for (my $i = 0; $i < $len; $i++) {
   $score += ((substr($ref_seq, $i, 1)) eq (substr($test_seq, $i, 1)));
}
return ($score / $len);

##</code><code>##

string1: "EKFCNSVVDLYSNLSKPFLDIVLYIFKLTSAIGAQGPA----SMMAYLVV"
string2: "ERFCRQLSSMASKLI-------ISPFTLVYYTYQCFQSTGWPVSIFGYFI"