#!/usr/bin/perl

# http://perlmonks.org/?node_id=1144405

use Algorithm::Diff qw(traverse_sequences);
use strict;
use warnings;

my $S=" MSATPLTQEQKKA";
my $T=" MNATLTQQTKA";

my @from = split //, shift // $S;
my @to = split //, shift // $T;

my $top = '';
my $bottom = '';

traverse_sequences( \@from, \@to,
  {
  MATCH     => sub {$top .= $from[shift()]; $bottom .= $to[pop()]},
  DISCARD_A => sub {$top .= $from[shift()]; $bottom .= ' '},
  DISCARD_B => sub {$top .= ' '; $bottom .= $to[pop()]},
  } );
print "$top\n$bottom\n";