Re: Pattern Searching

[grondilu]

Common pattern in different strings? Using KMP?

I think I solved the corresponding problem on rosalind.info. Here is my solution:

#!/usr/bin/perl
use strict;
use warnings;

sub kmp {
    my @T = (-1, 0);
    my ($pos, $cnd) = (2, 0);
    while ( $pos <= @_ ) {
        if ($_[$pos-1] eq $_[$cnd]) { $T[$pos++] = ++$cnd }
        elsif ($cnd > 0) { $cnd = $T[$cnd] // 0 }
        else { $T[$pos++] = 0 }
    }
    shift @T;
    return @T;
}

use List::Util qw(max min);
sub lcs {
    my @first = split //, my $first = shift;
    my $n = @first;
    my @string = map [ split //, $_ ], @_;
    my ($pos, $length) = (0, 0);
    SUFFIX: for my $p ( 0 .. $n - 1 ) {
        shift @first if $p;
        my @max;
        for (@string) {
            my @kmp = kmp @first, '$', @$_;
            my $max = max @kmp;
            next SUFFIX if $max < $length;
            push @max, $max;
        }
        if ((my $min = min @max) > $length) {
            ($pos, $length) = ($p, $min);
        }
    }
    return substr $first, $pos, $length;
}

open my $f, '< rosalind_lcs.txt' or die "could not open: $!";
say lcs <$f>;

Hope this will help

[Anonymous Monk]

hey Monkeys I need more support. I am trying this from 10 hours. I have to show results to my supervisor. I try my level best and still trying. The problem is in printing the @loc array in 2nd iteration. I try my level best to debug this. What I understand is that in 2nd iteration the condition is true for only one time where as the @loc array values shows that the condition should be true for all values.I tried to fix it but all results into nothing. Please help me.

[aseee]

sorry the word is PerlMonks not monkeys. Extremely sorry.

[Anonymous Monk]

Where do you work? Who is your supervisor?