C++ :

#include <bits/stdc++.h>
using namespace std;  

int main() {  
    int o,o2;  
    string ol;  
    cin >> o >> o2 >> ol;  
    if (ol != "+" && ol != "-" && ol != "*" && ol != "/") {  
        cout << "Invalid operator!" << endl;  
        return 0;  
    }  
    if (ol == "+") {  
        cout << o + o2 << endl;  
    } else if (ol == "-") {  
        cout << o - o2 << endl;  
    } else if (ol == "*") {  
        cout << o * o2 << endl;  
    } else if (ol == "/") {  
        if (o2 == 0) {  
            cout << "Divided by zero!" << endl;  
        } else {  
            cout << o / o2 << endl;
        }  
    }  

    return 0;  
}