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<?php function permutation(array $arr) { while($ele=array_shift($arr)) { $x=$ele; echo $x."\n"; foreach($arr as $rest) { $x.=" $rest"; echo $x."\n"; } } } permutation(array("one","two","three","four","five"));
Output for 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
one one two one two three one two three four one two three four five two two three two three four two three four five three three four three four five four four five five

preferences:
308.99 ms | 405 KiB | 415 Q