#include <iostream>
#include <cctype>
using namespace std;
int main(){
    char a,b;
    cin>>a>>b;
    if(!isdigit(a) || !isdigit(b)){
        cout<<"Invalid input";
    }
    else if(b==0){
        count<<"Division by zero is not allowed";
    }
    else{
        cout<<a/b;
    }
    return 0;
    
}