C# 随机红包算法

 static void Main(string[] args)
         {
             double totalAmount = ;
             int num = ;
             double minAmount = 0.01;
             Random r = new Random();
             for (int i = ; i < num; i++)
             {
                 double safeAmount = (totalAmount - (num - i) * minAmount) / (num - i);
                 //double money = new Random().Next(Convert.ToInt32(minAmount * 100), Convert.ToInt32(safeAmount * 100)) / 100;
                 double money = NextDouble(r, minAmount * , safeAmount * ) / ;
                 money = Math.Round(money, , MidpointRounding.AwayFromZero);
                 totalAmount=totalAmount-money;
                 totalAmount = Math.Round(totalAmount, , MidpointRounding.AwayFromZero);
                 Console.WriteLine("第" + i + "个红包：" + money + " 元，余额：" + totalAmount + " 元");
             }
             Console.WriteLine("第" + num + "个红包：" + totalAmount + " 元，余额：0 元");

             Console.ReadKey();
         }

         /// <summary>
         /// 生成设置范围内的Double的随机数
         /// eg:_random.NextDouble(1.5, 2.5)
         /// </summary>
         /// <param name="random">Random</param>
         /// <param name="miniDouble">生成随机数的最大值</param>
         /// <param name="maxiDouble">生成随机数的最小值</param>
         /// <returns>当Random等于NULL的时候返回0;</returns>
         protected static double NextDouble(Random random, double miniDouble, double maxiDouble)
         {
             if (random != null)
             {
                 return random.NextDouble() * (maxiDouble - miniDouble) + miniDouble;
             }
             else
             {
                 return 0.0d;
             }
         }