Hi, Monks.

I have a problem finding all permutations of a string. For example given {a|b}cd{f|g|h} i must get:

acdf
bcdf
acdg
...
bcdh

The main problem for me here is that original string may have unknown number of token {} (here we have only two but sometimes it's seven).

Here is my code (but it doesn't produce output i need):

#!/usr/bin/perl -w
use strict;
use warnings;

my $input_text;
open my $input_fh, "input.txt" or die $!;

{
    local $/;
    $input_text = <$input_fh>;
}

close $input_fh;

my @tokens;
my $number = 1;
while ( $input_text =~ m/\{([^\}]+)}/isxg ) {
    
    push @tokens, {
        
        values => [ split /\|/, $1 ],
        name => "%TOKEN_$number%",
    };
    
    $input_text =~ s/\{([^\}]+)}/%TOKEN_$number%/is;
    
    $number++;
}

foreach my $token_id ( 1 .. scalar(@tokens) ) {
    
    foreach my $value ( @{ $tokens[ $token_id - 1 ]->{values} } ) {
        
        my $output_text = $input_text;
        $output_text =~ s/%TOKEN_$token_id%/$value/is;
        
        while ( $output_text =~ m{%TOKEN_(\d+)}is ) {
            
            my $id = $1;
            $output_text =~ s/%TOKEN_$id%/$tokens[ $id - 1 ]->{values}
+->[0]/is;
        }
        
        print $output_text;
        
        #sleep 1;
    }

}

sleep 1;

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In reply to Find all string permutations by Gangabass

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