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<?php $stack = array("twice", "twice", "once", "another once"); print_r(array_filter(array_map((function ($v) { return $v > 1 ? $v : 0; }), array_count_values($stack))));
Output for 5.6.38 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.31, 8.3.0 - 8.3.31, 8.4.1 - 8.4.22, 8.5.0 - 8.5.7
Array ( [twice] => 2 )
preferences:
87.98 ms | 1793 KiB | 4 Q