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<?php function colorSequences($i1,$i2) { $m = strlen($i1); $n = strlen($i2); $at = str_split($i2); $count = 0; /*for($i=0;$i<$m;$i++){ if(count($i2) > 0){ if( in_array($i1[$i],$at) ){ $key = array_search($i1[$i],$at); unset($at[$key]); }else{ $count++; } }else{ $count++; } } return $count+(count($at))-$m;*/ return array_diff($i1, $i2); } print_r( colorSequences("xa","asdf")); ?>

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