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This means it might contain formatting issues, incorrect code, conceptual problems, or other severe issues.
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{{draft task}} Given a stream of characters, presumably (simulated) from a keyboard, that contain the separators "formfeed", "linefeed", "tab" and "space" characters. Print out the ith character of the ith tab-field of the ith line of the ith page to reveal a secret password.
Stop processing immediately upon encountering a "!" found uniquely in this i,i,i,i position (least the system self destruct). The "!" may be found/permitted else where however, in which case it should be ignored.
Ideally this can be generalise as follows:
- The separators (formfeed, linefeed, tab, space) provided from a user supplied array and can include additional/alternative separators, e.g. (formfeed, linefeed, ".", "," ," ",...).
- These selection criterial is generalised ith,ith,ith,ith to a boolean function of f(page,line,field,word,...) or f(ith,jth,kth,lth,mth,etc...)
Provide a reasonably interesting message to be decoded, e.g. Silence-Dogood. Your choice.
This task was inspired by the movie "[[wp:National_Treasure_%28film%29|National Treasure]]" with refers to a "[[wp:Book cipher|book cipher]]".
C
{{trans|C++}}
#include <stdbool.h> #include <stdio.h> #include <stdlib.h> struct UserInput { char formFeed; char lineFeed; char tab; char space; }; struct UserInputNode { struct UserInput ui; struct UserInputNode *next; }; bool decode(FILE *fp, const struct UserInput ui) { char f = 0, l = 0, t = 0, s = 0; char buffer[1]; while (fread(buffer, 1, 1, fp)) { char c = buffer[0]; if (f == ui.formFeed && l == ui.lineFeed && t == ui.tab && s == ui.space) { if (c == '!') return false; putchar(c); return true; } else if (c == '\f') { f++; l = t = s = 0; } else if (c == '\n') { l++; t = s = 0; } else if (c == '\t') { t++; s = 0; } else { s++; } } return false; } void decodeFile(char *fileName, struct UserInputNode *uin) { FILE *fp; fp = fopen(fileName, "r"); if (NULL == fp) { fprintf(stderr, "Could not find %s\n", fileName); return; } if (NULL == uin) { fprintf(stderr, "No user input detected!\n"); return; } while (NULL != uin) { if (!decode(fp, uin->ui)) { break; } fseek(fp, 0, SEEK_SET); uin = uin->next; } printf("\n\n"); } struct UserInputNode *getUserInput() { struct UserInputNode *uip, *temp; // 0 18 0 0 temp = malloc(sizeof(struct UserInputNode)); temp->ui.formFeed = 0; temp->ui.lineFeed = 18; temp->ui.tab = 0; temp->ui.space = 0; uip = temp; // 0 68 0 1 temp->next = malloc(sizeof(struct UserInputNode)); temp = temp->next; temp->ui.formFeed = 0; temp->ui.lineFeed = 68; temp->ui.tab = 0; temp->ui.space = 1; // 0 100 0 32 temp->next = malloc(sizeof(struct UserInputNode)); temp = temp->next; temp->ui.formFeed = 0; temp->ui.lineFeed = 100; temp->ui.tab = 0; temp->ui.space = 32; // 0 114 0 45 temp->next = malloc(sizeof(struct UserInputNode)); temp = temp->next; temp->ui.formFeed = 0; temp->ui.lineFeed = 114; temp->ui.tab = 0; temp->ui.space = 45; // 0 38 0 26 temp->next = malloc(sizeof(struct UserInputNode)); temp = temp->next; temp->ui.formFeed = 0; temp->ui.lineFeed = 38; temp->ui.tab = 0; temp->ui.space = 26; // 0 16 0 21 temp->next = malloc(sizeof(struct UserInputNode)); temp = temp->next; temp->ui.formFeed = 0; temp->ui.lineFeed = 16; temp->ui.tab = 0; temp->ui.space = 21; // 0 17 0 59 temp->next = malloc(sizeof(struct UserInputNode)); temp = temp->next; temp->ui.formFeed = 0; temp->ui.lineFeed = 17; temp->ui.tab = 0; temp->ui.space = 59; // 0 11 0 29 temp->next = malloc(sizeof(struct UserInputNode)); temp = temp->next; temp->ui.formFeed = 0; temp->ui.lineFeed = 11; temp->ui.tab = 0; temp->ui.space = 29; // 0 102 0 0 temp->next = malloc(sizeof(struct UserInputNode)); temp = temp->next; temp->ui.formFeed = 0; temp->ui.lineFeed = 102; temp->ui.tab = 0; temp->ui.space = 0; // 0 10 0 50 temp->next = malloc(sizeof(struct UserInputNode)); temp = temp->next; temp->ui.formFeed = 0; temp->ui.lineFeed = 10; temp->ui.tab = 0; temp->ui.space = 50; // 0 39 0 42 temp->next = malloc(sizeof(struct UserInputNode)); temp = temp->next; temp->ui.formFeed = 0; temp->ui.lineFeed = 39; temp->ui.tab = 0; temp->ui.space = 42; // 0 33 0 50 temp->next = malloc(sizeof(struct UserInputNode)); temp = temp->next; temp->ui.formFeed = 0; temp->ui.lineFeed = 33; temp->ui.tab = 0; temp->ui.space = 50; // 0 46 0 54 temp->next = malloc(sizeof(struct UserInputNode)); temp = temp->next; temp->ui.formFeed = 0; temp->ui.lineFeed = 46; temp->ui.tab = 0; temp->ui.space = 54; // 0 76 0 47 temp->next = malloc(sizeof(struct UserInputNode)); temp = temp->next; temp->ui.formFeed = 0; temp->ui.lineFeed = 76; temp->ui.tab = 0; temp->ui.space = 47; // 0 84 2 28 temp->next = malloc(sizeof(struct UserInputNode)); temp = temp->next; temp->ui.formFeed = 0; temp->ui.lineFeed = 84; temp->ui.tab = 2; temp->ui.space = 28; temp->next = NULL; return uip; } void freeUserInput(struct UserInputNode *uip) { if (NULL == uip) { return; } freeUserInput(uip->next); uip->next = NULL; free(uip); } int main() { struct UserInputNode *uip; uip = getUserInput(); decodeFile("theRaven.txt", uip); freeUserInput(uip); return 0; }
{{out}}
Silence-Dogood.
C++
Text used to encode:[http://paulo-jorente.de/text/theRaven.txt The Raven - by E.A.Poe]
#include <vector> #include <iostream> #include <fstream> #include <sstream> typedef struct { int s[4]; }userI; class jit{ public: void decode( std::string& file, std::vector<userI>& ui ) { std::ifstream f( file.c_str(), std::ios_base::in ); fileBuffer = std::string( ( std::istreambuf_iterator<char>( f ) ), std::istreambuf_iterator<char>() ); f.close(); for( std::vector<userI>::iterator t = ui.begin(); t != ui.end(); t++ ) { if( !decode( ( *t ).s ) ) break; } std::cout << "\n\n"; } private: bool decode( int* ui ) { int l = 0, t = 0, p = 0, c = 0, a = 0; for( std::string::iterator i = fileBuffer.begin(); i != fileBuffer.end(); i++ ) { if( p == ui[0] && l == ui[1] && t == ui[2] && c == ui[3] ) { if( *i == '!' ) return false; std::cout << *i; return true; } if( *i == '\n' ) { l++; t = c = 0; } else if( *i == '\t' ) { t++; c = 0; } else if( *i == '\f' ) { p++; l = t = c = 0; } else { c++;} } return false; } std::string fileBuffer; }; void getUserInput( std::vector<userI>& u ) { std::string h = "0 18 0 0 0 68 0 1 0 100 0 32 0 114 0 45 0 38 0 26 0 16 0 21 0 17 0 59 0 11 " "0 29 0 102 0 0 0 10 0 50 0 39 0 42 0 33 0 50 0 46 0 54 0 76 0 47 0 84 2 28"; //std::getline( std::cin, h ); std::stringstream ss( h ); userI a; int x = 0; while( std::getline( ss, h, ' ' ) ) { a.s[x] = atoi( h.c_str() ); if( ++x == 4 ) { u.push_back( a ); x = 0; } } } int main( int argc, char* argv[] ) { std::vector<userI> ui; getUserInput( ui ); jit j; j.decode( std::string( "theRaven.txt" ), ui ); return 0; }
{{out}}
Silence-Dogood.
C#
{{trans|D}}
using System; using System.Collections.Generic; using System.Linq; namespace JustInTimeProcessing { struct UserInput { public UserInput(string ff, string lf, string tb, string sp) { FormFeed = (char)int.Parse(ff); LineFeed = (char)int.Parse(lf); Tab = (char)int.Parse(tb); Space = (char)int.Parse(sp); } public char FormFeed { get; } public char LineFeed { get; } public char Tab { get; } public char Space { get; } } class Program { static List<UserInput> GetUserInput() { string h = "0 18 0 0 0 68 0 1 0 100 0 32 0 114 0 45 0 38 0 26 0 16 0 21 0 17 0 59 0 11 " + "0 29 0 102 0 0 0 10 0 50 0 39 0 42 0 33 0 50 0 46 0 54 0 76 0 47 0 84 2 28"; return h.Split(' ') .Select((x, idx) => new { x, idx }) .GroupBy(x => x.idx / 4) //.Select(g => g.Select(a => a.x)) .Select(g => { var ge = g.Select(a => a.x).ToArray(); return new UserInput(ge[0], ge[1], ge[2], ge[3]); }) .ToList(); } static void Decode(string filename, List<UserInput> uiList) { string text = System.IO.File.ReadAllText(filename); bool Decode2(UserInput ui) { char f = (char)0; char l = (char)0; char t = (char)0; char s = (char)0; foreach (char c in text) { if (f == ui.FormFeed && l == ui.LineFeed && t == ui.Tab && s == ui.Space) { if (c == '!') return false; Console.Write(c); return true; } if (c == '\u000c') { f++; l = (char)0; t = (char)0; s = (char)0; } else if (c == '\n') { l++; t = (char)0; s = (char)0; } else if (c == '\t') { t++; s = (char)0; } else { s++; } } return false; } foreach (UserInput ui in uiList) { if (!Decode2(ui)) { break; } } Console.WriteLine(); } static void Main(string[] args) { var uiList = GetUserInput(); Decode("theraven.txt", uiList); Console.ReadLine(); } } }
{{out}}
Silence-Dogood.
D
{{trans|Kotlin}}
import std.algorithm; import std.array; import std.conv; import std.file; import std.range; import std.stdio; struct UserInput { char formFeed; char lineFeed; char tab; char space; this(string ff, string lf, string tb, string sp) { formFeed = cast(char) ff.to!int; lineFeed = cast(char) lf.to!int; tab = cast(char) tb.to!int; space = cast(char) sp.to!int; } } auto getUserInput() { auto h = "0 18 0 0 0 68 0 1 0 100 0 32 0 114 0 45 0 38 0 26 0 16 0 21 0 17 0 59 0 11 " ~ "0 29 0 102 0 0 0 10 0 50 0 39 0 42 0 33 0 50 0 46 0 54 0 76 0 47 0 84 2 28"; auto ctor = (string[] a) => UserInput(a[0], a[1], a[2], a[3]); return h.split(' ').chunks(4).map!ctor.array; } void decode(string fileName, UserInput[] uiList) { auto text = readText(fileName); bool decode2(UserInput ui) { char f = 0; char l = 0; char t = 0; char s = 0; foreach (c; text) { if (f == ui.formFeed && l == ui.lineFeed && t == ui.tab && s == ui.space) { if (c == '!') return false; write(c); return true; } if (c == '\u000c') { f++; l=0; t=0; s=0; } else if (c == '\n') { l++; t=0; s=0; } else if (c == '\t') { t++; s=0; } else { s++; } } return false; } foreach (ui; uiList) { if (!decode2(ui)) break; } writeln; } void main() { auto uiList = getUserInput(); decode("theRaven.txt", uiList); }
{{out}}
Silence-Dogood.
Go
{{trans|C++}}
package main import ( "fmt" "io/ioutil" "log" "strconv" "strings" ) type userInput struct{ formFeed, lineFeed, tab, space int } func getUserInput() []userInput { h := "0 18 0 0 0 68 0 1 0 100 0 32 0 114 0 45 0 38 0 26 0 16 0 21 0 17 0 59 0 11 " + "0 29 0 102 0 0 0 10 0 50 0 39 0 42 0 33 0 50 0 46 0 54 0 76 0 47 0 84 2 28" flds := strings.Fields(h) var uis []userInput var uif [4]int for i := 0; i < len(flds); i += 4 { for j := 0; j < 4; j++ { uif[j], _ = strconv.Atoi(flds[i+j]) } uis = append(uis, userInput{uif[0], uif[1], uif[2], uif[3]}) } return uis } func decode(fileName string, uis []userInput) error { text, err := ioutil.ReadFile(fileName) if err != nil { return err } decode2 := func(ui userInput) bool { var f, l, t, s int for _, c := range text { if f == ui.formFeed && l == ui.lineFeed && t == ui.tab && s == ui.space { if c == '!' { return false } fmt.Printf("%c", c) return true } switch c { case '\f': f++ l = 0 t = 0 s = 0 case '\n': l++ t = 0 s = 0 case '\t': t++ s = 0 default: s++ } } return true } for _, ui := range uis { if !decode2(ui) { break } } fmt.Println() return nil } func main() { uis := getUserInput() err := decode("theRaven.txt", uis) if err != nil { log.Fatal(err) } }
{{out}}
Silence-Dogood.
Java
{{trans|Kotlin}}
import java.io.IOException; import java.nio.charset.StandardCharsets; import java.nio.file.Files; import java.nio.file.Path; import java.nio.file.Paths; import java.util.ArrayList; import java.util.List; import java.util.function.Predicate; public class Processing { private static class UserInput { private char formFeed; private char lineFeed; private char tab; private char space; private UserInput(char formFeed, char lineFeed, char tab, char space) { this.formFeed = formFeed; this.lineFeed = lineFeed; this.tab = tab; this.space = space; } char getFormFeed() { return formFeed; } char getLineFeed() { return lineFeed; } char getTab() { return tab; } char getSpace() { return space; } } private static List<UserInput> getUserInput() { String h = "0 18 0 0 0 68 0 1 0 100 0 32 0 114 0 45 0 38 0 26 0 16 0 21 0 17 0 59 0 11 " + "0 29 0 102 0 0 0 10 0 50 0 39 0 42 0 33 0 50 0 46 0 54 0 76 0 47 0 84 2 28"; String[] s = h.split(" "); List<UserInput> uiList = new ArrayList<>(); for (int idx = 0; idx + 3 < s.length; idx += 4) { char c0 = (char) Integer.parseInt(s[idx + 0]); char c1 = (char) Integer.parseInt(s[idx + 1]); char c2 = (char) Integer.parseInt(s[idx + 2]); char c3 = (char) Integer.parseInt(s[idx + 3]); UserInput userInput = new UserInput(c0, c1, c2, c3); uiList.add(userInput); } return uiList; } private static void decode(String fileName, List<UserInput> uiList) throws IOException { Path path = Paths.get(fileName); byte[] bytes = Files.readAllBytes(path); String text = new String(bytes, StandardCharsets.UTF_8); Predicate<UserInput> decode2 = (UserInput ui) -> { char f = 0; char l = 0; char t = 0; char s = 0; char ff = ui.getFormFeed(); char lf = ui.getLineFeed(); char tb = ui.getTab(); char sp = ui.getSpace(); for (char c : text.toCharArray()) { if (f == ff && l == lf && t == tb && s == sp) { if (c == '!') { return false; } System.out.print(c); return true; } switch (c) { case '\u000c': f++; l = 0; t = 0; s = 0; break; case '\n': l++; t = 0; s = 0; break; case '\t': t++; s = 0; break; default: s++; break; } } return false; }; for (UserInput ui : uiList) { if (!decode2.test(ui)) { break; } } System.out.println(); } public static void main(String[] args) throws IOException { List<UserInput> uiList = getUserInput(); decode("theRaven.txt", uiList); } }
{{out}}
Silence-Dogood.
Julia
Customization is via adding to or deleting from the chars dictionary.
@enum streamstate GET_FF GET_LF GET_TAB GET_CHAR ABORT chars = Dict(GET_FF => ['\f'], GET_LF => ['\n'], GET_TAB => ['\t']) function stream_decode_jit(iostream) msg, state, ffcount, lfcount, tabcount, charcount = "", GET_FF, 0, 0, 0, 0 while true if state == ABORT || eof(iostream) return msg end ch = read(iostream, Char) if state == GET_FF && ch in chars[GET_FF] ffcount += 1 state = GET_LF lfcount = 0 elseif state == GET_LF && ch in chars[GET_LF] if (lfcount += 1) == ffcount state = GET_TAB tabcount = 0 end elseif state == GET_TAB && ch in chars[GET_TAB] if (tabcount += 1) == ffcount state = GET_CHAR charcount = 0 end elseif state == GET_CHAR if (charcount += 1) == ffcount print(ch) msg *= ch if ch == '!' state = ABORT else state = GET_FF end end end end end stream_decode_jit(open("filename.txt", "r"))
Kotlin
{{trans|C++}}
// version 1.2.10 import java.io.File data class UserInput(val formFeed: Int, val lineFeed: Int, val tab: Int, val space: Int) fun getUserInput(): List<UserInput> { val h = "0 18 0 0 0 68 0 1 0 100 0 32 0 114 0 45 0 38 0 26 0 16 0 21 0 17 0 59 0 11 " + "0 29 0 102 0 0 0 10 0 50 0 39 0 42 0 33 0 50 0 46 0 54 0 76 0 47 0 84 2 28" return h.split(' ').chunked(4).map { val (ff, lf, tb, sp) = it UserInput(ff.toInt(), lf.toInt(), tb.toInt(), sp.toInt()) } } fun decode(fileName: String, uiList: List<UserInput>) { val text = File(fileName).readText() fun decode2(ui: UserInput): Boolean { var f = 0 var l = 0 var t = 0 var s = 0 val (ff, lf, tb, sp) = ui for (c in text) { if (f == ff && l == lf && t == tb && s == sp) { if (c == '!') return false print(c) return true } when (c) { '\u000c' -> { f++; l = 0; t = 0; s = 0 } '\n' -> { l++; t = 0; s = 0 } '\t' -> { t++; s = 0 } else -> { s++ } } } return false } for (ui in uiList) { if (!decode2(ui)) break } println() } fun main(args: Array<String>) { val uiList = getUserInput() decode("theRaven.txt", uiList) }
{{out}}
Silence-Dogood.
Perl
{{trans|Perl 6}} {{libheader|ntheory}}
use strict; use warnings; use feature 'say'; use feature 'state'; use ntheory qw/fromdigits todigitstring/; my $key = 'perl5'; srand fromdigits($key,36) % 2**63; my @stream; sub stream { my($i) = shift; state @chars; push @chars, chr($_) for 14..127; $stream[$i] = $chars[rand 1+127-14] unless $stream[$i]; } sub jit_encode { my($str) = shift; my $i = 0; my $last = 0; my $enc = ''; for my $c (split '', $str) { my $h; my $l = ''; ++$i until $c eq stream($i); my $o = $i - $last; $l = $o % 26; $h = $o - $l if $o > 26; $l += 10; $enc .= ($h ? uc todigitstring($h,36) : '') . lc todigitstring($l,36); $last = $i; } $enc } sub jit_decode { my($str) = shift; my @matches = $str =~ /((.*?) ([a-z]))/gx; my $dec = ''; my $i = 0; for my $j (0 .. @matches/3 - 1) { my $o = ( fromdigits($matches[3*$j+1],36) - 10 // 0) + ( fromdigits($matches[3*$j+2],36) // 0); $i += $o; $dec .= $stream[$i]; } $dec } my $enc = jit_encode('The slithey toves did gyre and gimble in the wabe'); say my $result = "Encoded\n$enc\n\nDecoded\n" . jit_decode($enc);
{{out}}
Encoded
bQh52yf9Ex2Wi4Cv1GcyoAUcBKbke3Mo5Ss2WybQlvQs1GviQc1GnQg5Sv26j1Gm26m3Mp26iQz78lQx2Wel1Gcs52y5Sds3Me26l52au1Gwe1Gl
Decoded
The slithey toves did gyre and gimble in the wabe
Perl 6
{{works with|Rakudo|2019.03}}
This is a something of a toy encoder / decoder and probably shouldn't be used for anything serious.
Default encode/decode key is 'Perl 6' Feed it a pass phrase at the command line to use that instead.
Will handle any visible character in the ASCII range as well as space and new-line.
#`[
Set srand to set the encode / decode "key".
Need to use the same "key" and same implementation
of Perl 6 to encode / decode. Gain "security" by
exchanging "keys" by a second channel. Default
"key" is "Perl 6"
]
unit sub MAIN ($key = 'Perl 6');
srand $key.comb(/<.alnum>/).join.parse-base(36) % 2**63;
my @stream = (flat "\n", ' ' .. '~').roll(*);
sub jit-encode (Str $str) {
my $i = 0;
my $last = 0;
my $enc = '';
for $str.comb -> $c {
my $h;
my $l = '';
++$i until $i > 1 && $c eq @stream[$i];
my $o = $i - $last;
$l = $o % 26;
$h = $o - $l if $o >= 26;
$l += 10;
$enc ~= ($h ?? $h.base(36).uc !! '') ~ ($l.base(36).lc);
$last = $i;
}
my $block = 60;
$enc.comb($block).join: "\n"
}
sub jit-decode (Str $str is copy) {
$str.=subst("\n", '', :g);
$str ~~ m:g/((.*?) (<:Ll>))/;
my $dec = '';
my $i = 0;
for $/.List -> $l {
my $o = ($l[0][1].Str.parse-base(36) - 10 // 0) +
($l[0][0].Str.parse-base(36) // 0);
$i += $o;
$dec ~= @stream[$i];
}
$dec
}
my $secret = q:to/END/;
In my opinion, this task is pretty silly.
'Twas brillig, and the slithy toves
Did gyre and gimble in the wabe.
!@#$%^&*()_+}{[].,><\|/?'";:1234567890
END
say "== Secret: ==\n$secret";
say "\n== Encoded: ==";
say my $enc = jit-encode($secret);
say "\n== Decoded: ==";
say jit-decode($enc);
== Secret: ==
In my opinion, this task is pretty silly.
'Twas brillig, and the slithy toves
Did gyre and gimble in the wabe.
!@#$%^&*()_+}{[].,><\|/?'";:1234567890
== Encoded: ==
26j52d6Ie1Ge4Cd26po1GdsQa3Ms52piQd4Cn3Md2Wcf1GtciQz1GwQb5Si2
WnQlQmQjQv1GmQra2Wt4Cpc1Gysatu26va1Gq52x4Cp1Gv4CeQv1Gb1Gp4Co
6IbaQyAUmd26a7Yw3Mh2Wu26v1GfQsQwbQpn26z1Gi1Gl1GmQb1Gfs26v4Ce
Qy2Wm78xaaa4Cj26x6If3Msqu2Wx2Wku1Gh52ydQh3Mb78rll1GvcQap5Sgy
Qm26s1Gh26clj1Gm1GzA4y26bat1Gdk1Gs1Gpm1GlQs7Ys52dQw1Giv5Se5S
u3Mb1Gucn4Cq26h26pQq2Wh5Sh7Yi8OrpQl26p26i3MqtQiQhQi4Ckb3Mi
== Decoded: ==
In my opinion, this task is pretty silly.
'Twas brillig, and the slithy toves
Did gyre and gimble in the wabe.
!@#$%^&*()_+}{[].,><\|/?'";:1234567890
Phix
{{trans|C}}
-- demo/rosetta/BookCipher.exw
function decode(integer fn, sequence ui)
integer {ff,lf,tab,sp} = ui,
f = 0, l = 0, t = 0, s = 0
while true do
integer c = getc(fn)
if c=-1 then return false end if
if f==ff and l==lf and t==tab and s==sp then
if c=='!' then return false end if
puts(1,c)
return true
elsif c==#0C then
f += 1
{l, t, s} @= 0
elsif c=='\n' then
l += 1
{t, s} @= 0
elsif c=='\t' then
t += 1
s = 0
else
s += 1
end if
end while
return false
end function
include builtins\libcurl.e
procedure decodeFile(string filename, url, sequence code)
if not file_exists(filename) then
printf(1,"Downloading %s...\n",{filename})
CURLcode res = curl_easy_get_file(url,"",filename) -- (no proxy)
if res!=CURLE_OK then
string error = sprintf("%d",res)
if res=CURLE_COULDNT_RESOLVE_HOST then
error &= " [CURLE_COULDNT_RESOLVE_HOST]"
end if
crash("Error %s downloading file\n", {error})
end if
end if
integer fn = open(filename, "r")
if fn=-1 then crash("could not open %s",{filename}) end if
for i=1 to length(code) do
if not decode(fn,code[i]) then exit end if
if seek(fn, 0)!=SEEK_OK then crash("seek error") end if
end for
printf(1,"\n\n");
end procedure
constant code = {{0,18,0,0},
{0,68,0,1},
{0,100,0,32},
{0,114,0,45},
{0,38,0,26},
{0,16,0,21},
{0,17,0,59},
{0,11,0,29},
{0,102,0,0},
{0,10,0,50},
{0,39,0,42},
{0,33,0,50},
{0,46,0,54},
{0,76,0,47},
{0,84,2,28}}
decodeFile("theRaven.txt", "http://paulo-jorente.de/text/theRaven.txt", code)
{} = wait_key()
{{out}}
Silence-Dogood.
Python
{{trans|D}}
import sys class UserInput: def __init__(self,chunk): self.formFeed = int(chunk[0]) self.lineFeed = int(chunk[1]) self.tab = int(chunk[2]) self.space = int(chunk[3]) def __str__(self): return "(ff=%d; lf=%d; tb=%d; sp%d)" % (self.formFeed,self.lineFeed,self.tab,self.space) def chunks(l,n): for i in xrange(0, len(l), n): yield l[i:i+n] def getUserInput(): h = "0 18 0 0 0 68 0 1 0 100 0 32 0 114 0 45 0 38 0 26 0 16 0 21 0 17 0 59 0 11 "\ "0 29 0 102 0 0 0 10 0 50 0 39 0 42 0 33 0 50 0 46 0 54 0 76 0 47 0 84 2 28" ha = h.split() return [UserInput(chunk) for chunk in chunks(ha, 4)] def decode(filename,uiList): f = open(filename, "r") text = f.read() def decode2(ui): f = 0 l = 0 t = 0 s = 0 for c in text: if f == ui.formFeed and l == ui.lineFeed and t == ui.tab and s == ui.space: if c == '!': return False sys.stdout.write(c) return True if c == '\u000c': f=f+1 l=0 t=0 s=0 elif c == '\n': l=l+1 t=0 s=0 elif c == '\t': t=t+1 s=0 else: s=s+1 return False for ui in uiList: if not decode2(ui): break print ##### Main ##### uiList = getUserInput() decode("theRaven.txt", uiList)
{{out}}
Silence-Dogood.
Racket
{{trans|Kotlin}}
#lang racket
(define user-input
(~a "0 18 0 0 0 68 0 1 0 100 0 32 0 114 0 45 0 38 0 26 0 16 0 21 0 17 0 59 0 11 "
"0 29 0 102 0 0 0 10 0 50 0 39 0 42 0 33 0 50 0 46 0 54 0 76 0 47 0 84 2 28"))
(define content (file->string "theRaven.txt"))
(define (decode slice)
(match-define (list ff lf tb sp) slice)
(let loop ([f 0] [l 0] [t 0] [s 0] [xs (string->list content)])
(define next (curryr loop (rest xs)))
(match (first xs)
[c #:when (and (= f ff) (= l lf) (= t tb) (= s sp)) c]
[#\u000c (next (add1 f) 0 0 0)]
[#\newline (next f (add1 l) 0 0)]
[#\tab (next f l (add1 t) 0)]
[_ (next f l t (add1 s))])))
(for ([slice (in-slice 4 (map string->number (string-split user-input)))])
(define c (decode slice))
#:break (char=? #\! c)
(display c))
{{in}} http://paulo-jorente.de/text/theRaven.txt
{{out}}
Silence-Dogood.
REXX
The input file used by this REXX program only contains one page; it has no ''FF'' (''formfeed'') characters in it),
and the injection of ''FF'' characters into the file would be like putting pencil marks into a holy book. ☺
/*REXX program extracts characters by using a book cipher (that is a text file). */
parse arg iFID . /*obtain optional name of file (book).*/
if iFID=='' | iFID=="," then iFID= 'JIT.TXT' /*Not specified? Then use the default.*/
$= 'abcdefghijklmnopqrstuvwxyz'; _=$; upper _; $= "0123456789"$ || _; $$=$ || xrange()
prompt= '────────── enter four positive integers or Quit'
pag=1; lin=1; FF= 'c'x /*assume start of page 1, line 1. */
@.= /*read the entire book from the file. */
do while lines(iFID)\==0 /*process lines from input stream(file)*/
_= translate( linein(iFID), , '9'x) /*obtain a single line from input file.*/
if pos(FF, _)\==0 then do; pag=pag+1; lin=1 /*bump page counter; reset line counter*/
end /* [↑] handle finding of FF (formfeed)*/
@.pag.lin= _ /*obtain a single line from input file.*/
lin= lin + 1 /*bump the line counter. */
end /*while*/ /* [↑] read the entire input stream. */
?= /*define the phrase to be null (so far)*/
do ask=0; say prompt; pull y /*get just─in─time positional numbers. */
if abbrev('QUIT', y, 1) then exit 0 /*the user wants out of here, so exit. */
y=space( translate(y, $, $$) ) /*allow any separator the user wants. */
parse var y a.1 a.2 a.3 a.4 /*parse the pertinent parameters. */
if words(y)>4 then do; say 'too many parameters entered.'
iterate ask
end /*go and try again to obtain the parms.*/
do k=1 for 4; is#= datatype(a.k, 'W') /*validate parms {positive integers}.*/
if is# then a.k= a.k / 1 /*normalize the number (for indexing). */
if is# & a.k>0 then iterate /*found a good parameter? Then skip. */
say 'parameter ' k " is missing or not a positive integer: " a.k
iterate ask /*go and ask for another set of parms. */
end /*k*/ /* [↑] done with the validations. */
parse value a.1 a.2 a.3 a.4 with p L w c /*parse parameters for specific names. */
x=substr( word( @.p.L, w), c, 1) /*extract a character from the book. */
if x=='!' then leave /*if the stop char was found, done. */
say right(x '◄─── a letter', 46) /*might as well echo char to terminal. */
?= ? || x /*append the character to the phrase. */
end /*j*/ /* [↑] display letters found in book. */
say '═════►' ? /*stick a fork in it, we're all done. */
{{out|input|text= supplied to the console (terminal) by the user in response to the prompts, (the commas are optional):}}
1, 133, 4, 5
1, 34, 9, 3
1, 1377, 2, 2
1, 4, 8, 4
1, 265, 3, 5
1, 413, 10, 2
1, 10, 12, 1
1, 144, 10, 10
1, 571, 4, 12
{{out|input|text= (abbridged)}}
──────────enter four parameters (all positive integers) or QUIT
1, 133, 4, 5 ◄■■■■■■■■■ user input (first reponse).
s ◄─── a letter
∙
∙ (some prompts and reponses elided.)
∙
──────────enter four parameters (all positive integers) or QUIT
1, 571, 4, 12 ◄■■■■■■■■■ user input (ninth reponse).
═════► so─true.
The input file used (the IBM jargon file) in the above REXX program can be found here ───► [[Just_in_time_processing_on_a_character_stream/REXX/JIT.TXT]].
Tcl
{{works with|Tcl|8.6}}
package require Tcl 8.6 oo::class create JustInTimeStreamExtract { variable map counter counters last constructor {{pageSeparator "\f"} {lineSeparator "\n"} {fieldSeparator "\t"}} { dict set map $pageSeparator NextPage dict set map $lineSeparator NextLine dict set map $fieldSeparator NextField set counter 1 array set counters {page 0 line 0 field 0 char 0} set last "" } method emit {char} { puts -nonewline $char set last $char } method finished {} { if {$last ne "\n"} { puts "" } } method stream {{channel stdin} {length 1}} { try { while 1 { set str [read $channel $length] if {[eof $channel]} break foreach c [split $str ""] { if {[dict exists $map $c]} { my [dict get $map $c] } else { my NextChar $c } } } } trap STOP {} { # Do nothing } my finished } method NextPage {} { incr counters(page) array set counters {line 0 field 0 char 0} } method NextLine {} { incr counters(line) array set counters {field 0 char 0} } method NextField {} { incr counters(field) set counters(char) 0 } method NextChar {char} { incr counters(char) if {[my PrintThisOne?]} { if {$char eq "!"} { throw STOP "stop character found" } incr counter my emit $char array set counters {page 0 line 0 field 0 char 0} } } method PrintThisOne? {} { tcl::mathop::== $counter $counters(page) $counters(line) $counters(field) $counters(char) } }
Demonstration of use:
[JustInTimeStreamExtract new] stream [open "sample.txt"]
zkl
{{trans|C++}}
class FlyBy{
fcn decode(file,tuplets){
codePad:=File(file).read().mode(String); // blob of text
tuplets.pump(Console.print, _decode.fp1(codePad));
println();
}
fcn [private] _decode(idx,codePad){ // idx is (ff,lf,tab,chr) offset info codePad
z:=-1;
foreach n,c in (idx.zip(T("\f","\n","\t"))){
do(n){ if(Void==(z=codePad.find(c,z+1))) return(Void.Stop); }
}
if(z==-1) z=0; // (0,0,0,n)
try{ return(codePad[z + idx[-1] + 1]) }catch{ return(Void.Stop) }
}
}
fcn getUserInput{
// I don't know a user would enter this but we have
// a string of 4 item tuplets : (formfeeds, linefeeds, tabs, characters), ...
// each tuplet is an offset into a code pad (text)
h:="0 18 0 0 0 68 0 1 0 100 0 32 0 114 0 45 0 38 0 26 0 16 0 21 0 17 0 59 0 11 "
"0 29 0 102 0 0 0 10 0 50 0 39 0 42 0 33 0 50 0 46 0 54 0 76 0 47 0 84 2 28";
h.split(" ").pump(List,T(Void.Read,3),
fcn(ff,lf,t,s){ vm.arglist.apply("toInt") });
}
input:=getUserInput();
// our code pad is: http://paulo-jorente.de/text/theRaven.txt
FlyBy.decode("theRaven.txt",input);
{{out}}
Silence-Dogood.