Exam Preparation

using System;
using System.Linq;

namespace Exam01
{
    class Program
    {
        public static int mult(int m, int n)
        {
            if (n == 1)
            {
                return m;
            }
            return mult(m, n - 1) + m;
        }

        public static int mult2(int m, int n)
        {
            if (n == 1)
            {
                return m;
            }
            else if (n > 1)
            {
                return mult2(m, n - 1) + m;
            }
            return mult2(m, n + 1) - m;
        }

        static void Main(string[] args)
        {
            // Exam 01:
            /*int days = int.Parse(Console.ReadLine());
            int[] cards = { 100, 20 };
            int money = days * 20;
            int count = 0;
            for (int i = 0; i < cards.Length; i++)
            {
                while (money - cards[i] >= 0)
                {
                    money -= cards[i];
                    count++;
                }
                if (money == 0)
                {
                    break;
                }
            }
            Console.WriteLine(count);*/

            // Exam02:
            int[] numbers = Console.ReadLine().Split(' ').Select(n => int.Parse(n)).ToArray();
            int result = mult2(numbers[0], numbers[1]);
            Console.WriteLine(result);

        }
    }
}