#include <stdio.h>
    swap(int * pi, int * pj)  {
      int temp;
	  temp = * pi;
	  * pi = * pj;
	  * pj = temp;
    }

    main()  {
	 int a,b;
	 int *pa, *pb;
	 printf("Please input a and b: \n");
	 scanf("%d  %d", &a, &b);
	 pa = &a;
	 pb = &b;
	 if(a<b)  swap(pa, pb);
	 printf("\n max=%d, min=%d \n", a, b);
         while(1);
    }