二叉查找树
1 using System; 2 3 public class BinarySearchTree 4 { 5 public int value; 6 7 public BinarySearchTree left = null; 8 public BinarySearchTree right = null; 9 public BinarySearchTree parent = null; 10 public BinarySearchTree root = null; 11 12 private bool _isRoot; 13 public bool isRoot 14 { 15 get { return _isRoot; } 16 set 17 { 18 _isRoot = value; 19 root = _isRoot ? this : null; 20 } 21 } 22 23 public BinarySearchTree(int value,BinarySearchTree parent,BinarySearchTree root) 24 { 25 this.value = value; 26 this.parent = parent; 27 this.root = root; 28 } 29 public BinarySearchTree(int value) : this(value, null, null) { } 30 31 /// <summary> 32 /// 增 33 /// </summary> 34 /// <param name="value"></param> 35 /// <returns></returns> 36 public void InsertNode(int value) 37 { 38 if(value <= this.value) 39 { 40 if(left == null) 41 { 42 left = new BinarySearchTree(value,this,root); 43 return; 44 } 45 else if(left != null) 46 { 47 left.InsertNode(value); 48 return; 49 } 50 } 51 else if(value > this.value) 52 { 53 if(right == null) 54 { 55 right = new BinarySearchTree(value,this,root); 56 return; 57 } 58 else if(right != null) 59 { 60 right.InsertNode(value); 61 return; 62 } 63 } 64 } 65 66 /// <summary> 67 /// 删 68 /// </summary> 69 /// <param name="value"></param> 70 /// <exception cref="Exception"/> 71 public void RemoveNode(int value) 72 { 73 BinarySearchTree beRemove = null; 74 try 75 { 76 beRemove = Find(value); 77 } 78 catch (Exception) 79 { 80 throw new Exception("被删除的数字不存在"); 81 } 82 83 if (beRemove.left == null && beRemove.right == null) 84 { 85 if (beRemove.parent.left == beRemove) 86 { 87 beRemove.parent.left = null; 88 } 89 else if (beRemove.parent.right == beRemove) 90 { 91 beRemove.parent.right = null; 92 } 93 } 94 else if(beRemove.left != null && beRemove.right == null) 95 { 96 if (beRemove.parent.left == beRemove) 97 { 98 beRemove.parent.left = beRemove.left; 99 } 100 else if (beRemove.parent.right == beRemove) 101 { 102 beRemove.parent.right = beRemove.left; 103 } 104 } 105 else if(beRemove.left == null && beRemove.right != null) 106 { 107 if (beRemove.parent.left == beRemove) 108 { 109 beRemove.parent.left = beRemove.right; 110 } 111 else if (beRemove.parent.right == beRemove) 112 { 113 beRemove.parent.right = beRemove.right; 114 } 115 } 116 else if(beRemove.left != null && beRemove.right != null) 117 { 118 if (beRemove.parent.left == beRemove) 119 { 120 beRemove.parent.left = beRemove.right; 121 } 122 else if (beRemove.parent.right == beRemove) 123 { 124 beRemove.parent.right = beRemove.right; 125 } 126 127 beRemove.right.left = beRemove.left; 128 } 129 } 130 131 /// <summary> 132 /// 改 133 /// </summary> 134 /// <param name="newValue"></param> 135 public void ChangeNoodTo(int newValue) 136 { 137 RemoveNode(value); 138 root.InsertNode(newValue); 139 } 140 141 /// <summary> 142 /// 查 143 /// </summary> 144 /// <param name="value"></param> 145 /// <returns></returns> 146 /// <exception cref="Exception"/> 147 public BinarySearchTree Find(int value) 148 { 149 if (value < this.value) 150 { 151 //return left == null ? -1 : left.Find(value); 152 if(left == null) 153 { 154 throw new Exception("被搜索的数字不存在"); 155 } 156 else 157 { 158 return left.Find(value); 159 } 160 } 161 else if (value > this.value) 162 { 163 //return right == null ? -1 : right.Find(value); 164 if(right == null) 165 { 166 throw new Exception("被搜索的数字不存在"); 167 } 168 else 169 { 170 return right.Find(value); 171 } 172 } 173 else if (value == this.value) 174 { 175 return this; 176 } 177 178 throw new Exception("被搜索的数字不存在"); 179 } 180 181 /// <summary> 182 /// 输出这棵二叉搜索树 183 /// </summary> 184 public void ShowTree() 185 { 186 Console.Write("("); 187 Console.Write(this.value); 188 if(left == null) 189 { 190 Console.Write("()"); 191 } 192 else 193 { 194 left.ShowTree(); 195 } 196 197 if(right == null) 198 { 199 Console.Write("()"); 200 } 201 else 202 { 203 right.ShowTree(); 204 } 205 206 Console.Write(")"); 207 } 208 209 /// <summary> 210 /// 复写 ToString() 方法 211 /// </summary> 212 /// <returns></returns> 213 public override string ToString() 214 { 215 return value.ToString(); 216 } 217 }
1 class Program 2 { 3 4 private static int[] value = new int[] { 50, 60, 70, 23, 51, 159, 25 }; 5 6 static void Main(string[] args) 7 { 8 BinarySearchTree rootNood = new BinarySearchTree(value[0]); 9 rootNood.isRoot = true; 10 11 Console.WriteLine(rootNood.root == null); 12 13 for (int i = 1; i < value.Length; i++) 14 { 15 rootNood.InsertNode(value[i]); 16 } 17 18 rootNood.ShowTree(); 19 Console.WriteLine(); 20 21 rootNood.Find(23).ChangeNoodTo(24); 22 rootNood.ShowTree(); 23 24 25 Console.ReadKey(); 26 } 27 }