using System;

public class Program

{

    public static void Main()

    {

        int age = Convert.ToInt32(Console.ReadLine());

        if(RangeCheck(age,16,19)) Console.WriteLine("Age Valid");

else Console.WriteLine("Age Invalid");

​

    }

    public static bool RangeCheck (int age, int lower, int upper)

{

if(age>=lower && age<=upper ) return true;

    return false;

}

​

}