WildWei

        /// <summary>
        /// Find Missing Number        
        /// <param name="nums">input num int array</param>
        /// <returns></returns>
        private static int FindMissingNumber(int[] nums)
        {
            int result = 0;
            int i = 0;

            for (i = 0; i < nums.Length; i++)

WildWei

        private static int GetSingleNumberByDictionary(int[] nums)
        {

            Dictionary<int, int> dic = new Dictionary<int, int>();

            int value = 0;
            foreach (int num in nums)
            {
                if (dic.TryGetValue(num, out value))
                {

WildWei

        private static int GetSingleNumberByHashSet(int[] nums)
        {

            HashSet<int> numList = new HashSet<int>();

            foreach (int num in nums)
            {
                if (numList.Contains(num))
                {
                    numList.Remove(num);

WildWei

        private static int GetSingleNumber(int[] nums)
        {
            int singleNumber = 0;

            foreach (var num in nums)
            {
                singleNumber = singleNumber ^ num;
            }

            return singleNumber;

WildWei

    public class Person
    {
        /// <summary>
        /// 男:M , 女:F
        /// </summary>
        public char gender { get; set; }

        /// <summary>
        /// 年齡
        /// </summary>

WildWei

        static int BinarySearch(int[] inputArray,int target)
        {
            int low = 0;
            int high = inputArray.Length - 1;

            while (high >= low)
            {
                int middle = (low + high) / 2;
                if (inputArray[middle] == target)
                {

WildWei

        public static void sayHelloKitty(int number)
        {
            for (int i = 0; i < number; i++)
            {
                Console.WriteLine($"Hello Kitty {number}");
            }

            for (int j = 0; j < number; j++)
            {
                Console.WriteLine($"Hello Kitty {number}");

WildWei

        public static void sayHelloKitty(int number)
        {
            for (int i = 0; i < number; i++)
            {
                for (int j = 0; j < number; j++)
                {
                    Console.WriteLine($"Hello Kitty {number}");
                }
            }

WildWei

        public static void sayHelloKitty(int number)
        {
            for (int i = 0; i < number; i++)
            {
                Console.WriteLine($"Hello Kitty {number}");
            }

            return;
        }

WildWei

        public static void helloKitty(int number)
        {
            for (int i = 0; i < 10; i++)
            {
                Console.WriteLine($"Hello Kitty {i}");
            }

            return;
        }