Exams

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

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

        static void Main(string[] args)
        {
            int[] numbers = Console.ReadLine().Split(' ').Select(n => int.Parse(n)).ToArray();
            int result = mult(numbers[0], numbers[1]);
            Console.WriteLine(result);
            /* Ex.1
             int[] vaulchers = { 100, 20 };
            int days = int.Parse(Console.ReadLine());
            int money = days * 20;
            int i = 0;
            int count = 0;
            while (money != 0)
            {
                while (money - vaulchers[i] >= 0)
                {
                    money -= vaulchers[i];
                    count++;
                }
                i++;
            }
            Console.WriteLine(count);*/

        }
    }
}