趣味问题1（C#）

 /*

15个教徒和非教徒在海上遇险，必须将一半的人投入大海，其余的人才能幸免于难，于是想了一个办法：30个人围城一圈，从第一个人开始依次报数，

每数到第九个人就把他丢入海中，如此循环进行直到仅余15个人为止。请问怎样排法，才能使每次投入大海的都是非教徒

*/

 

namespace ConsoleApplication1
{
    class person
    {
        public bool isOnBoard { get; set; }
    }
}

 

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            person[] persons = new person[30];

            for (int i = 0; i < 30; i++)
            {
                persons[i] = new person();
                persons[i].isOnBoard = true;
            }

            int leftCount = 30;
            int currentID = -1;  //上一次丢到海里的persons数组的索引
            while (leftCount > 15)
            {
                int currentNumber = 0;  //当前计数
                for (int i = 1; i < 30; i++)
                {
                    if (persons[(currentID + i) % 30].isOnBoard == true)
                    {
                        currentNumber++;
                    }
                    if (currentNumber == 9)
                    {
                        leftCount--;
                        currentID = (currentID + i) % 30;
                        persons[currentID].isOnBoard = false;
                        currentNumber = 0;
                        break;
                    }
                }
            }

            //验证
            //@：留在船上 +：丢到海里
            for (int i = 0; i < 30; i++)
            {
                if (persons[i].isOnBoard == true)
                {
                    System.Console.Write("@");
                }
                else
                {
                    System.Console.Write("+");
                }
            }

                System.Console.ReadLine();
        }
    }
}