#include<bits/stdc++.h> using namespace std; int main(){ int a,b; char c; cin>>a>>b>>c; if (c=='+') {cout<<(a+b);} else if (c=='-') {cout<<a-b; } else if (c=='') {cout<<ab; } else if (c=='/') {if (b==0) {cout<<"Divided by zero!";} else {cout<<a/b; }} else {cout<<"Invalid operator!"; } return 0; } //自己换行