随机点名

class Program
    {
        static int number = 9;
        static List<int> arr = new List<int>();
        static void Main(string[] args)
        {
            rollCall();
        }
        static void rollCall()
        {
            string[] arrStrs = File.ReadAllLines("arrText.txt");
            if(arrStrs.Length > 0)
            {
                foreach (var item in arrStrs)
                {
                    arr.Add(int.Parse(item));
                }
            }
            
            while (Console.ReadLine() != "end")
            {
                Console.WriteLine(GetRandomNumber(arr));
            }

            string[] tempArr = new string[arr.Count];
            for (int i = 0; i < arr.Count; i++)
            {
                tempArr[i] = arr[i].ToString();
            }
            File.WriteAllLines("arrText.txt", tempArr);

        }
        static int GetRandomNumber(List<int> arr)
        {
            if(arr.Count <= 0)
            {
                int arrLength = number;
                for(int i = 0; i < arrLength; i++)
                {
                    arr.Add(i + 1);
                }
            }
            Random random = new Random();
            int randomIndex = random.Next(0, arr.Count);
            int temp = arr[randomIndex];
            arr.RemoveAt(randomIndex);
            return temp;
        }
    }