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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"));
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 two two three two three four three three four four
preferences:
330.84 ms | 405 KiB | 415 Q