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<?php $mainArr = [ [125 => 'B', 127 => 'A', 178 => 'Z', 78 => 'G'], [111 => 'X', 127 => 'K', 108 => 'J', 708 => 'P'], [125 => 'L', 127 => 'M', 178 => 'Q', 78 => 'A'], ]; array_walk($mainArr, fn(&$subarray) => asort($subarray)); var_export($mainArr);

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