#!/usr/bin/perl -w

use strict; #always

sub myencode {
  my ($sentence,$encodehash)=@_ or die "not enough parameters for encode:@_";
  foreach my $key (keys %$encodehash) {
    $sentence =~ s!$key!$$encodehash{$key}!g;
  }
  return $sentence;
}
my %encoding=("A"=>"D","B"=>"E","C"=>"F");
print myencode("ABC",\%encoding);