#include<iostream>
#include<regex>
using namespace std;

int main(){
    string code;
    cin>>a;
    
   regex pattern("^[A-Z0-9]  {4} - [4-Z0-9]{4} -[A-Z0-9]{4}$");
   
   if(regex_match(a,pattern)){
       cout<<"Invalid";
       
   }
   else{
       cout<<"Valid";
       
   }
   return 0;
}