using System;
					
public class Program
{
	public static void Main()
	{ 
	//Máquina de Café
		//Variáveis- Coffee Size
		
		int CoffeeSize;
		do{
		Console.WriteLine("Welcome to C# Coffee Machine");
		Console.WriteLine("Please select one of the options:");
		Console.WriteLine("1=Small cofee");
		Console.WriteLine("2=medium cofee");
		Console.WriteLine("3=large cofee");
		
		CoffeeSize=int.Parse(Console.ReadLine());
			
		}while(CoffeeSize<0||CoffeeSize>3);
		
		
		// Coffee cost
		
		
		if(CoffeeSize==1){
			Console.WriteLine("Please insert 25 cents");
		}else {
		}
		
		if(CoffeeSize==2){
			Console.WriteLine("Please insert 50 cents");
		}else {
		}
		
		if(CoffeeSize==3){
			Console.WriteLine("Please insert 60 cents");
		}else {
		}	

		
		
	//despedir
		int coffeecost;
		do{
		
		coffeecost=int.Parse(Console.ReadLine());
		
		if ((CoffeeSize == 1 && coffeecost==25)||(CoffeeSize == 2 && coffeecost==50)||(CoffeeSize == 3 && coffeecost==60)){
		Console.WriteLine("Thank you! See you next time.");
			
		}else {
		Console.WriteLine("Please insert the exact value of cost");
		}
		
		}while(!((CoffeeSize == 1 && coffeecost==25)||(CoffeeSize == 2 && coffeecost==50)||(CoffeeSize == 3 && coffeecost==60)));
		
		
	}
}