3v4l.org

run code in 300+ PHP versions simultaneously
<?php $array = array( 3 => 15, 30 => 1, 1 => 1 ); $string = implode( array_map( function($v, $k) { return "$k:$v;"; }, $array, array_keys($array) ) ); echo $string;

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42.89 ms | 402 KiB | 5 Q