3v4l.org

run code in 300+ PHP versions simultaneously
<?php $array = [[6],[6],[6],[5,1],[3,3],[3,3],[3,2,1]]; $result = []; foreach ($array as $row) { $key = json_encode($row); $result[$key] = [$row, ($result[$key][1] ?? 0) + 1]; } echo json_encode(array_values($result));

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26.52 ms | 405 KiB | 5 Q