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<?php $mode[1] = [1, 2, 5, 6]; $mode[0] = [3, 4, 7, 8]; var_export( array_reduce( array_keys($mode), fn($result, $k) => $result += array_fill_keys($mode[$k], $k), [] ) );
Output for 8.0.1 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.27, 8.4.1 - 8.4.14
array ( 1 => 1, 2 => 1, 5 => 1, 6 => 1, 3 => 0, 4 => 0, 7 => 0, 8 => 0, )
preferences:
101.29 ms | 406 KiB | 5 Q