简单计算器

贴一个代码框架，记住

#include <iostream>
#include <string>
#include <cstring>
#include <map>
#include <cstdio>

int main() {
    string s;
    while (getline(cin, s)) {
       
        s += '\0';

        for (int i = 0; i < s.size(); i++) {
            if (isdigit(s[i])) {
               
            } else if (s[i] == ' ' || s[i] == '\0') {
                
            } else { // 处理运算符
                // 处理所有更高或同优先级的运算符
                while (!ops.empty() && priority[ops.top()] >= priority[s[i]]) {
                    
                }
                ops.push(s[i]);
            }
        }

        // 处理剩余运算符
        while (!ops.empty()) {
           
        }

        printf("%.2f\n", nums.top());//输出规则
    }
    
}