3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a1 = [ ['127.0.0.1',11211], ['127.0.0.2',11211], ['127.0.0.4',11211], ]; $a2 = [ ['127.0.0.1',11211], ['127.0.0.2',11211], ['127.0.0.3',11211], ['127.0.0.4',11211], ]; print_r( array_udiff( $a1, $a2, function($a,$b){ return $a[0] === $b[0]; } ) );

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