Question

C++如何输入一个数学符号并储存？

要遍一个模拟袖珍计算器，要求输入两个数和一个操作符用switch语句进行计算，我的代码如下，总是报错illegal break，求高人指点。
double x,y,ans;
char z;
cout<<"input number 1 op number 2"<<endl;
cin>>x>>y>>z;
switch (z)
case '+':ans=x+y;
break;
case '-':ans=x-y;
break;
case '*':ans=x*y;
break;
case '/':ans=x/y;
break;
default:cout<<"can't do it"<<endl;
cout<<x<<z<<y<<"="<<ans<<endl;

Answer 1

switch (z)
{// switch这里加个大括号
case '+':ans=x+y;
break;
case '-':ans=x-y;
break;
case '*':ans=x*y;
break;
case '/':ans=x/y;
break;
default:cout<<"can't do it"<<endl;
}// switch这里加个大括号

Answer 2

改成这样
double x,y,ans;
char z;
cout<<"input number 1 op number 2"<<endl;
cin>>x>>y>>z;
switch (z)
{
case '+':ans=x+y;break;
case '-':ans=x-y;break;
case '*':ans=x*y;break;
case '/':ans=x/y;break;
default:
cout<<"can't do it"<<endl;
break;
}
cout<<x<<z<<y<<"="<<ans<<endl;