update three array questions

Author: jackzhenguo

Array/Array.Lib/ContainsDuplicateIISln.cs

@@ -0,0 +1,37 @@
+/* ==============================================================================
+ * 功能描述：ContainsDuplicateIISln  
+ * 创 建 者：gz
+ * 创建日期：2017/5/3 18:25:02
+ * ==============================================================================*/
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace Array.Lib
+{
+    /// <summary>
+    /// ContainsDuplicateIISln
+    /// </summary>
+    public class ContainsDuplicateIISln
+    {
+        public bool ContainsNearbyDuplicate(int[] nums, int k)
+        {
+            Dictionary<int, int> dict = new Dictionary<int, int>(); //元素值，索引
+            for (int i = 0; i < nums.Length; i++)
+            {
+                if (dict.ContainsKey(nums[i]))
+                {
+                    if (Math.Abs(i - dict[nums[i]]) <= k)
+                        return true;
+                    dict.Remove(nums[i]); //移调
+                    dict.Add(nums[i], i);//添加最新的
+                    continue;
+                }
+                dict.Add(nums[i], i);
+            }
+            return false;
+        }
+
+    }
+}

Array/Array.Lib/DisappearElementsSln.cs

@@ -0,0 +1,42 @@
+/* ==============================================================================
+ * 功能描述：Class1  
+ * 创 建 者：gz
+ * 创建日期：2017/5/3 18:55:55
+ * ==============================================================================*/
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace Array.Lib
+{
+    //Given an array of integers where 1 ≤ a[i] ≤ n (n = size of array), some elements appear twice and others appear once.
+
+    //Find all the elements of [1, n] inclusive that do not appear in this array.
+
+    //Could you do it without extra space and in O(n) runtime? You may assume the returned list does not count as extra space.
+    public class DisappearElementsSln
+    {
+        public IList<int> FindDisappearedNumbers(int[] nums)
+        {
+            IList<int> rtn = new List<int>();
+            for (int i = 0; i < nums.Length; i++)
+                rtn.Add(i + 1);
+            return rtn.Except(nums).ToList(); //求差集应用在这个场合效率不好，为充分挖掘题目
+        }
+
+        public IList<int> FindDisappearedNumbers2(int[] nums)
+        {
+            System.Array.Sort(nums);
+            IList<int> rtn = new List<int>();
+            for (int i = 0; i < nums.Length; i++)
+            {
+                int val = i + 1;
+                
+                
+            }
+            return rtn;
+        }
+
+    }
+}

Array/Array.Lib/RotateArraySln.cs

@@ -0,0 +1,62 @@
+/* ==============================================================================
+ * 功能描述：RotateArraySln  
+ * 创 建 者：gz
+ * 创建日期：2017/5/3 16:03:03
+ * ==============================================================================*/
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.Linq;
+using System.Text;
+
+namespace Array.Lib
+{
+    /// <summary>
+    /// RotateArraySln
+    /// </summary>
+    public class RotateArraySln
+    {
+        public void Rotate(int[] nums, int k)
+        {
+            int n = nums.Length;
+            if (n == 0 || n == 1) return;
+            if ((double)k / n > 1)
+                k = k % n;
+            if (k == 0) return;
+            System.Array.Reverse(nums, 0, n - k); //index, length
+            System.Array.Reverse(nums, n - k, k);
+            System.Array.Reverse(nums);
+        }
+
+        public void Rotate2(int[] nums, int k)
+        {
+            int n = nums.Length;
+            if (n == 0 || n == 1) return;
+            if ((double)k / n > 1)
+                k = k % n;
+            if (k == 0) return;
+            Reverse(nums, 0, n - k); //index, length
+            Reverse(nums, n - k, k);
+            Reverse(nums, 0, n);
+        }
+
+        private void Reverse(int[] nums, int index, int length)
+        {
+            int i = 0;
+            int loop = length/2;
+            while (i < loop)
+            {
+                swap(ref nums[index + i], ref nums[length + index - i - 1]);
+                i++;
+            }
+        }
+
+        private void swap(ref int a, ref int b)
+        {
+            int tmp = a;
+            a = b;
+            b = tmp;
+        }
+
+    }
+}