- <?php 
-   
-   
-   findMissing($list,1,100); 
-   
-   function findMissing($list, $min, $max) { 
-       return; 
-     } 
-   
-     $l = $r = []; 
-   
-     foreach($list as $number) { 
-       if($number < $pivot) { 
-         $l[] = $number; 
-       } 
-       else { 
-         $r[] = $number; 
-       } 
-     } 
-   
-     if(count($l) == $pivot - $min - 1) { 
-       // only 1 missing number use difference of sums 
-     } 
-     else if(count($l) < $pivot - $min) { 
-       // more than 1 missing number, recurse 
-       findMissing($l, $min, $pivot-1); 
-     } 
-   
-     if(count($r) == $max - $pivot - 1) { 
-       // only 1 missing number use difference of sums 
-     } else if(count($r) < $max - $pivot) { 
-       // mroe than 1 missing number recurse 
-       findMissing($r, $pivot+1, $max); 
-     } 
-   } 
				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