3v4l.org

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<?php function ackermann($n, $m) { if ($n == 0) { return 1 + $m; } if ($m == 0) { return ackermann($n - 1, 1); } return ackermann($n - 1, ackermann($n, $m - 1)); } echo ackermann(3, 3);
Output for 5.6.0 - 5.6.25, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
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preferences:
114.69 ms | 1674 KiB | 4 Q