using System;
public class Program
{
public static void Main()
Console.Write("n = ");
int n = int.Parse(Console.ReadLine());
Console.Write("m = ");
int m = int.Parse(Console.ReadLine());
int num = n;
long product = 1;
do
product *= num; num++;
}
while (num <= m);
Console.WriteLine("product[n...] = " + product);