#include <iostream>
using namespace std;

class Calculator{
    public:
    int calculate(int a,int b,int t){
        if(t==1)return a+b;
        if(t==2)return a-b;
        if(t==3)return a*b;
        if(t==4) {
            if(b==0){
                cout<<"Division by zero";
                exit(0);
            }
            return a/b;
    }
    return 0;
}
double calculate(double a, double b, double t){
    if(t==1)return a+b;
        if(t==2)return a-b;
        if(t==3)return a*b;
        if(t==4) {
            if(b==0.0){
                cout<<"Division by zero";
                exit(0);
            }
            return a/b;
    }
    return 0;
}
};
int main(){
    int t;
    cin>>t;
    
    if(t<=0) {
        cout<<"Invalid input";
        return 0;
    }
    double a, b;
    cin>>a>>b;
    
    Calculator calc;
    
    if (a==(int)a && b==(int)b)
        cout<<calc.calculate((int)a,(int)b, t);
    else
        cout << calc.calculate(a, b, t);
    }
    return 0;
}