using System;

public class Program

{

    public static void Main()

    {

        string input = Console.ReadLine();

        string[] inputarr = input.Split(' ');

        int i = Convert.ToInt32(inputarr[0]);

        int N = Convert.ToInt32(inputarr[1]);

        int o = 1;

        //minden körben hozzáadja k-t

        int k = N-1;

        for(int a = 1; a < i; a++)

            {

            o = o + k;

            k = k + N - 2;

            }

        int m = o / 1000000;

        o = o - (m * 1000000); 

        Console.WriteLine(o);

        Console.ReadLine();

    }

}