import java.util.Scanner;


public class Christian
{
    public static void main(String[] args)
    {
        Scanner input = new Scanner(System.in);

        System.out.print("Enter a number x to compute e^x: ");
        int x = input.nextInt();
        System.out.print("Enter a Precision: ");
        double precision = input.nextDouble();

        double sum = 0, result = 0, difference = 0, n = 0;
        do
        {
            double numerator = Math.pow(x, n);
            double denominator = factorial(n);

            result = numerator/denominator;
            sum += result;
            difference = sum - result;
            ++n;

        }while(difference > precision );
        System.out.print(result);
    }

    public static double factorial(double n)
    {
        int ret = 1;
            for (double i = 1.0; i <= n; ++i) ret *= i;
            return ret;
    }
}