#include"stdio.h"
int add(int a,int b)
{
    return (a+b);
}
int sub(int a,int b)
{
    return (a-b);
}
int mul(int a,int b)
{
    return a*b;
}
int div(int a,int b)
{
    if(b==0)
    { 
        printf("Divide 0 Error!\n");
        return -1;
    }
    return a/b;
}
void GetOper(int select,int a,int b,int (*p)())
{
    switch(select)
    { 
    case 1: p=add;
	    break;
    case 2: p=sub;
	    break;
    case 3: p=mul;
	    break;
    case 4: p=div;
	    break;
    default:  printf("Error Selection\n");
	    return;
    }
    printf("The result is %d\n",(*p)(a,b));
}
main()
{ 
    int select,a,b;
    int (*p)();
    clrscr();
    printf("Please input two integer number:\n");
    scanf("%d%d",&a,&b);
    printf("Please select an operation:\n");
    printf("     1.Add     2.Sub     3.Multipl     4.Divide\n");
    scanf("%d",&select);
    GetOper(select,a,b,p);
    getch();
}