But this routine sets up an infinite loop as far as I can tell. When I added a quick print "$_[0],$_[1]" to the beginning of the sub, the output led me to believe the problem here is the algorithm itself, not the technique used to save stack space. Am I missing something?

In reply to (ichimunki) Re x 4: Ackerman vs. Perl : KO in 3 rounds by ichimunki
in thread Ackerman vs. Perl : KO in 3 rounds by John M. Dlugosz

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