in reply to Compare two variables

This will count the matching characters. 
my $orig = <DATA>;

my $i = 0;
while (<DATA>) {
    my $matches = $orig ^ $_;
    printf "Sequence %d has %d identities\n", $i++, $matches =~ tr/\0/
+/;    
}

__DATA__
ATCGGGACG 
TCGTCAGCG
ATGCGAAAA

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Prints: 
Sequence 0 has 2 identities
Sequence 1 has 4 identities

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Re^2: Compare two variables
by dmunoze (Initiate) on May 20, 2014 at 00:17 UTC

    Thanks for the answer, but I didn't understand the line with DATA. I mean, what exactly DATA contains?

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      Here's essentially the same thing without __DATA__: 

      c:\@Work\Perl\monks>perl -wMstrict -le
"my $seq = 'ATCGGGACG';
 my $n = 0;
 ;;
 for my $s (qw(TCGTCAGCG ATGCGAAAA TTTTTTTTT TATTTTTTT)) {
   print qq{\n'$seq' original};
   my $idents = (my $same = $s ^ $seq) =~ tr/\x00//;
   $same =~ tr/\x00-\xff/^ /;
   print qq{'$s' seq }, $n++;
   print qq{ $same  $idents identities};
   }
"

'ATCGGGACG' original
'TCGTCAGCG' seq 0
        ^^  2 identities

'ATCGGGACG' original
'ATGCGAAAA' seq 1
 ^^  ^ ^    4 identities

'ATCGGGACG' original
'TTTTTTTTT' seq 2
  ^         1 identities

'ATCGGGACG' original
'TATTTTTTT' seq 3
            0 identities

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