逆波兰表达式（栈，递归）

#include<cstdio>
#include<iostream>
#include<windows.h>

double Calculation() 
{
    char a[10];
    scanf("%s",a);
    switch (a[0])
    {
        case ‘+‘:
        return Calculation()+Calculation();
        case ‘-‘:
        return Calculation()-Calculation();
        case ‘*‘:
        return Calculation()*Calculation();
        case ‘/‘:
        return Calculation()/Calculation();
        default:
        return atof(a);
    }
}

int main() 
{
    double ans;
    ans =Calculation();
    printf("%f\n",ans);
    return 0;
}