using System;

namespace _09.TopNumber
{
    class Program
    {
        static void Main(string[] args)
        {
            int num1 = int.Parse(Console.ReadLine());
            int num2 = int.Parse(Console.ReadLine());

            Factorial(num1, num2);
        }


        static void Factorial(int num1, int num2)
        {
            int num1res = 0;
            int num2res = 0;

            int counter1 = num1;
            int counter2 = num2;
            int resultOne = 0;
            int resultTwo = 0;
            for (int i = 0; i <= num1; i++)
            {
                counter1--;

                num1res = num1 * (counter1);
                resultOne += num1res;

            }
            for (int i = 0; i <= num2; i++)
            {
                counter2--;

                num2res = num2 * (num2);
                resultTwo += num2res;

            }
            Console.WriteLine(resultOne / resultTwo);
        }
    }
}