#!/usr/bin/perl
my $tag = uc(shift(@ARGV));
my $newLength = shift(@ARGV);

$tag =~ /G*(.*)/;
$tag2 = &translateIUPAC($1);

#print "$tag2\n";

while($line = <STDIN>){
    chomp($line);

    if($line =~ />(.*)/){
	print "$line\n";
    }
    else{
	$line =~ /$tag2(.*)/; 	
	$parse = $1;
	$truncate = substr($parse, 0, $newLength);

	print "$truncate\n";
    }
}

sub translateIUPAC()
{
  my ($seq) = @_;

  $seq=~s/W/\[AT\]/g;
  $seq=~s/B/\[CGT\]/g;
  $seq=~s/S/\[GC\]/g;  
  $seq=~s/N/\[ACTG\]/g;
  $seq=~s/Y/\[CT\]/g;
  $seq=~s/R/\[AG\]/g;
  $seq=~s/D/\[AGT\]/g;
  $seq=~s/H/\[ACT\]/g;
  $seq=~s/M/\[AC\]/g;
  $seq=~s/K/\[GT\]/g;
  $seq=~s/V/\[ACG\]/g;
  return $seq;
}