#!/usr/bin/perl
use strict;
use warnings;
use Inline C =>;

my $file = $ARGV[0] || 'phase1.data';
open(my $fh, '<', $file) or die "Unable to open '$file' for reading: $!";

my @word;
while (<$fh>) {
    chomp;
    my ($nform, $word) = split /\t/;
    push @word, $word;
}

$file = $ARGV[1] || 'phase3.data';
open($fh, '<', $file) or die "Unable to open '$file' for reading: $!";
while (<$fh>) {
    my ($nform, $str1, $str2, $str3) = split /\t/;
    for (@word) {
        if (! diff('abcdefghijklmnopqrstuvwxyz', $_ . $nform)) {
            print "abcdefghijklmnopqrstuvwxyz\t$_\t$str1\t$str2\t$str3";
            exit;
        }
    }
}
print "No Cigar\n";

__END__
__C__

SV *diff(char *str1, char *str2) {
    /* Actual code has 256 0s - truncated for post */
    char exists[256] = {};
    SV *ret_sv = newSVpvn("",0);
    
    /* identify all chars present in str2 */
    while (*str2) {
        exists[(U8)*str2++] = 1;
    }

    /* Determine chars in str1 not in str2 */
    for ( ; *str1 ; str1++ ) 
        if (! exists[(U8)*str1]) 
            sv_catpvn(ret_sv,str1,1);
    
    return ret_sv;
}