#include <bits/stdc++.h> using namespace std; int main () { double a,s; char d; cin>>a>>d>>s; if(d=='+') { cout<<a+s; } else if(d=='-') { cout<<a-s; } else if(d=='') { cout<<as; } else if(d=='/') { if(s==0) { cout<<"Divided by zero!"; } else { cout<<a/s; } } else { cout<<"Invalid operator!"; } return 0; } ****