利用随机数 求两数相减不退位

static void Main(string[] args)
        {
            while (true)
            {

                int a, b, c,m,n;
                Random r = new Random();  //主要的就是三位数的百分位最大不会同时取到四位数的百分位，也就是说c永远小于b;
                a = r.Next(1,10);
                b=r.Next(2, 10);
                c = r.Next(1,b);
                m = 1000 * a + 100 * b;
                n = 100 * c;
                Console.WriteLine(m+"-"+n+"的结果为"+(m-n));

                Console.ReadLine();
            }
        }