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run code in 300+ PHP versions simultaneously
<?php $s = "12345"; $res = []; if (preg_match_all('~(?=((\d)\d?))~', $s, $m, PREG_SET_ORDER)) { $single = []; $double = []; foreach ($m as $v) { if ($v[1] != $v[2]) { array_push($single, $v[2]); array_push($double, $v[1]); } else { array_push($single, $v[1]); } } $res = array_merge($single, $double); print_r( $res ); }
Output for 7.4.0 - 7.4.33, 8.0.1 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Array ( [0] => 1 [1] => 2 [2] => 3 [3] => 4 [4] => 5 [5] => 12 [6] => 23 [7] => 34 [8] => 45 )
preferences:
121.15 ms | 402 KiB | 121 Q