3v4l.org

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);

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