3v4l.org

run code in 300+ PHP versions simultaneously
<?php $words=['MVW','MWAH','MWAH','MYW','MW','MY9AH','MYQAH','MYQAH','MY9AH','MYQAH', 'MYQAH','MWAH','MYQAH','MYSWI','MYQAH','MYQAH','MW','MW','MW','MW']; echo implode( array_map(function(){ $occurrences=count_chars(implode(func_get_args()),1); arsort($occurrences); return chr(key($occurrences)); }, ...array_map('str_split',$words) ) );

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24.05 ms | 402 KiB | 5 Q