3v4l.org

run code in 300+ PHP versions simultaneously
<?php $arr = array(12,43,66,21,56,43,43,78,78,100,43,43,43,21); foreach($arr as $key=>$item){ if(array_count_values($arr)[$item] > 1){ echo "Found Matched value : ".$item."\n"; } }

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41.7 ms | 402 KiB | 5 Q