using System

class Program
{
	static int Fact(int n)
	{
		int sum = 1;	
		for(int i = 2;i<=n;i++)
		{
			sum *= i;	
		}
		return sum;
	}

	static double Gipcos(double x, double e)
	{
		double sum = 1;
		int n = 2;
		while(Math.Pow(x,n)/Fact(n) > e)
		{
			sum += Math.Pow(x,n)/Fact(n);
			n+=2;
		}
		return sum;
	}	

	static void main()
	{
		Console.Write("x = ");
		double x = double.Parse(Console.ReadLine());	
		Console.Write("e = ");
		double e = double.Parse(Console.ReadLine());		
		Console.WriteLine("Cos x = " + Gipcos(x,e));
		Console.WriteLine("Cos x = " + Math.Ccos(x));
	}
}