Hi,

I have a string and I would like to search for a substring with 0 or 1 mismatch. So, I went ahead and created all possible patterns (so that later I could regexp with foreach over all patterns):

$pattern{$opt_a} = 1;
for ($i=0; $i<length($opt_a); $i++) {
    $prop = $opt_a;
    substr($prop, $i, 1) = ".";
    $pattern{$prop}++;
}

[download]

I have 2 questions about this:

1) Is there an efficient way than this to search for mismatch?

2) If not, is there a possibility to obtain this set of patterns in a more efficient manner rather than using the typical for-loop structure ( I would suppose perl syntaxes enables us to write shorter than say C/C++)?

Thank you!

In reply to generating hash patterns for searching with one mismatch by cedance

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