红黑树

Author: tianqing.liang

19-AVL-Tree/Main.dart

@@ -2,6 +2,7 @@ import 'FileOperator.dart';
 import 'BST.dart';
 import 'AVLTree.dart';
 
+
 void main() async{
 
   print("Pride and Prejudice");

20-Red-Black-Tree/AVLTree.dart

@@ -45,7 +45,7 @@ class AVLTree<K extends Comparable<K>, V> {
         1 + [_getHeight(node.left), _getHeight(node.right)].reduce(max);
     // 计算平衡因子
     int balanceFactor = getBalanceFactor(node);
-    if (balanceFactor> 1 && getBalanceFactor(node.left) >= 0) {
+    if (balanceFactor > 1 && getBalanceFactor(node.left) >= 0) {
       return _rightRotate(node);
     }
 //
@@ -240,18 +240,19 @@ class AVLTree<K extends Comparable<K>, V> {
       // 用这个节点顶替待删除节点的位置
       _Node successor = _minimum(node.right!);
       //w维持平衡性操作，不再执行removemin
-      successor.right = _removeNode(node.right!,successor._key);
+      successor.right = _removeNode(node.right!, successor._key);
       successor.left = node.left;
       node.left = node.right = null;
 //      return successor;
       retNode = successor;
     }
-    if(retNode == null) {
+    if (retNode == null) {
       return null;
     }
 
     // 更新height
-    retNode.height = 1 + [_getHeight(retNode.left), _getHeight(retNode.right)].reduce(max);
+    retNode.height =
+        1 + [_getHeight(retNode.left), _getHeight(retNode.right)].reduce(max);
 
     // 计算平衡因子
     int balanceFactor = getBalanceFactor(retNode);
@@ -278,7 +279,6 @@ class AVLTree<K extends Comparable<K>, V> {
     }
 
     return retNode;
-
   }
 
   // 删除掉以node为根的二分搜索树中的最小节点

20-Red-Black-Tree/Main.dart

@@ -0,0 +1,78 @@
+import 'FileOperator.dart';
+import 'BST.dart';
+import 'AVLTree.dart';
+import 'RBTree.dart';
+
+
+void main() async{
+
+  print("Pride and Prejudice");
+
+  List words = await FileOperator.getFileString('text2.txt');
+
+//  words.sort();
+
+  // Test BST
+  var now = new DateTime.now();
+  num startTime = now.millisecondsSinceEpoch;
+
+  BST<String, num> bst = BST();
+  for (String word in words) {
+    if (bst.contains(word))
+      bst.set(word, bst.get(word) + 1);
+    else
+      bst.add(word, 1);
+  }
+
+  for(String word in words)
+    bst.contains(word);
+
+  var endNow = new DateTime.now();
+  num endTime = endNow.millisecondsSinceEpoch;
+
+  double time = (endTime - startTime) / 1000.0;
+  print("BST:  $time  s");
+
+// Test AVL
+  var startNow1 = new DateTime.now();
+  var startTime1 = startNow1.millisecondsSinceEpoch;
+
+  AVLTree<String, num> avl = AVLTree();
+  for (String word in words) {
+    if (avl.contains(word))
+      avl.set(word, avl.get(word) + 1);
+    else
+      avl.add(word, 1);
+  }
+
+  for(String word in words)
+    avl.contains(word);
+
+  var endNow1 = new DateTime.now();
+  var endTime1 = endNow1.millisecondsSinceEpoch;
+
+  double time3 = (endTime1 - startTime1) / 1000.0;
+  print("AVL:  $time3  s");
+
+  // Test BRTree
+  var startNow2 = new DateTime.now();
+  var startTime2 = startNow2.millisecondsSinceEpoch;
+
+  RBTree<String, num> rb = RBTree();
+  for (String word in words) {
+    if (rb.contains(word))
+      rb.set(word, rb.get(word) + 1);
+    else
+      rb.add(word, 1);
+  }
+
+  for(String word in words)
+    avl.contains(word);
+  var endNow2 = new DateTime.now();
+  var endTime2 = endNow2.millisecondsSinceEpoch;
+
+  double time2 = (endTime2 - startTime2) / 1000.0;
+  print("RBTree:  $time2  s");
+
+
+}

20-Red-Black-Tree/Main2.dart

@@ -0,0 +1,65 @@
+import 'FileOperator.dart';
+import 'BST.dart';
+import 'AVLTree.dart';
+import 'dart:math';
+import 'RBTree.dart';
+
+
+void main() async{
+
+
+  // int n = 20000000;
+  int n = 1000000;
+
+  Random random = new Random(n);
+
+  List testData = List.empty(growable: true);
+
+  for(int i = 0 ; i < n ; i ++)
+    testData.add(random.nextInt(1<<32));
+
+  // Test BST
+  var now = new DateTime.now();
+  num startTime = now.millisecondsSinceEpoch;
+
+  BST<num, num> bst = BST();
+  for (num x in testData)
+    bst.add(x, 0);
+
+  var endNow = new DateTime.now();
+  num endTime = endNow.millisecondsSinceEpoch;
+
+  double time = (endTime - startTime) / 1000.0;
+  print("BST:  $time  s");
+
+// Test AVL
+  var startNow1 = new DateTime.now();
+  var startTime1 = startNow1.millisecondsSinceEpoch;
+
+  AVLTree<num, num> avl = AVLTree();
+  for (num word in testData) {
+      avl.add(word, 1);
+  }
+  var endNow1 = new DateTime.now();
+  var endTime1 = endNow1.millisecondsSinceEpoch;
+
+  time = (endTime1 - startTime1) / 1000.0;
+  print("AVL:  $time  s");
+
+  // Test BRTree
+  var startNow2 = new DateTime.now();
+  var startTime2 = startNow2.millisecondsSinceEpoch;
+
+  RBTree<num, num> rb = RBTree();
+  for (num word in testData) {
+      rb.add(word, 1);
+  }
+
+  var endNow2 = new DateTime.now();
+  var endTime2 = endNow2.millisecondsSinceEpoch;
+
+  double time2 = (endTime2 - startTime2) / 1000.0;
+  print("RBTree:  $time2  s");
+
+
+}