Task
Show the first 30 positive integers which are squares but not cubes of such integers.
Optionally, show also the first 3 positive integers which are both squares and cubes - and mark them as such.
ALGOL 68
Avoids computing cube roots.
BEGIN
# list the first 30 numbers that are squares but not cubes and also #
# show the numbers that are both squares and cubes #
INT count := 0;
INT c := 1;
INT c3 := 1;
FOR s WHILE count < 30 DO
INT sq = s * s;
WHILE c3 < sq DO
c +:= 1;
c3 := c * c * c
OD;
print( ( whole( sq, -5 ) ) );
IF c3 = sq THEN
# the square is also a cube #
print( ( " is also the cube of ", whole( c, -5 ) ) )
ELSE
# square only #
count +:= 1
FI;
print( ( newline ) )
OD
END
1 is also the cube of 1
4
9
16
25
36
49
64 is also the cube of 4
81
100
121
144
169
196
225
256
289
324
361
400
441
484
529
576
625
676
729 is also the cube of 9
784
841
900
961
1024
1089
AppleScript
on run
script listing
on |λ|(x)
set sqr to x * x
set strSquare to sqr as text
if isCube(sqr) then
strSquare & " (also cube)"
else
strSquare
end if
end |λ|
end script
unlines(map(listing, ¬
enumFromTo(1, 33)))
end run
-- isCube :: Int -> Bool
on isCube(x)
x = (round (x ^ (1 / 3))) ^ 3
end isCube
-- GENERIC FUNCTIONS -------------------------------------------------
-- enumFromTo :: Int -> Int -> [Int]
on enumFromTo(m, n)
if m ≤ n then
set lst to {}
repeat with i from m to n
set end of lst to i
end repeat
return lst
else
return {}
end if
end enumFromTo
-- 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 :: First-class m => (a -> b) -> m (a -> b)
on mReturn(f)
if class of f is script then
f
else
script
property |λ| : f
end script
end if
end mReturn
-- unlines :: [String] -> String
on unlines(xs)
set {dlm, my text item delimiters} to ¬
{my text item delimiters, linefeed}
set str to xs as text
set my text item delimiters to dlm
str
end unlines
1 (also cube)
4
9
16
25
36
49
64 (also cube)
81
100
121
144
169
196
225
256
289
324
361
400
441
484
529
576
625
676
729 (also cube)
784
841
900
961
1024
1089
AWK
# syntax: GAWK -f SQUARE_BUT_NOT_CUBE.AWK
BEGIN {
while (n < 30) {
sqpow = ++square ^ 2
if (is_cube(sqpow) == 0) {
n++
printf("%4d\n",sqpow)
}
else {
printf("%4d is square and cube\n",sqpow)
}
}
exit(0)
}
function is_cube(x, i) {
for (i=1; i<=x; i++) {
if (i ^ 3 == x) {
return(1)
}
}
return(0)
}
1 is square and cube
4
9
16
25
36
49
64 is square and cube
81
100
121
144
169
196
225
256
289
324
361
400
441
484
529
576
625
676
729 is square and cube
784
841
900
961
1024
1089
C
#include <stdio.h>
#include <math.h>
int main() {
int n = 1, count = 0, sq, cr;
for ( ; count < 30; ++n) {
sq = n * n;
cr = (int)cbrt((double)sq);
if (cr * cr * cr != sq) {
count++;
printf("%d\n", sq);
}
else {
printf("%d is square and cube\n", sq);
}
}
return 0;
}
Same as Ring example.
C++
#include <iostream>
#include <cmath>
int main() {
int n = 1;
int count = 0;
int sq;
int cr;
for (; count < 30; ++n) {
sq = n * n;
cr = cbrt(sq);
if (cr * cr * cr != sq) {
count++;
std::cout << sq << '\n';
} else {
std::cout << sq << " is square and cube\n";
}
}
return 0;
}
1 is square and cube
4
9
16
25
36
49
64 is square and cube
81
100
121
144
169
196
225
256
289
324
361
400
441
484
529
576
625
676
729 is square and cube
784
841
900
961
1024
1089
C#
using System;
using System.Collections.Generic;
using static System.Console;
using static System.Linq.Enumerable;
public static class SquareButNotCube
{
public static void Main() {
var squares = from i in Integers() select i * i;
var cubes = from i in Integers() select i * i * i;
foreach (var x in Merge().Take(33)) {
WriteLine(x.isCube ? x.n + " (also cube)" : x.n + "");
}
IEnumerable<int> Integers() {
for (int i = 1; ;i++) yield return i;
}
IEnumerable<(int n, bool isCube)> Merge() {
using (var s = squares.GetEnumerator())
using (var c = cubes.GetEnumerator()) {
s.MoveNext();
c.MoveNext();
while (true) {
if (s.Current < c.Current) {
yield return (s.Current, false);
s.MoveNext();
} else if (s.Current == c.Current) {
yield return (s.Current, true);
s.MoveNext();
c.MoveNext();
} else {
c.MoveNext();
}
}
}
}
}
}
1 (also cube)
4
9
16
25
36
49
64 (also cube)
81
100
121
144
169
196
225
256
289
324
361
400
441
484
529
576
625
676
729 (also cube)
784
841
900
961
1024
1089
```
## D
```d
import std.algorithm;
import std.range;
import std.stdio;
auto squareGen() {
struct Gen {
private int add = 3;
private int curr = 1;
bool empty() {
return curr < 0;
}
auto front() {
return curr;
}
void popFront() {
curr += add;
add += 2;
}
}
return Gen();
}
auto cubeGen() {
struct Gen {
private int add1 = 7;
private int add2 = 12;
private int curr = 1;
bool empty() {
return curr < 0;
}
auto front() {
return curr;
}
void popFront() {
curr += add1;
add1 += add2;
add2 += 6;
}
}
return Gen();
}
auto merge() {
struct Gen {
private auto sg = squareGen();
private auto cg = cubeGen();
bool empty() {
return sg.empty || cg.empty;
}
auto front() {
import std.typecons;
if (sg.front == cg.front) {
return tuple!("num", "isCube")(sg.front, true);
} else {
return tuple!("num", "isCube")(sg.front, false);
}
}
void popFront() {
while (true) {
if (sg.front < cg.front) {
sg.popFront();
return;
} else if (sg.front == cg.front) {
sg.popFront();
cg.popFront();
return;
} else {
cg.popFront();
}
}
}
}
return Gen();
}
void main() {
foreach (p; merge.take(33)) {
if (p.isCube) {
writeln(p.num, " (also cube)");
} else {
writeln(p.num);
}
}
}
```
```txt
1 (also cube)
4
9
16
25
36
49
64 (also cube)
81
100
121
144
169
196
225
256
289
324
361
400
441
484
529
576
625
676
729 (also cube)
784
841
900
961
1024
1089
```
=={{header|F_Sharp|F#}}==
```fsharp
let rec fN n g φ=if φ<31 then match compare(n*n)(g*g*g) with | -1->printfn "%d"(n*n);fN(n+1) g (φ+1)
| 0->printfn "%d cube and square"(n*n);fN(n+1)(g+1)φ
| 1->fN n (g+1) φ
fN 1 1 1
```
```txt
1 cube and square
4
9
16
25
36
49
64 cube and square
81
100
121
144
169
196
225
256
289
324
361
400
441
484
529
576
625
676
729 cube and square
784
841
900
961
1024
1089
```
## Factor
```factor
USING: combinators interpolate io kernel prettyprint math
math.functions math.order pair-rocket ;
IN: rosetta-code.square-but-not-cube
: fn ( s c n -- s' c' n' )
dup 31 < [
2over [ sq ] [ 3 ^ ] bi* <=> {
+lt+ => [ [ dup sq . 1 + ] 2dip 1 + fn ]
+eq+ => [ [ dup sq [I ${} cube and squareI] nl 1 + ] [ 1 + ] [ ] tri* fn ]
+gt+ => [ [ 1 + ] dip fn ]
} case
] when ;
1 1 1 fn 3drop
```
```txt
1 cube and square
4
9
16
25
36
49
64 cube and square
81
100
121
144
169
196
225
256
289
324
361
400
441
484
529
576
625
676
729 cube and square
784
841
900
961
1024
1089
```
## Go
```go
package main
import (
"fmt"
"math"
)
func main() {
for n, count := 1, 0; count < 30; n++ {
sq := n * n
cr := int(math.Cbrt(float64(sq)))
if cr*cr*cr != sq {
count++
fmt.Println(sq)
} else {
fmt.Println(sq, "is square and cube")
}
}
}
```
```txt
1 is square and cube
4
9
16
25
36
49
64 is square and cube
81
100
121
144
169
196
225
256
289
324
361
400
441
484
529
576
625
676
729 is square and cube
784
841
900
961
1024
1089
```
## Haskell
```haskell
import Data.List (partition, sortBy)
import Control.Monad (join)
import Data.Ord (comparing)
isCube :: Int -> Bool
isCube n = n == round (fromIntegral n ** (1 / 3)) ^ 3
both, only :: [Int]
(both, only) = partition isCube $ join (*) <$> [1 ..]
-- TEST -----------------------------------------------------------
main :: IO ()
main =
(putStrLn . unlines) $
uncurry ((++) . show) <$>
sortBy
(comparing fst)
((flip (,) " (also cube)" <$> take 3 both) ++ (flip (,) "" <$> take 30 only))
```
Or simply
```haskell
import Control.Monad (join)
cubeRoot :: Int -> Int
cubeRoot = round . (** (1 / 3)) . fromIntegral
isCube :: Int -> Bool
isCube = (==) <*> ((^ 3) . cubeRoot)
-- TEST ---------------------------------------------
main :: IO ()
main =
(putStrLn . unlines) $
(\x ->
show x ++
if isCube x
then concat [" (also cube of ", show (cubeRoot x), ")"]
else []) <$>
take 33 (join (*) <$> [1 ..])
```
Or, if we prefer a finite series to an infinite one
```haskell
isCube :: Int -> Bool
isCube = (==) <*> ((^ 3) . round . (** (1 / 3)) . fromIntegral)
squares :: Int -> Int -> [Int]
squares m n = (>>= id) (*) <$> [m .. n]
-- TEST ---------------------------------------------------
main :: IO ()
main = (putStrLn . unlines) $ (++) . show <*> label <$> squares 1 33
label :: Int -> String
label n
| isCube n = " (also cube)"
| otherwise = ""
```
```txt
1 (also cube)
4
9
16
25
36
49
64 (also cube)
81
100
121
144
169
196
225
256
289
324
361
400
441
484
529
576
625
676
729 (also cube)
784
841
900
961
1024
1089
```
=={{header|IS-BASIC}}==
100 PROGRAM "Square.bas"
110 LET SQNOTCB,SQANDCB,SQNUM,CBNUM,CBN,SQN,D1=0:LET SQD,D2=1
120 DO
130 LET SQN=SQN+1:LET SQNUM=SQNUM+SQD:LET SQD=SQD+2
140 IF SQNUM>CBNUM THEN
150 LET CBN=CBN+1:LET CBNUM=CBNUM+D2
160 LET D1=D1+6:LET D2=D2+D1
170 END IF
180 IF SQNUM<>CBNUM THEN
190 PRINT SQNUM:LET SQNOTCB=SQNOTCB+1
200 ELSE
210 PRINT SQNUM,SQN;"*";SQN;"=";CBN;"*";CBN;"*";CBN
220 LET SQANDCB=SQANDCB+1
230 END IF
240 LOOP UNTIL SQNOTCB>=30
250 PRINT SQANDCB;"where numbers are square and cube."
```
## J
'''Solution:'''
```j
isSqrNotCubeofInt=: (*. -.)/@(= <.)@(2 3 %:/ ])
getN_Indicies=: adverb def '[ ({. I.) [ (] , [: u (i.200) + #@])^:(> +/)^:_ u@]'
```
'''Example Use:'''
```j
I. isSqrNotCubeofInt i.1090 NB. If we know the upper limit required to get first 30
4 9 16 25 36 49 81 100 121 144 169 196 225 256 289 324 361 400 441 484 529 576 625 676 784 841 900 961 1024 1089
30 isSqrNotCubeofInt getN_Indicies 0 NB. otherwise iteratively build list until first 30 found
4 9 16 25 36 49 81 100 121 144 169 196 225 256 289 324 361 400 441 484 529 576 625 676 784 841 900 961 1024 1089
```
'''Alternative Solution:'''
Breaking up the solution above into smaller chunks with comments...
```j
isInt=: = <. NB. are numbers integers?
sqrcube=: 2 3 %:/ ] NB. table of 2nd and 3rd roots of y
isSqrNotCubeofInt=: (*. -.)/@isInt@sqrcube NB. is y the square but not cube of an integer?
getIdx=: {. I. NB. get indicies of first x ones in boolean y
process_more=: adverb def '] , [: u (i.200) + #@]' NB. process the next 200 indicies with u and append to y
notEnough=: > +/ NB. is left arg greater than sum of right arg
while=: conjunction def 'u^:v^:_' NB. repeat u while v is true
process_until_enough=: adverb def 'u process_more while notEnough u'
```
'''Example Use:'''
```j
30 ([ getIdx isSqrNotCubeofInt process_until_enough) 0
4 9 16 25 36 49 81 100 121 144 169 196 225 256 289 324 361 400 441 484 529 576 625 676 784 841
900 961 1024 1089
```
## Java
```java
public class SquaresCubes {
public static boolean isPerfectCube(long n) {
long c = (long)Math.cbrt((double)n);
return ((c * c * c) == n);
}
public static void main(String... args) {
long n = 1;
int squareOnlyCount = 0;
int squareCubeCount = 0;
while ((squareOnlyCount < 30) || (squareCubeCount < 3)) {
long sq = n * n;
if (isPerfectCube(sq)) {
squareCubeCount++;
System.out.println("Square and cube: " + sq);
}
else {
squareOnlyCount++;
System.out.println("Square: " + sq);
}
n++;
}
}
}
```
```txt
Square and cube: 1
Square: 4
Square: 9
Square: 16
Square: 25
Square: 36
Square: 49
Square and cube: 64
Square: 81
Square: 100
Square: 121
Square: 144
Square: 169
Square: 196
Square: 225
Square: 256
Square: 289
Square: 324
Square: 361
Square: 400
Square: 441
Square: 484
Square: 529
Square: 576
Square: 625
Square: 676
Square and cube: 729
Square: 784
Square: 841
Square: 900
Square: 961
Square: 1024
Square: 1089
```
## JavaScript
```javascript
(() => {
'use strict';
const main = () =>
unlines(map(
x => x.toString() + (
isCube(x) ? (
` (cube of ${cubeRootInt(x)} and square of ${
Math.pow(x, 1/2)
})`
) : ''
),
map(x => x * x, enumFromTo(1, 33))
));
// isCube :: Int -> Bool
const isCube = n =>
n === Math.pow(cubeRootInt(n), 3);
// cubeRootInt :: Int -> Int
const cubeRootInt = n => Math.round(Math.pow(n, 1 / 3));
// GENERIC FUNCTIONS ----------------------------------
// enumFromTo :: Int -> Int -> [Int]
const enumFromTo = (m, n) =>
m <= n ? iterateUntil(
x => n <= x,
x => 1 + x,
m
) : [];
// iterateUntil :: (a -> Bool) -> (a -> a) -> a -> [a]
const iterateUntil = (p, f, x) => {
const vs = [x];
let h = x;
while (!p(h))(h = f(h), vs.push(h));
return vs;
};
// map :: (a -> b) -> [a] -> [b]
const map = (f, xs) => xs.map(f);
// unlines :: [String] -> String
const unlines = xs => xs.join('\n');
// MAIN ---
return main();
})();
```
```txt
1 (cube of 1 and square of 1)
4
9
16
25
36
49
64 (cube of 4 and square of 8)
81
100
121
144
169
196
225
256
289
324
361
400
441
484
529
576
625
676
729 (cube of 9 and square of 27)
784
841
900
961
1024
1089
```
## Julia
```Julia
iscube(n) = n == round(Int, cbrt(n))^3
println(collect(Iterators.take((n^2 for n in 1:10^6 if !iscube(n^2)), 30)))
```
[4, 9, 16, 25, 36, 49, 81, 100, 121, 144, 169, 196, 225, 256, 289, 324, 361, 400, 441, 484, 529, 576, 625, 676, 784, 841, 900, 961, 1024, 1089]
## Kotlin
```scala
// Version 1.2.60
fun main(args: Array) {
var n = 1
var count = 0
while (count < 30) {
val sq = n * n
val cr = Math.cbrt(sq.toDouble()).toInt()
if (cr * cr * cr != sq) {
count++
println(sq)
}
else {
println("$sq is square and cube")
}
n++
}
}
```
```txt
Same as Ring example.
```
## Lua
Calculating cube roots with x^(1/3) caused problems with floating-point 'dust' so the Newton-Raphson method is used instead.
```Lua
function nthroot (x, n)
local r = 1
for i = 1, 16 do
r = (((n - 1) * r) + x / (r ^ (n - 1))) / n
end
return r
end
local i, count, sq, cbrt = 0, 0
while count < 30 do
i = i + 1
sq = i * i
-- The next line should say nthroot(sq, 3), right? But this works. Maths, eh?
cbrt = nthroot(i, 3)
if cbrt == math.floor(cbrt) then
print(sq .. " is square and cube")
else
print(sq)
count = count + 1
end
end
```
```txt
1 is square and cube
4
9
16
25
36
49
64 is square and cube
81
100
121
144
169
196
225
256
289
324
361
400
441
484
529
576
625
676
729 is square and cube
784
841
900
961
1024
1089
```
## Nim
```Nim
var count = 0
var n, c, c3 = 1
while count < 30:
var sq = n * n
while c3 < sq:
inc c
c3 = c * c * c
if c3 == sq:
echo $sq, " is square and cube"
else:
echo $sq
inc count
inc n
```
```txt
1 is square and cube
4
9
16
25
36
49
64 is square and cube
81
100
121
144
169
196
225
256
289
324
361
400
441
484
529
576
625
676
729 is square and cube
784
841
900
961
1024
1089
```
## OCaml
```ocaml
let rec fN n g phi =
if phi < 31 then
match compare (n*n) (g*g*g) with
| -1 -> Printf.printf "%d\n" (n*n); fN (n+1) g (phi+1)
| 0 -> Printf.printf "%d cube and square\n" (n*n); fN (n+1) (g+1) phi
| 1 -> fN n (g+1) phi
| _ -> assert false
;;
fN 1 1 1
```
## Pascal
Only using addition :-)
```pascal
program SquareButNotCube;
var
sqN,
sqDelta,
SqNum,
cbN,
cbDelta1,
cbDelta2,
CbNum,
CountSqNotCb,
CountSqAndCb : NativeUint;
begin
CountSqNotCb := 0;
CountSqAndCb := 0;
SqNum := 0;
CbNum := 0;
cbN := 0;
sqN := 0;
sqDelta := 1;
cbDelta1 := 0;
cbDelta2 := 1;
repeat
inc(sqN);
inc(sqNum,sqDelta);
inc(sqDelta,2);
IF sqNum>cbNum then
Begin
inc(cbN);
cbNum := cbNum+cbDelta2;
inc(cbDelta1,6);// 0,6,12,18...
inc(cbDelta2,cbDelta1);//1,7,19,35...
end;
IF sqNum <> cbNUm then
Begin
writeln(sqNum :25);
inc(CountSqNotCb);
end
else
Begin
writeln(sqNum:25,sqN:10,'*',sqN,' = ',cbN,'*',cbN,'*',cbN);
inc(CountSqANDCb);
end;
until CountSqNotCb >= 30;//sqrt(High(NativeUint));
writeln(CountSqANDCb,' where numbers are square and cube ');
end.
```
```txt
1 1*1 = 1*1*1
4
9
16
25
36
49
64 8*8 = 4*4*4
81
100
121
144
169
196
225
256
289
324
361
400
441
484
529
576
625
676
729 27*27 = 9*9*9
784
841
900
961
1024
1089
3 where numbers are square and cube
// there are 1625 numbers which are square and cube < High(Uint64)
//18412815093994140625 4291015625*4291015625 = 2640625*2640625*2640625
```
## Perl
### = Hash =
Use a hash to track state (and avoid floating-point math).
```perl
while ($cnt < 30) {
$n++;
$h{$n**2}++;
$h{$n**3}--;
$cnt++ if $h{$n**2} > 0;
}
print "First 30 positive integers that are a square but not a cube:\n";
print "$_ " for sort { $a <=> $b } grep { $h{$_} == 1 } keys %h;
print "\n\nFirst 3 positive integers that are both a square and a cube:\n";
print "$_ " for sort { $a <=> $b } grep { $h{$_} == 0 } keys %h;
```
```txt
First 30 positive integers that are a square but not a cube:
4 9 16 25 36 49 81 100 121 144 169 196 225 256 289 324 361 400 441 484 529 576 625 676 784 841 900 961 1024 1089
First 3 positive integers that are both a square and a cube:
1 64 729
```
### = Generators =
A more general approach involving generators/closures to implement 'lazy' lists as in the Perl 6 example.
Using ideas and code from the very similar [[Generator_Exponential#Perl 6|Generator exponential]] task.
Output is the same as previous.
```perl
# return an anonymous subroutine that generates stream of specified powers
sub gen_pow {
my $m = shift;
my $e = 1;
return sub { return $e++ ** $m; };
}
# return an anonymous subroutine generator that filters output from supplied generators g1 and g2
sub gen_filter {
my($g1, $g2) = @_;
my $v1;
my $v2 = $g2->();
return sub {
while (1) {
$v1 = $g1->();
$v2 = $g2->() while $v1 > $v2;
return $v1 unless $v1 == $v2;
}
};
}
my $pow2 = gen_pow(2);
my $pow3 = gen_pow(3);
my $squares_without_cubes = gen_filter($pow2, $pow3);
print "First 30 positive integers that are a square but not a cube:\n";
print $squares_without_cubes->() . ' ' for 1..30;
my $pow6 = gen_pow(6);
print "\n\nFirst 3 positive integers that are both a square and a cube:\n";
print $pow6->() . ' ' for 1..3;
```
## Perl 6
```perl6
my @square-and-cube = map { .⁶ }, 1..Inf;
my @square-but-not-cube = (1..Inf).map({ .² }).grep({ $_ ∉ @square-and-cube[^@square-and-cube.first: * > $_, :k]});
put "First 30 positive integers that are a square but not a cube: \n", @square-but-not-cube[^30];
put "\nFirst 15 positive integers that are both a square and a cube: \n", @square-and-cube[^15];
```
```txt
First 30 positive integers that are a square but not a cube:
4 9 16 25 36 49 81 100 121 144 169 196 225 256 289 324 361 400 441 484 529 576 625 676 784 841 900 961 1024 1089
First 15 positive integers that are both a square and a cube:
1 64 729 4096 15625 46656 117649 262144 531441 1000000 1771561 2985984 4826809 7529536 11390625
```
## Phix
```Phix
integer square = 1, squared = 1*1,
cube = 1, cubed = 1*1*1,
count = 0
while count<30 do
squared = square*square
while squared>cubed do cube += 1; cubed = cube*cube*cube end while
if squared=cubed then
printf(1,"%d: %d == %d^3\n",{square,squared,cube})
else
count += 1
printf(1,"%d: %d\n",{square,squared})
end if
square += 1
end while
printf(1,"\nThe first 15 positive integers that are both a square and a cube: \n")
?sq_power(tagset(15),6)
```
```txt
1: 1 == 1^3
2: 4
3: 9
4: 16
5: 25
6: 36
7: 49
8: 64 == 4^3
9: 81
10: 100
11: 121
12: 144
13: 169
14: 196
15: 225
16: 256
17: 289
18: 324
19: 361
20: 400
21: 441
22: 484
23: 529
24: 576
25: 625
26: 676
27: 729 == 9^3
28: 784
29: 841
30: 900
31: 961
32: 1024
33: 1089
The first 15 positive integers that are both a square and a cube:
{1,64,729,4096,15625,46656,117649,262144,531441,1000000,1771561,2985984,4826809,7529536,11390625}
```
## Python
```python
# nonCubeSquares :: Int -> [(Int, Bool)]
def nonCubeSquares(n):
upto = enumFromTo(1)
ns = upto(n)
setCubes = set(x ** 3 for x in ns)
ms = upto(n + len(set(x * x for x in ns).intersection(
setCubes
)))
return list(tuple([x * x, x in setCubes]) for x in ms)
# squareListing :: [(Int, Bool)] -> [String]
def squareListing(xs):
justifyIdx = justifyRight(len(str(1 + len(xs))))(' ')
justifySqr = justifyRight(1 + len(str(xs[-1][0])))(' ')
return list(
'(' + str(1 + idx) + '^2 = ' + str(n) +
' = ' + str(round(n ** (1 / 3))) + '^3)' if bln else (
justifyIdx(1 + idx) + ' ->' +
justifySqr(n)
)
for idx, (n, bln) in enumerate(xs)
)
def main():
print(
unlines(
squareListing(
nonCubeSquares(30)
)
)
)
# GENERIC ------------------------------------------------------------------
# enumFromTo :: Int -> Int -> [Int]
def enumFromTo(m):
return lambda n: list(range(m, 1 + n))
# justifyRight :: Int -> Char -> String -> String
def justifyRight(n):
return lambda cFiller: lambda a: (
((n * cFiller) + str(a))[-n:]
)
# unlines :: [String] -> String
def unlines(xs):
return '\n'.join(xs)
main()
```
```txt
(1^2 = 1 = 1^3)
2 -> 4
3 -> 9
4 -> 16
5 -> 25
6 -> 36
7 -> 49
(8^2 = 64 = 4^3)
9 -> 81
10 -> 100
11 -> 121
12 -> 144
13 -> 169
14 -> 196
15 -> 225
16 -> 256
17 -> 289
18 -> 324
19 -> 361
20 -> 400
21 -> 441
22 -> 484
23 -> 529
24 -> 576
25 -> 625
26 -> 676
(27^2 = 729 = 9^3)
28 -> 784
29 -> 841
30 -> 900
31 -> 961
32 -> 1024
33 -> 1089
```
## Racket
Using a generator it _is_ possible to print the cubes in-line, but I've chosen to show reusing the generator / for / sequence interaction:
```racket
#lang racket
(require racket/generator)
;; generates values:
;; next square
;; cube-root if cube, #f otherwise
(define (make-^2-but-not-^3-generator)
(generator
()
(let loop ((s 1) (c 1))
(let ((s^2 (sqr s)) (c^3 (* c c c)))
(yield s^2 (and (= s^2 c^3) c))
(loop (add1 s) (+ c (if (>= s^2 c^3) 1 0)))))))
(for/list ((x (in-range 1 31))
((s^2 _) (sequence-filter (λ (_ c) (not c)) (in-producer (make-^2-but-not-^3-generator)))))
s^2)
(for ((x (in-range 1 4))
((s^2 c) (sequence-filter (λ (s^2 c) c) (in-producer (make-^2-but-not-^3-generator)))))
(printf "~a: ~a is also ~a^3~%" x s^2 c))
```
```txt
'(4 9 16 25 36 49 81 100 121 144 169 196 225 256 289 324 361 400 441 484 529 576 625 676 784 841 900 961 1024 1089)
1: 1 is also 1^3
2: 64 is also 4^3
3: 729 is also 9^3
```
## REXX
Programming note: extra code was added to support an additional output format (see the 2nd '''output''' section).
```rexx
/*REXX pgm shows N ints>0 that are squares and not cubes, & which are squares and cubes.*/
numeric digits 20 /*be able to handle some large numbers.*/
parse arg N . /*obtain optional argument from the CL.*/
if N=='' | N=="," then N=30 /*Not specified? Then use the default.*/
sqcb= N<0 /*N negative? Then show squares & cubes*/
N = abs(N) /*define N to be the absolute value. */
w= length(N) + 3 /*W: used for aligning output columns.*/
say ' count ' /*display the 1st line of the title. */
say ' ─────── ' /* " " 2nd " " " " */
@.= 0 /*@: stemmed array for computed cubes.*/
#= 0; ##= 0 /*count (integer): squares & not cubes.*/
do j=1 until #==N | ##==N /*loop 'til enough " " " " */
sq= j*j; cube= sq*j; @.cube= 1 /*compute the square of J and the cube.*/
if @.sq then do
##= ## + 1 /*bump the counter of squares and cubs.*/
if \sqcb then counter= left('', 12) /*don't show this counter.*/
else counter= center(##, 12) /* do " " " */
say counter right(sq, 3*w) 'is a square and a cube'
end
else do
if sqcb then iterate
#= # + 1 /*bump the counter of squares & ¬ cubes*/
say center(#, 12) right(sq, 3*w) 'is a square and not a cube'
end
end /*j*/ /*stick a fork in it, we're all done. */
```
```txt
count
───────
1 is a square and a cube
1 4 is a square and not a cube
2 9 is a square and not a cube
3 16 is a square and not a cube
4 25 is a square and not a cube
5 36 is a square and not a cube
6 49 is a square and not a cube
64 is a square and a cube
7 81 is a square and not a cube
8 100 is a square and not a cube
9 121 is a square and not a cube
10 144 is a square and not a cube
11 169 is a square and not a cube
12 196 is a square and not a cube
13 225 is a square and not a cube
14 256 is a square and not a cube
15 289 is a square and not a cube
16 324 is a square and not a cube
17 361 is a square and not a cube
18 400 is a square and not a cube
19 441 is a square and not a cube
20 484 is a square and not a cube
21 529 is a square and not a cube
22 576 is a square and not a cube
23 625 is a square and not a cube
24 676 is a square and not a cube
729 is a square and a cube
25 784 is a square and not a cube
26 841 is a square and not a cube
27 900 is a square and not a cube
28 961 is a square and not a cube
29 1024 is a square and not a cube
30 1089 is a square and not a cube
```
```txt
count
───────
1 1 is a square and a cube
2 64 is a square and a cube
3 729 is a square and a cube
4 4096 is a square and a cube
5 15625 is a square and a cube
6 46656 is a square and a cube
7 117649 is a square and a cube
8 262144 is a square and a cube
9 531441 is a square and a cube
10 1000000 is a square and a cube
11 1771561 is a square and a cube
12 2985984 is a square and a cube
13 4826809 is a square and a cube
14 7529536 is a square and a cube
15 11390625 is a square and a cube
16 16777216 is a square and a cube
17 24137569 is a square and a cube
18 34012224 is a square and a cube
19 47045881 is a square and a cube
20 64000000 is a square and a cube
21 85766121 is a square and a cube
22 113379904 is a square and a cube
23 148035889 is a square and a cube
24 191102976 is a square and a cube
25 244140625 is a square and a cube
26 308915776 is a square and a cube
27 387420489 is a square and a cube
28 481890304 is a square and a cube
29 594823321 is a square and a cube
30 729000000 is a square and a cube
31 887503681 is a square and a cube
32 1073741824 is a square and a cube
33 1291467969 is a square and a cube
34 1544804416 is a square and a cube
35 1838265625 is a square and a cube
36 2176782336 is a square and a cube
37 2565726409 is a square and a cube
38 3010936384 is a square and a cube
39 3518743761 is a square and a cube
40 4096000000 is a square and a cube
41 4750104241 is a square and a cube
42 5489031744 is a square and a cube
43 6321363049 is a square and a cube
44 7256313856 is a square and a cube
45 8303765625 is a square and a cube
46 9474296896 is a square and a cube
47 10779215329 is a square and a cube
48 12230590464 is a square and a cube
49 13841287201 is a square and a cube
50 15625000000 is a square and a cube
51 17596287801 is a square and a cube
52 19770609664 is a square and a cube
53 22164361129 is a square and a cube
54 24794911296 is a square and a cube
55 27680640625 is a square and a cube
```
## Ring
```ring
# Project : Square but not cube
limit = 30
num = 0
sq = 0
while num < limit
sq = sq + 1
sqpow = pow(sq,2)
flag = iscube(sqpow)
if flag = 0
num = num + 1
see sqpow + nl
else
see "" + sqpow + " is square and cube" + nl
ok
end
func iscube(cube)
for n = 1 to cube
if pow(n,3) = cube
return 1
ok
next
return 0
```
Output:
```txt
1 is square and cube
4
9
16
25
36
49
64 is square and cube
81
100
121
144
169
196
225
256
289
324
361
400
441
484
529
576
625
676
729 is square and cube
784
841
900
961
1024
1089
```
## Ruby
```ruby
#!/usr/bin/env ruby
class PowIt
:next
def initialize
@next = 1;
end
end
class SquareIt < PowIt
def next
result = @next ** 2
@next += 1
return result
end
end
class CubeIt < PowIt
def next
result = @next ** 3
@next += 1
return result
end
end
squares = []
hexponents = []
squit = SquareIt.new
cuit = CubeIt.new
s = squit.next
c = cuit.next
while (squares.length < 30 || hexponents.length < 3)
if s < c
squares.push(s) if squares.length < 30
s = squit.next
elsif s == c
hexponents.push(s) if hexponents.length < 3
s = squit.next
c = cuit.next
else
c = cuit.next
end
end
puts "Squares:"
puts squares.join(" ")
puts "Square-and-cubes:"
puts hexponents.join(" ")
```
```txt
Squares:
4 9 16 25 36 49 81 100 121 144 169 196 225 256 289 324 361 400 441 484 529 576 625 676 784 841 900 961 1024 1089
Square-and-cubes:
1 64 729
```
## Scala
This example uses Spire's SafeLongs for both removing any size limitation and making exponentiation/roots cleaner, at the expense of initializing lists with an iteration vs the simpler .from(n). Both the non-cube-squares and square-cubes are lazily evaluated lists, the former is constructed by making lists of square numbers between each pair of cubes and flattening them into one list, the latter is formed by filtering non-squares out of a list of cubes.
```scala
import spire.math.SafeLong
import spire.implicits._
def ncs: LazyList[SafeLong] = LazyList.iterate(SafeLong(1))(_ + 1).flatMap(n => Iterator.iterate(n.pow(3).sqrt + 1)(_ + 1).map(i => i*i).takeWhile(_ < (n + 1).pow(3)))
def scs: LazyList[SafeLong] = LazyList.iterate(SafeLong(1))(_ + 1).map(_.pow(3)).filter(n => n.sqrt.pow(2) == n)
```
```txt
scala> println(ncs.take(30).mkString(", "))
4, 9, 16, 25, 36, 49, 81, 100, 121, 144, 169, 196, 225, 256, 289, 324, 361, 400, 441, 484, 529, 576, 625, 676, 784, 841, 900, 961, 1024, 1089
scala> println(scs.take(3).mkString(", "))
1, 64, 729
```
## Sidef
```ruby
var square_and_cube = Enumerator({|f|
1..Inf -> each {|n| f(n**6) }
})
var square_but_not_cube = Enumerator({|f|
1..Inf -> lazy.map {|n| n**2 }.grep {|n| !n.is_power(3) }.each {|n| f(n) }
})
say "First 30 positive integers that are a square but not a cube:"
say square_but_not_cube.first(30).join(' ')
say "First 15 positive integers that are both a square and a cube:"
say square_and_cube.first(15).join(' ')
```
```txt
First 30 positive integers that are a square but not a cube:
4 9 16 25 36 49 81 100 121 144 169 196 225 256 289 324 361 400 441 484 529 576 625 676 784 841 900 961 1024 1089
First 15 positive integers that are both a square and a cube:
1 64 729 4096 15625 46656 117649 262144 531441 1000000 1771561 2985984 4826809 7529536 11390625
```
## Visual Basic .NET
Inspired by the '''F#''' version, but no longer resembles it. Removed the recursion, multiplying (like the '''D''' and '''Pascal''' versions, only addition is used to calculate squares and cubes), '''match''' (Select Case) statement, and hard-coded limit.
```vbnet
Module Module1
' flag / mask explanation:
' bit 0 (1) = increment square
' bit 1 (2) = increment cube
' bit 2 (4) = has output
' Checks flag against mask, then advances mask.
Function ChkFlg(flag As Integer, ByRef mask As Integer) As Boolean
ChkFlg = (flag And mask) = mask : mask <<= 1
End Function
Sub SwoC(limit As Integer)
Dim count, square, delta, cube, d1, d2, flag, mask As Integer, s as string = ""
count = 1 : square = 1 : delta = 1 : cube = 1 : d1 = 1 : d2 = 0
While count <= limit
flag = {5, 7, 2}(1 + square.CompareTo(cube))
If flag = 7 Then s = String. Format(" {0} (also cube)", square)
If flag = 5 Then s = String.Format("{0,-2} {1}", count, square) : count += 1
mask = 1 : If ChkFlg(flag, mask) Then delta += 2 : square += delta
If ChkFlg(flag, mask) Then d2 += 6 : d1 += d2 : cube += d1
If ChkFlg(flag, mask) Then Console.WriteLine(s)
End While
End Sub
Sub Main()
SwoC(30)
End Sub
End Module
```
```txt
1 (also cube)
1 4
2 9
3 16
4 25
5 36
6 49
64 (also cube)
7 81
8 100
9 121
10 144
11 169
12 196
13 225
14 256
15 289
16 324
17 361
18 400
19 441
20 484
21 529
22 576
23 625
24 676
729 (also cube)
25 784
26 841
27 900
28 961
29 1024
30 1089
```
## zkl
```zkl
println("First 30 positive integers that are a square but not a cube:");
squareButNotCube:=(1).walker(*).tweak(fcn(n){
sq,cr := n*n, sq.toFloat().pow(1.0/3).round(); // cube root(64)<4
if(sq==cr*cr*cr) Void.Skip else sq
});
squareButNotCube.walk(30).concat(",").println("\n");
println("First 15 positive integers that are both a square and a cube:");
println((1).walker(*).tweak((1).pow.unbind().fp1(6)).walk(15));
```
```txt
First 30 positive integers that are a square but not a cube:
4,9,16,25,36,49,81,100,121,144,169,196,225,256,289,324,361,400,441,484,529,576,625,676,784,841,900,961,1024,1089
First 15 positive integers that are both a square and a cube:
L(1,64,729,4096,15625,46656,117649,262144,531441,1000000,1771561,2985984,4826809,7529536,11390625
```