Guys,
I'm wondering if there is a better/faster way to do it. Here is my current working code. 
#!/usr/bin/perl -w
use strict;

my $super = 'AAAAATT';
my $sub   =  'AT';     # Returns 1 (True)
#my $sub  =  'AAA';    # Returns 1 (True)
#my $sub  =  'GGG';    # Returns 0 (False)

print is_subst($super,$sub), "\n";

sub is_subst
{
    my  ($super,$sub)   = @_;
    my   $sup_len = length $super;
    my   $sub_len = length $sub;

    foreach  (my $i = 0; $i<$sup_len; $i++)
    {
       my $str = substr($super,$i,$sub_len);

       if ( $str eq $sub )
       {
           return 1;
           last;
       }
    }

    return 0;
}

[download]
Regards,
Edward

In reply to Testing if a string is a substring by monkfan

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