3v4l.org

run code in 300+ PHP versions simultaneously
<?php function computeCombination(array $source,$picks,$startIndex=0,array $pad=array()) { if($picks<=0) { return $pad; } elseif($picks>=count($source)-$startIndex) { return array(array_merge($pad,array_slice($source,$startIndex))); } $result=array(); foreach(range($startIndex,count($source)-$picks) as $subStartIndex) { $subPad=$pad; $subPad[]=$source[$subStartIndex]; if(empty($pad))// to make the output look nice { $result=array_merge($result,computeCombination($source,$picks-1,$subStartIndex+1,$subPad)); } else { $result=array_merge($result,array(computeCombination($source,$picks-1,$subStartIndex+1,$subPad))); } } return $result; } print_r(computeCombination(array(1,2,3,4,5),2));
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 - 7.1.30, 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 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Array ( [0] => Array ( [0] => 1 [1] => 2 ) [1] => Array ( [0] => 1 [1] => 3 ) [2] => Array ( [0] => 1 [1] => 4 ) [3] => Array ( [0] => 1 [1] => 5 ) [4] => Array ( [0] => 2 [1] => 3 ) [5] => Array ( [0] => 2 [1] => 4 ) [6] => Array ( [0] => 2 [1] => 5 ) [7] => Array ( [0] => 3 [1] => 4 ) [8] => Array ( [0] => 3 [1] => 5 ) [9] => Array ( [0] => 4 [1] => 5 ) )
preferences:
270.68 ms | 406 KiB | 390 Q