#include<iostream>
using namespace std;
int main()
{
    string a;
    int b,c;
    try
    {
        cin>>a;
        cin>>b;
        c=a.length()
        if(c<3)
        {
            throw"Invalid username";
        }
        if(b<18 || b>100)
        {
            throw"Invalid age";
        }
        cout<<"Registration successful";
        
    }
    catch(const char*msg)
    {
        cout<<msg;
    }
}