Quick sorting (divide and conquer)

1   //  Quick sorting  2   3 # Include <iostream> 4 # Include <cstdlib> 5   Using   Namespace  STD;  6   7   Int Part ( Int S [], Int P,Int R) //  Put the number greater than s [p] to one side, and the number smaller than s [p] to one side.  8   {  9    Int X = S [p];  10    Int I = P + 1  ;  11    Int J = R;  12   While ( True  )  13   {  14     While (S [I] <X & I <= r) I ++ ;  15     While (S [J]> X & J> = 1 ) J -- ;  16     If (I> = J) 17      Break  ;  18     Int Temp = S [I];  19 S [I] = S [J];  20 S [J] = Temp;  21   }  22 S [p] = S [J];  23 S [J] = X; 24    Return  J;  25   }  26   27   28   Void Quicksort ( Int S [], Int P, Int  R)  29   {  30    If (P <R)  31   {  32     Int Q = Part (S, P, R );  33 Quicksort (S, P, Q- 1  );  34 Quicksort (S, q + 1  , R );  35   }  36   } 37   38   Int  Main ()  39   {  40    Int S [] = { 1 , 5 , 3 , 8 , 4 , 10 , 5  }; 41    Int P = 0  ;  42    Int R = Sizeof S/ Sizeof * S- 1  ;  43 Cout < "  Before sorting:  " < Endl;  44   For ( Int I = 0 ; I <= r; I ++ )  45 Cout <s [I] < "    "  ;  46 Cout < Endl;  47   Quicksort (S, P, R );  48 Cout < "  After sorting: " < Endl;  49    For (I = 0 ; I <= r; I ++ )  50 Cout <s [I] < "    "  ;  51 Cout < Endl;  52 }