#include
using namespace std;
int main(){
char c;
int a,b;
cin>>c;
cin>>a>>b;
while(c!=‘X’ || c!=‘x’){
if(c==’+’){
cout<<a+b<<endl;
}
else if(c==’-’){
cout<<a-b<<endl;
}
else if(c==’’){
cout<<ab<<endl;
}
else if(c==’/’){
cout<<a/b<<endl;
}
else{
cout<<“Invalid operation. Try again.”;
}
cin>>c;
if(c==‘x’ || c==‘X’){
break;
}
cin>>a>>b;
}
return 0;
}