public class BloomFilter

    {

        public BitArray _BloomArray;

        public Int64 BloomArryLength { get; }

        public Int64 DataArrayLeng { get; }

        public Int64 BitIndexCount { get; }

        /// <summary>

        /// 初始化

        /// </summary>

        /// <param name="BloomArryLength">布隆数组的大小</param>

        /// <param name="DataArrayLeng">数据的长度</param>

        /// <param name="bitIndexCount">hash数</param>

        public BloomFilter(int BloomArryLength,int DataArrayLeng,int bitIndexCount)

        {

            _BloomArray = new BitArray(BloomArryLength);

            this.BloomArryLength = BloomArryLength;

            this.DataArrayLeng = DataArrayLeng;

            this.BitIndexCount = bitIndexCount;

        }

        public void Add(string str)

        {

            var hashCode = GetHashCode(str);

            Random random = new Random(hashCode);

            for (int i = ; i < BitIndexCount; i++)

            {

                var c = random.Next((int)(this.BloomArryLength - ));

                _BloomArray[c] = true;

            }

        }

        public bool isExist(string str)

        {

            var hashCode = GetHashCode(str);

            Random random = new Random(hashCode);

            for (int i = ; i < BitIndexCount; i++)

            {

                if(!_BloomArray[random.Next((int)(this.BloomArryLength - ))])

                {

                    return false;

                }

            }

            return true;

        }

        public int GetHashCode(object value)

        {

            return value.GetHashCode();

        }

        public double getFalsePositiveProbability()

        {

            // (1 - e^(-k * n / m)) ^ k

            return Math.Pow(( - Math.Exp(-BitIndexCount * (double)DataArrayLeng / BloomArryLength)),

                    BitIndexCount);

        }

    }

        static void Main(string[] args)

        {

            Bloom_Filter.BloomFilter bloom = new Bloom_Filter.BloomFilter(, , );//五千万条数据

            for (int i = ; i < bloom.DataArrayLeng; i++)//五千万条数据

            {

                bloom.Add(i.ToString());

            }

            do

            {

                var c = Console.ReadLine();

                if (c == "e")

                    break;

                Stopwatch sw = new Stopwatch();

                sw.Start();

                var temp=bloom.isExist(c);

                sw.Stop();

                Console.WriteLine($"查找:{c}\n结果:{temp}\n总耗时:{sw.ElapsedTicks}\n错误概率:{bloom.getFalsePositiveProbability()}");

            } while (true);

        }