#!/usr/bin/perl -l

# http://perlmonks.org/?node_id=1178025

use strict;
use warnings;

while(<DATA>)
  {
  my ($want, $in) = split;
  my $pat = $want =~ s/\B/?.?/gr . '?';
  #print $pat;
  my (@answers, %found);
  $in =~ /$pat(?{$found{$&}++ or $answers[length $&] .= "$& "})(*FAIL)/;
  print "$want in $in is ", @answers ? $answers[-1] : 'not found';
  }

__DATA__
ABC DFGABCKBG
ABC DFGAXBHCY
ABC DFGAXBHY