51.从键盘上输入任意两个数和一个运算符（+、-、*、/），根据输入的运算符对两个数计算，并输出结果

​#include<iostream>
using namespace std;

int main()
{
int x,y;
char a;
cout<<"please input two numbers: "<<endl;
cin>>x>>y;
cout<<"please input an operational character:"<<endl;
cin>>a;

switch(a)//switch函数的参数还可用字符
{
case '+': cout<<"x+y="<<x+y;break;
case '-': cout<<"x-y="<<x-y;break;
case '*': cout<<"x*y="<<x*y;break;
case '/': cout<<"x/y="<<x/y;break;
default : break;
}

return 0;
}