示例#1
0
        static void Main(string[] args)
        {
            var n            = 1000;
            var multiplyBy10 = 4;

            for (var i = 0; i < multiplyBy10; i++)
            {
                Console.WriteLine("n=" + n);
                // 构造表
                var bst  = new BinarySearchST <string, int>(n);
                var mst  = new MoveToFrontArrayST <string, int>(n);
                var keys = SearchCompare.GetRandomArrayString(n, 3, 20);
                for (var j = 0; j < n; j++)
                {
                    bst.Put(keys[j], j);
                    mst.Put(keys[j], j);
                }
                // 构造查询
                Array.Sort(keys);
                var querys = new string[10 * n];
                int queryIndex = 0, keyIndex = 0;
                while (queryIndex < querys.Length)
                {
                    var searchTimes = (int)Math.Ceiling((Math.Pow(0.5, keyIndex + 1) * querys.Length));

                    for (var j = 0; j < searchTimes && queryIndex < querys.Length; j++)
                    {
                        querys[queryIndex++] = keys[keyIndex];
                    }
                    keyIndex++;
                }
                Shuffle(querys);

                var sw = new Stopwatch();
                // 测试 MoveToFrontArrayST
                sw.Start();
                for (var j = 0; j < querys.Length; j++)
                {
                    mst.Get(querys[j]);
                }
                sw.Stop();
                Console.WriteLine("MoveToFrontArrayST: " + sw.ElapsedMilliseconds);

                // 测试 BinarySearchST
                sw.Restart();
                for (var j = 0; j < querys.Length; j++)
                {
                    bst.Get(querys[j]);
                }
                sw.Stop();
                Console.WriteLine("BinarySearchST: " + sw.ElapsedMilliseconds);

                n *= 10;
            }
        }
        static void Test(IST <string, int>[] sts, int n)
        {
            var sw    = new Stopwatch();
            var data  = SearchCompare.GetRandomArrayString(n, 3, 10);
            var item1 = "item1";

            Array.Sort(data);

            // 有序的数组
            Console.Write("Sorted Array: ");
            sw.Start();
            for (var i = 0; i < n; i++)
            {
                sts[0].Put(data[i], i);
            }
            sw.Stop();
            Console.WriteLine(sw.ElapsedMilliseconds);

            // 逆序的数组
            Console.Write("Sorted Array Reversed: ");
            sw.Restart();
            for (var i = n - 1; i >= 0; i--)
            {
                sts[1].Put(data[i], i);
            }
            sw.Stop();
            Console.WriteLine(sw.ElapsedMilliseconds);

            // 只有一种键
            Console.Write("One Distinct Key: ");
            sw.Restart();
            for (var i = 0; i < n; i++)
            {
                sts[2].Put(item1, i);
            }
            sw.Stop();
            Console.WriteLine(sw.ElapsedMilliseconds);

            // 只有两种值
            Console.Write("Two Distinct Values: ");
            sw.Restart();
            for (var i = 0; i < n; i++)
            {
                sts[3].Put(data[i], i % 2);
            }
            sw.Stop();
            Console.WriteLine(sw.ElapsedMilliseconds);
        }
        static void Main(string[] args)
        {
            var n            = 1000;
            var multiplyBy10 = 4;

            // 调和级数
            var harmonicNumber = new double[n * (int)Math.Pow(10, multiplyBy10)];

            harmonicNumber[0] = 1;
            for (var i = 1; i < harmonicNumber.Length; i++)
            {
                harmonicNumber[i] = harmonicNumber[i - 1] + 1 / (i + 1);
            }

            for (var i = 0; i < multiplyBy10; i++)
            {
                Console.WriteLine("n=" + n);
                // 构造表
                var mst1 = new MoveToFrontArrayST <string, int>(n);
                var mst2 = new MoveToFrontArrayST <string, int>(n);
                var keys = SearchCompare.GetRandomArrayString(n, 3, 20);
                for (var j = 0; j < n; j++)
                {
                    mst1.Put(keys[j], j);
                    mst2.Put(keys[j], j);
                }
                // 构造查询
                Array.Sort(keys);
                var queryZipf = new string[10 * n];
                int queryIndex = 0, keyIndex = 0;
                while (queryIndex < queryZipf.Length)
                {
                    var searchTimes = (int)Math.Ceiling(queryZipf.Length / (harmonicNumber[keyIndex + 1] * (i + 1)));

                    for (var j = 0; j < searchTimes && queryIndex < queryZipf.Length; j++)
                    {
                        queryZipf[queryIndex++] = keys[keyIndex];
                    }
                    keyIndex++;
                }

                var querys = new string[10 * n];
                queryIndex = 0;
                keyIndex   = 0;
                while (queryIndex < querys.Length)
                {
                    var searchTimes = (int)Math.Ceiling((Math.Pow(0.5, keyIndex + 1) * querys.Length));

                    for (var j = 0; j < searchTimes && queryIndex < querys.Length; j++)
                    {
                        querys[queryIndex++] = keys[keyIndex];
                    }
                    keyIndex++;
                }
                // Shuffle(querys);

                var sw = new Stopwatch();
                // 测试 3.1.33 的序列
                sw.Start();
                for (var j = 0; j < queryZipf.Length; j++)
                {
                    mst1.Get(querys[j]);
                }
                sw.Stop();
                Console.WriteLine("3.1.33 Best: " + sw.ElapsedMilliseconds);

                // 测试 Zipf
                sw.Restart();
                for (var j = 0; j < queryZipf.Length; j++)
                {
                    mst2.Get(queryZipf[j]);
                }
                sw.Stop();
                Console.WriteLine("Zipf: " + sw.ElapsedMilliseconds);

                n *= 10;
            }
        }