#include<iostream>
#include<regex>
using namespace std;
int main()
{
    string code;
    cin>>code;
    try{
        regex pattarn("^[A-Z0-9]{4}-[A-Z0-9]{4}-[A-Z0-9]{4}$")
        IF (regex_match(code,pattern)){
            cout<<"Valid";
        }
        else{
            throw invalid_argument("Invalid format");
        }
    }
    catch(...){
        cout<<"Invalid";
    }
    return 0;
}