函式指標
    // ConsoleApplication2.cpp : 定義控制檯應用程式的入口點。
    //
    
    #include "stdafx.h"
    #include "stdio.h"
    #pragma warning(disable:4996)
    void main()
    {
    	int max(int, int);
    	int min(int, int);
    	int add(int, int);
    	int sub(int, int, int(*p)(int, int));
    	int(*p_max)(int, int);
    	int(*p_min)(int, int);
    	int(*p_add)(int, int);
    	int c;
    	int d;
    	int e;
    
    	int in1, in2;
    	p_max = max;
    	p_min = min;
    	p_add = add;
    
    
    	printf("Give two int num:\n");
    	scanf("%d %d", &in1, &in2);
    	c = sub(in1, in2, p_max);
    	printf("%d and %d max is:%d\n", in1, in2, c);
    	d = sub(in1, in2, p_min);
    	printf("%d and %d min is:%d\n", in1, in2, d);
    	e = sub(in1, in2, p_add);
    	printf("%d and %d add is:%d\n", in1, in2, e);
    }
    
    int max(int x, int y)
    {
    	if (x>y)
    		return x;
    	else
    		return y;
    }
    int min(int x, int y)
    {
    	if (x < y)
    		return x;
    	else
    		return y;
    }
    int add(int x, int y)
    {
    	return x + y;
    }
    int sub(int x, int y, int(*p)(int, int))
    {
    	return p(x, y);
    }