Ah, never mind, I found this solution:
while($string=~/(M+)/g)
{
    ($start, $end) = ($-[0], $+[0]);
    print $start."\t".$end."\n";
}

[download]

Thanks

In reply to Re: how do you use the index function on this example? by Anonymous Monk
in thread how do you use the index function on this example? by Anonymous Monk

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