3v4l.org

run code in 300+ PHP versions simultaneously
<?php $arr =Array ( 0 => Array ( 0 => 8147, 1 => 3 ), 1 => Array ( 0 => 8204, 1 => 20 ) ); $match_array = array_column($arr,0); $str = implode(",",$match_array); echo $str;
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.27, 8.4.1 - 8.4.14
8147,8204
preferences:
152.83 ms | 408 KiB | 5 Q