3v4l.org

run code in 300+ PHP versions simultaneously
<?php $input = [ ['01','03','02','15'], ['05','04','06','10'], ['07','09','08','11'], ['12','14','13','16'], ]; var_export( implode( '|', array_map( fn(...$column) => implode(',', $column), ...$input ) ) );
Output for 7.4.0 - 7.4.33, 8.0.1 - 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
'01,05,07,12|03,04,09,14|02,06,08,13|15,10,11,16'

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84.4 ms | 1248 KiB | 4 Q