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));
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 - 8.3.26, 8.4.1 - 8.4.13
[[[6],3],[[5,1],1],[[3,3],2],[[3,2,1],1]]

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