public class Ldelem
{
	public static void Main() {
		new Ldelem();
	}
	
	public Ldelem()
	{
		int[] a = new int[] {1, 2, 3, 4};
		if (a[3] == 4)
			Console.WriteLine("yup");
		else
			Console.WriteLine("nope");
		a[3] = 5;
		if (a[3] == 5)
			Console.WriteLine("yup");
		else
			Console.WriteLine("nope");
	}
}