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run code in 500+ PHP versions simultaneously
<?php $ht = array(1 => 1, 2 => 2, 3 => 3, 4 => 9); $range = range(0,10); Unset($range[0]); // unset 0 since you want 1 as lowest $x = array_intersect_key(array_fill(1,max($ht), "x"), array_flip($ht)); $new = array_replace($range, $x); Echo Implode("", $new);
Output for 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 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
xxx45678x10

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81.38 ms | 1402 KiB | 4 Q