#include<iostream>
#include<string>
using namespace std;
int main(){
    string code;
    cin>>code;
    try{
        if(code.length()!=19)
        throw"Invalid";
        for(int i=0;i<19;i++){
            if(i==4||i==9||i==14){
                if(code[i]!='-')
                throw"Invalid";
            }
            else{
                if(!((code[i]<='A'&&*code[i]<='Z')||(code[i]>='0'&&code[i]<='9')))
                throw"Invalid";
            }
        }
        cout<<"valid";
    }
    catch(...){
        cout<<"Invalid";
    }
    return 0;
    }