my($i,$j,$k,$l) = split (//,$num_string);

I haven't done any Benchmark-ing (and won't), but unpack might be faster than split:
    my($i,$j,$k,$l) = unpack '(a)4', $num_string;

Give a man a fish:  <%-{-{-{-<

In reply to Re^2: looping efficiency by AnomalousMonk
in thread looping efficiency by Anonymous Monk

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