3v4l.org

run code in 300+ PHP versions simultaneously
<?php $array = array( 0 => "a,b", 1 => "c,d", 2 => "e,f", 3 => "g,h", ); $array[] = implode(",", array_splice($array, -2)); var_export($array);
Output for 7.4.0 - 7.4.33, 8.0.1 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
array ( 0 => 'a,b', 1 => 'c,d', 2 => 'e,f,g,h', )

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115.87 ms | 406 KiB | 5 Q