using System;

class TossACoin
{
	public static void Main()
	{
		int face; //Head: face==1. Tail: face==0
		int num_tosses = 0;
		Random random = new Random(); //A generator to create random numbers
		
		do
		{
			int random_int = random.Next(); //Generate a random integer

			face = random_int % 2;						
			num_tosses++;

		} while (face == 0); //continue to toss if a tail is obtained

		Console.WriteLine("Tossed {0} times when a head is obtained", num_tosses);
	}
}