题解 | #实现简单计算器功能#

#include <iostream>
#include <sstream>
#include <vector>
using namespace std;
void split_string(string& s, const char flag, vector<string>& res) {
    istringstream iss(s);
    string token;
    while (getline(iss, token, flag))
        res.push_back(token);
}
void computed(vector<string>& v) {
    string op = v[0];
    if (op == "add") cout << atoi(v[1].c_str()) + atoi(v[2].c_str()) << endl;
    else if (op == "sub") cout << atoi(v[1].c_str()) - atoi(v[2].c_str()) << endl;
    else if (op == "mul") cout << atoi(v[1].c_str()) * atoi(v[2].c_str()) << endl;
    else {
        if (v[2] == "0") cout << "Error" << endl;
        else cout << atoi(v[1].c_str()) / atoi(v[2].c_str()) << endl;
    }
}
int main() {

    char str[100] = { 0 };
    cin.getline(str, sizeof(str));

    // write your code here......
    vector<string> res;
    string s(str);
    split_string(s, ' ', res);
    computed(res);
    return 0;
}