sort (cdr dgts-sum) <) dgt...)) sum-dgt^l)) (define (narcissitic-numbers-of-length<= L) (cons 0 ; special! (apply append (for/list ((l (in-range 1 (+ L 1)))) (narcissitic-numbers-of-length l))))) (module+ main (define all-narcissitics<10000000 (narcissitic-numbers-of-length<= 7)) ; conveniently, this *is* the list of 25... but I'll be a bit pedantic anyway (take all-narcissitics<10000000 25)) (module+ test (require rackunit) (check-equal? (non-decrementing-digital-sequences 1) '((0) (1) (2) (3) (4) (5) (6) (7) (8) (9))) (check-equal? (non-decrementing-digital-sequences 2) '((0 0) (0 1) (0 2) (0 3) (0 4) (0 5) (0 6) (0 7) (0 8) (0 9) (1 1) (1 2) (1 3) (1 4) (1 5) (1 6) (1 7) (1 8) (1 9) (2 2) (2 3) (2 4) (2 5) (2 6) (2 7) (2 8) (2 9) (3 3) (3 4) (3 5) (3 6) (3 7) (3 8) (3 9) (4 4) (4 5) (4 6) (4 7) (4 8) (4 9) (5 5) (5 6) (5 7) (5 8) (5 9) (6 6) (6 7) (6 8) (6 9) (7 7) (7 8) (7 9) (8 8) (8 9) (9 9))) (check-equal? (integer->digits-list 0) null) (check-equal? (integer->digits-list 7) '(7)) (check-equal? (integer->digits-list 10) '(1 0)) (check-equal? (narcissitic-numbers-of-length 1) '(1 2 3 4 5 6 7 8 9)) (check-equal? (narcissitic-numbers-of-length 2) '()) (check-equal? (narcissitic-numbers-of-length 3) '(153 370 371 407)) (check-equal? (narcissitic-numbers-of-length<= 1) '(0 1 2 3 4 5 6 7 8 9)) (check-equal? (narcissitic-numbers-of-length<= 3) '(0 1 2 3 4 5 6 7 8 9 153 370 371 407))) ``` {{out}} ```txt '(0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 93084 92727 548834 1741725 4210818 9800817 9926315) ``` ## REXX ### idiomatic ```rexx /*REXX program generates and displays a number of narcissistic (Armstrong) numbers. */ numeric digits 39 /*be able to handle largest Armstrong #*/ parse arg N . /*obtain optional argument from the CL.*/ if N=='' | N=="," then N=25 /*Not specified? Then use the default.*/ N=min(N, 89) /*there are only 89 narcissistic #s. */ #=0 /*number of narcissistic numbers so far*/ do j=0 until #==N; L=length(j) /*get length of the J decimal number.*/ $=left(j, 1) **L /*1st digit in J raised to the L pow.*/ do k=2 for L-1 until $>j /*perform for each decimal digit in J.*/ $=$ + substr(j, k, 1) ** L /*add digit raised to power to the sum.*/ end /*k*/ /* [↑] calculate the rest of the sum. */ if $\==j then iterate /*does the sum equal to J? No, skip it*/ #=# + 1 /*bump count of narcissistic numbers. */ say right(#, 9) ' narcissistic:' j /*display index and narcissistic number*/ end /*j*/ /*stick a fork in it, we're all done. */ ``` {{out|output|text= when using the default input:}} ```txt 1 narcissistic: 0 2 narcissistic: 1 3 narcissistic: 2 4 narcissistic: 3 5 narcissistic: 4 6 narcissistic: 5 7 narcissistic: 6 8 narcissistic: 7 9 narcissistic: 8 10 narcissistic: 9 11 narcissistic: 153 12 narcissistic: 370 13 narcissistic: 371 14 narcissistic: 407 15 narcissistic: 1634 16 narcissistic: 8208 17 narcissistic: 9474 18 narcissistic: 54748 19 narcissistic: 92727 20 narcissistic: 93084 21 narcissistic: 548834 22 narcissistic: 1741725 23 narcissistic: 4210818 24 narcissistic: 9800817 25 narcissistic: 9926315 ``` ### optimized This REXX version is optimized to pre-compute all the ten (single) digits raised to all possible powers (there are only 39 possible widths/powers of narcissistic numbers). It is about '''77%''' faster then 1st REXX version. ```rexx /*REXX program generates and displays a number of narcissistic (Armstrong) numbers. */ numeric digits 39 /*be able to handle largest Armstrong #*/ parse arg N . /*obtain optional argument from the CL.*/ if N=='' | N=="," then N=25 /*Not specified? Then use the default.*/ N=min(N, 89) /*there are only 89 narcissistic #s. */ do p=1 for 39 /*generate tables: digits ^ P power. */ do i=0 for 10; @.p.i= i**p /*build table of ten digits ^ P power. */ end /*i*/ end /*w*/ /* [↑] table is a fixed (limited) size*/ #=0 /*number of narcissistic numbers so far*/ do j=0 until #==N; L=length(j) /*get length of the J decimal number.*/ _=left(j, 1) /*select the first decimal digit to sum*/ $=@.L._ /*sum of the J dec. digits ^ L (so far)*/ do k=2 for L-1 until $>j /*perform for each decimal digit in J.*/ _=substr(j, k, 1) /*select the next decimal digit to sum.*/ $=$ + @.L._ /*add dec. digit raised to power to sum*/ end /*k*/ /* [↑] calculate the rest of the sum. */ if $\==j then iterate /*does the sum equal to J? No, skip it*/ #=# + 1 /*bump count of narcissistic numbers. */ say right(#, 9) ' narcissistic:' j /*display index and narcissistic number*/ end /*j*/ /*stick a fork in it, we're all done. */ ``` {{out|output|text= is identical to the 1st REXX version.}} ===optimized, unrolled=== This REXX version is further optimized by unrolling part of the '''do''' loop that sums the decimal digits. The unrolling also necessitated the special handling of one─ and two─digit narcissistic numbers. It is about '''44%''' faster then 2nd REXX version, and it is about '''154%''' faster then 1st REXX version. ```rexx /*REXX program generates and displays a number of narcissistic (Armstrong) numbers. */ numeric digits 39 /*be able to handle largest Armstrong #*/ parse arg N . /*obtain optional argument from the CL.*/ if N=='' | N=="," then N=25 /*Not specified? Then use the default.*/ N=min(N, 89) /*there are only 89 narcissistic #s. */ @.=0 /*set default for the @ stemmed array. */ #=0 /*number of narcissistic numbers so far*/ do p=0 for 39+1; if p<10 then call tell p /*display the 1st 1─digit dec. numbers.*/ do i=1 for 9; @.p.i= i**p /*build table of ten digits ^ P power. */ end /*i*/ end /*p*/ /* [↑] table is a fixed (limited) size*/ /* [↓] skip the 2─digit dec. numbers. */ do j=100; L=length(j) /*get length of the J decimal number.*/ parse var j _1 2 _2 3 m '' -1 _R /*get 1st, 2nd, middle, last dec. digit*/ $=@.L._1 + @.L._2 + @.L._R /*sum of the J decimal digs^L (so far).*/ do k=3 for L-3 until $>j /*perform for other decimal digits in J*/ parse var m _ +1 m /*get next dec. dig in J, start at 3rd.*/ $=$ + @.L._ /*add dec. digit raised to pow to sum. */ end /*k*/ /* [↑] calculate the rest of the sum. */ if $==j then do; call tell j /*does the sum equal to J? Show the #*/ if #==n then leave /*does the sum equal to J? Show the #*/ end end /*j*/ /* [↑] the J loop list starts at 100*/ exit /*stick a fork in it, we're all done. */ /*──────────────────────────────────────────────────────────────────────────────────────*/ tell: #=# + 1 /*bump the counter for narcissistic #s.*/ say right(#,9) ' narcissistic:' arg(1) /*display index and narcissistic number*/ if #==n & n<11 then exit /*finished showing of narcissistic #'s?*/ return /*return to invoker & keep on truckin'.*/ ``` {{out|output|text= is identical to the 1st REXX version.}} ===optimized, 3-digit chunks=== This REXX version is further optimized by pre-computing the narcissistic sums of all two-digit and three-digit numbers (and also including those with leading zeros). It is about '''65%''' faster then 3rd REXX version, and it is about '''136%''' faster then 2nd REXX version, and it is about '''317%''' faster then 1st REXX version. ```rexx /*REXX program generates and displays a number of narcissistic (Armstrong) numbers. */ numeric digits 39 /*be able to handle largest Armstrong #*/ parse arg N . /*obtain optional argument from the CL.*/ if N=='' | N=="," then N=25 /*Not specified? Then use the default.*/ N=min(N, 89) /*there are only 89 narcissistic #s. */ @.=0 /*set default for the @ stemmed array. */ #=0 /*number of narcissistic numbers so far*/ do p=0 for 39+1; if p<10 then call tell p /*display the 1st 1─digit dec. numbers.*/ do i=1 for 9; @.p.i= i**p /*build table of ten digits ^ P power. */ zzj= '00'j; @.p.zzj= @.p.j /*assign value for a 3-dig number (LZ),*/ end /*i*/ do j=10 to 99; parse var j t 2 u /*obtain 2 decimal digits of J: T U */ @.p.j = @.p.t + @.p.u /*assign value for a 2─dig number. */ zj= '0'j; @.p.zj = @.p.j /* " " " " 3─dig " (LZ),*/ end /*j*/ /* [↑] T≡ tens digit; U≡ units digit.*/ do k=100 to 999; parse var k h 2 t 3 u /*obtain 3 decimal digits of J: H T U */ @.p.k= @.p.h + @.p.t + @.p.u /*assign value for a three-digit number*/ end /*k*/ /* [↑] H≡ hundreds digit; T≡ tens ···*/ end /*p*/ /* [↑] table is a fixed (limited) size*/ /* [↓] skip the 2─digit dec. numbers. */ do j=100; L=length(j) /*get length of the J decimal number.*/ parse var j _ +3 m /*get 1st three decimal digits of J. */ $=@.L._ /*sum of the J decimal digs^L (so far).*/ do while m\=='' /*do the rest of the dec. digs in J. */ parse var m _ +3 m /*get the next 3 decimal digits in M. */ $=$ + @.L._ /*add dec. digit raised to pow to sum. */ end /*while*/ /* [↑] calculate the rest of the sum. */ if $==j then do; call tell j /*does the sum equal to J? Show the #*/ if #==n then leave /*does the sum equal to J? Show the #*/ end end /*j*/ /* [↑] the J loop list starts at 100*/ exit /*stick a fork in it, we're all done. */ /*──────────────────────────────────────────────────────────────────────────────────────*/ tell: #=# + 1 /*bump the counter for narcissistic #s.*/ say right(#,9) ' narcissistic:' arg(1) /*display index and narcissistic number*/ if #==n & n<11 then exit /*finished showing of narcissistic #'s?*/ return /*return to invoker & keep on truckin'.*/ ``` {{out|output|text= is identical to the 1st REXX version.}} Further optimization could be utilized by increasing the chunk size to four or five decimal digits, but with an accompanying increase in the size of the pre-computed values. ## Ring ```ring n = 0 count = 0 size = 15 while count != size m = isNarc(n) if m=1 see "" + n + " is narcisstic" + nl count = count + 1 ok n = n + 1 end func isNarc n m = len(string(n)) sum = 0 digit = 0 for pos = 1 to m digit = number(substr(string(n), pos, 1)) sum = sum + pow(digit,m) next nr = (sum = n) return nr ``` ## Ruby ```ruby class Integer def narcissistic? return false if negative? digs = self.digits m = digs.size digs.map{|d| d**m}.sum == self end end puts 0.step.lazy.select(&:narcissistic?).first(25) ``` {{out}} ```txt 0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315 ``` ## Scala {{works with|Scala|2.9.x}} ```Scala object NDN extends App { val narc: Int => Int = n => (n.toString map (_.asDigit) map (math.pow(_, n.toString.size)) sum) toInt val isNarc: Int => Boolean = i => i == narc(i) println((Iterator from 0 filter isNarc take 25 toList) mkString(" ")) } ``` Output: ```txt 0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315 ``` ## Sidef ```ruby func is_narcissistic(n) { n.digits »**» n.len -> sum == n } var count = 0 for i in ^Inf { if (is_narcissistic(i)) { say "#{++count}\t#{i}" break if (count == 25) } } ``` {{out}} ```txt 1 0 2 1 3 2 4 3 5 4 6 5 7 6 8 7 9 8 10 9 11 153 12 370 13 371 14 407 15 1634 16 8208 17 9474 18 54748 19 92727 20 93084 21 548834 22 1741725 23 4210818 24 9800817 25 9926315 ``` ## Tcl ```tcl proc isNarcissistic {n} { set m [string length $n] for {set t 0; set N $n} {$N} {set N [expr {$N / 10}]} { incr t [expr {($N%10) ** $m}] } return [expr {$n == $t}] } proc firstNarcissists {target} { for {set n 0; set count 0} {$count < $target} {incr n} { if {[isNarcissistic $n]} { incr count lappend narcissists $n } } return $narcissists } puts [join [firstNarcissists 25] ","] ``` {{out}} ```txt 0,1,2,3,4,5,6,7,8,9,153,370,371,407,1634,8208,9474,54748,92727,93084,548834,1741725,4210818,9800817,9926315 ``` ## UNIX Shell {{works with|ksh93}} ```bash function narcissistic { integer n=$1 len=${#n} sum=0 i for ((i=0; i n results of f(i).toBool()==True). ```zkl ns:=[0..].filter.fp1(isNarcissistic); ns(15).println(); ns(5).println(); ns(5).println(); ``` {{out}} ```txt L(0,1,2,3,4,5,6,7,8,9,153,370,371,407,1634) L(8208,9474,54748,92727,93084) L(548834,1741725,4210818,9800817,9926315) ``` ## ZX Spectrum Basic Array index starts at 1. Only 1 character long variable names are allowed for For-Next loops. 8 Digits or higher numbers are displayed as floating point numbers. Needs about 2 hours (3.5Mhz) ```zxbasic 1 DIM K(10): DIM M(10) 2 FOR Y=0 TO 9: LET M(Y+1)=Y: NEXT Y 3 FOR N=1 TO 7 4 FOR J=N TO 0 STEP -1 5 FOR I=N-J TO 0 STEP -1 6 FOR H=N-J-I TO 0 STEP -1 7 FOR G=N-J-I-H TO 0 STEP -1 8 FOR F=N-J-I-H-G TO 0 STEP -1 9 FOR E=N-J-I-H-G-F TO 0 STEP -1 10 FOR D=N-J-I-H-G-F-E TO 0 STEP -1 11 FOR C=N-J-I-H-G-F-E-D TO 0 STEP -1 12 FOR B=N-J-I-H-G-F-E-D-C TO 0 STEP -1 13 LET A=N-J-I-H-G-F-E-D-C-B 14 LET X=B+C*M(3)+D*M(4)+E*M(5)+F*M(6)+G*M(7)+H*M(8)+I*M(9)+J*M(10) 15 LET S$=STR$ (X) 16 IF LEN (S$) N THEN GO TO 33 18 FOR Y=1 TO 10: LET K(Y)=0: NEXT Y 19 FOR Y=1 TO N 20 LET Z= CODE (S$(Y))-47 21 LET K(Z)=K(Z)+1 22 NEXT Y 23 IF A<>K(1) THEN GO TO 33 24 IF B<>K(2) THEN GO TO 33 25 IF C<>K(3) THEN GO TO 33 26 IF D<>K(4) THEN GO TO 33 27 IF E<>K(5) THEN GO TO 33 28 IF F<>K(6) THEN GO TO 33 29 IF G<>K(7) THEN GO TO 33 30 IF H<>K(8) THEN GO TO 33 31 IF I<>K(9) THEN GO TO 33 32 IF J=K(10) THEN PRINT X, 33 NEXT B: NEXT C: NEXT D: NEXT E: NEXT F: NEXT G: NEXT H: NEXT I: NEXT J 34 FOR Y=2 TO 9 35 LET M(Y+1)=M(Y+1)*Y 36 NEXT Y 37 NEXT N 38 PRINT 39 PRINT "DONE" ``` {{out}} ```txt 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 407 371 370 153 9474 8208 1634 93084 92727 54748 548834 9926315 9800817 4210818 1741725 ```