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

int main(){
    string username;
    int age;
    
    getline(cin, username);
    cin >> age;
    
    try{
        if(username.length() < 3){
            throw "Invalid username";
        }
        if(age < 18 || age > 100){
            throw "Invalid age";
        }
        
        cout<<"Registration successful";
    }
    catch(const chat* msg){
        cout<<msg;
    }
    return 0;
}