C语言用函数指针实现一个特别的计算器

int add(int x, int y)
{
	return x + y;
}
int sub(int x, int y)
{
	return x - y;
}
int mul(int x,int y)
{
	return x * y;
}
int exc(int x, int y)
{
	return x / y;
}
void func(int *(pf)(int, int y))
{
	int x = 0;
	int y = 0;
	printf("请输入两个数:");
	scanf("%d%d", &x, &y);
	int ret = pf(x, y);
	printf("结果为:%d\n", ret);
}

#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
void menu() 
{
	printf("|-------------------|\n");
	printf("|-------1.加--------|\n");
	printf("|-------2.减--------|\n");
	printf("|-------3.乘--------|\n");
	printf("|-------4.除--------|\n");
	printf("|-------0.退出------|\n");
	printf("|-------------------|\n");
}
int add(int x, int y)
{
	return x + y;
}
int sub(int x, int y)
{
	return x - y;
}
int mul(int x,int y)
{
	return x * y;
}
int exc(int x, int y)
{
	return x / y;
}
void func(int *(pf)(int, int y))
{
	int x = 0;
	int y = 0;
	printf("请输入两个数:");
	scanf("%d%d", &x, &y);
	int ret = pf(x, y);
	printf("结果为:%d\n", ret);
}
int main()
{
	int n = 0;
	int flag = 1;
	while (flag)
	{
		menu();
		printf("请选择你想要的运算:");
		scanf("%d", &n);
		switch (n)
		{
		case 1:
			func(add);
			break;
		case 2:
			func(sub);
			break;
		case 3:
			func(mul);
			break;
		case 4:
			func(exc);
			break;
		case 0:
			flag = 0;
			break;
		default:
			printf("选择错误,请重新选择!\n");
			break;
		}
	}
	return 0;
}