#! perl -slw
use strict;

my $bigstring="MNRIYSLRYSAVARGFIAVSEFARKCVHKSVRRLCFPVLLLIPVLFSAGSLAGTVNNELGYQLFRDFAENKGMFRPGATNIAIYNKQGEFVGTLDKAAMPDFSAVDSEIGVATLINPQYIASVKHNGGYTNVSFGDGENRYNIVDRNNAPSLDFHAPRLDKLVTEVAPTAVTAQGAVAGAYLDKERYPVFYRLGSGTQYIKDSNGQLTKMGGAYSWLTGGTVGSLSSYQNGEMISTSSGLVFDYKLNGAMPIYGEAGDSGSPLFAFDTVQNKWVLVGVLTAGNGAGGRGNNWAVIPLDFIGQKFNEDNDAPVTFRTSEGGALEWSFNSSTGAGALTQGTTTYAMHGQQGNDLNAGKNLIFQGQNGQINLKDSVSQGAGSLTFRDNYTVTTSNGSTWTGAGIVVDNGVSVNWQVNGVKGDNLHKIGEGTLTVQGTGINEGGLKVGDGKVVLNQQADNKGQVQAFSSVNIASGRPTVVLTDERQVNPDTVSWGYRGGTLDVNGNSLTFHQLKAADYGAVLANNVDKRATITLDYALRADKVALNGWSESGKGTAGNLYKYNNPYTNTTDYFILKQSTYGYFPTDQSSNATWEFVGHSQGDAQKLVADRFNTAGYLFHGQLKGNLNVDNRLPEGVTGALVMDGAADISGTFTQENGRLTLQGHPVIHAYNTQSVADKLAASGDHSVLTQPTSFSQEDWENRSFTFDRLSLKNTDFGLGRNATLNTTIQADNSSVTLGDSRVFIDKNDGQGTAFTLEEGTSVATKDADKSVFNGTVNLDNQSVLNINDIFNGGIQANNSTVNISSDSAVLGNSTLTSTALNLNKGANALASQSFVSDGPVNISDATLSLNSRPDEVSHTLLPVYDYAGSWNLKGDDARLNVGPYSMLSGNINVQDKGTVTLGGEGELSPDLTLQNQMLYSLFNGYRNIWSGSLNAPDATVSMTDTQWSMNGNSTAGNMKLNRTIVGFNGGTSPFTTLTTDNLDAVQSAFVMRTDLNKADKLVINKSATGHDNSIWVNFLKKPSNKDTLDIPLVSAPEATADNLFRASTRVVGFSDVTPILSVRKEDGKKEWVLDGYQVARNDGQGKAAATFMHISYNNFITEVNNLNKRMGDLRDINGEAGTWVRLLNGSGSADGGFTDHYTLLQMGADRKHELGSMDLFTGVMATYTDTDASADLYSGKTKSWGGGFYASGLFRSGAYFDVIAKYIHNENKYDLNFAGAGKQNFRSHSLYAGAEVGYRYHLTDTTFVEPQAELVWGRLQGQTFNWNDSGMDVSMRRNSVNPLVGRTGVVSGKTFSGKDWSLTARAGLHYEFDLTDSADVHLKDAAGEHQINGRKDSRMLYGVGLNARFGDNTRLGLEVERSAFGKYNTDDAINANIRYSF";
my $smallstring="GTMARNDGQGKAAATFMHISYNNFITEVDNLNKRMGDLRDINGEAGTWVRLLNGSGSADGGFTDHYTLLQMGADRKHELGSMDLFTGVMATYTDTDASADLYSGKTKSWGGGFYASGLFRSGAYFDVIAKYIHNENKYDLNFAGAGKQNFRSHSLYAGAEVGYRYHLTDTTFVEPQAELVWGRLQGQTFNWNDSGMDVSMRRNSVNPLVGRTGVVSGKTFSGKDWSLTARAGLHYEFDLTDSADVHLKDAAGEHQINGRKDSRMLYGVGLNARFGDNTRLGLEVERSAFGKYNTDDAINANIRYSFLE";
my $lenBig = length $bigstring;
my $lenSmall = length $smallstring;
my $threshold = 0.9;

for my $o ( 0 .. $lenBig - $threshold*$lenSmall ) {
    my $masked = substr( $bigstring, $o, $lenSmall ) ^ $smallstring;
    my $matched = $masked =~ tr[\0][];
    if( ( $matched / $lenSmall ) > $threshold ) {
        $masked =~ tr[\1-\255][ ];
        $masked =~ tr[\0][*];
        printf "%.2f%% match at offset %u\n", $matched / $lenSmall * 100, $o;
        print substr $bigstring, $o, $lenSmall;
        print $smallstring;
        print $masked;
    }
}