Merge pull request #65 from zhaohuXing/master

JVM6

group11/1178243325/week12/build.gradle

@@ -0,0 +1,9 @@
+apply plugin: 'java'
+
+repositories {
+	mavenCentral()
+}
+
+dependencies {
+	testCompile("junit:junit:4.12")
+}

group11/1178243325/week12/readme.md

@@ -0,0 +1,11 @@
+## 讲课内容：
+
+## 第12周作业(JVM7)（05-08 至 05-14)
+- 数据结构，实现FileList.java(给定一个目录, 递归的列出下面所以的子目录和文件)
+- 实现BinaryTreeUtil.java, 包括用递归方式来实现对二叉树的前序,中序,后序遍历,用非递归方式实现对二叉树的前序和中序遍历,需要通过测试用例BinaryTreeUtilTest.java
+- 写一篇文章
+
+## 完成情况：
+
+## 我的收获：
+其实最难是坚持

group11/1178243325/week12/src/main/java/com/sprint/datastructure/tree/BinaryTreeNode.java

@@ -0,0 +1,64 @@
+package com.sprint.datastructure.tree;
+
+public class BinaryTreeNode<T extends Comparable> {
+	private T data;
+	private BinaryTreeNode<T> left;
+	private BinaryTreeNode<T> right;
+
+	public BinaryTreeNode(T data) {
+		this.data = data;
+	} 
+	//setter && getter
+	public void setData(T data) {
+		this.data = data;
+	}
+	public T getData() {
+		return data;
+	}
+
+	public void setLeft(BinaryTreeNode<T> left) {
+		this.left = left;
+	}
+	public BinaryTreeNode<T> getLeft() {
+		return left;
+	}
+
+	public void setRight(BinaryTreeNode<T> right) {
+		this.right = right;
+	}
+	public BinaryTreeNode<T> getRight() {
+		return right;
+	}
+
+	public BinaryTreeNode<T> insert(T data) {
+		//二叉树的基本原则:
+		//	left.data < this.data < right.data
+		if (this.data == null) {
+			this.data = data;
+			return this;
+		}
+
+		int compareResult = this.data.compareTo(data);
+		if (compareResult > 0) {
+			//插入的data 小于 this.data
+			if (this.left == null) {
+				this.left = new BinaryTreeNode<T>(data);
+				return this.left;
+			} else {
+				return this.left.insert(data);
+			}
+		} else if (compareResult < 0) {
+			//插入的data 大于 this.data
+			if (this.right == null) {
+				this.right = new BinaryTreeNode<T>(data);
+				this.right.data = data;
+				return this.right;
+			} else {
+				return this.right.insert(data);
+			}
+		} else {
+			//二叉树中不存在重复的元素
+			return this;	
+		}
+	}
+}

group11/1178243325/week12/src/main/java/com/sprint/datastructure/tree/BinaryTreeUtil.java

@@ -0,0 +1,112 @@
+package com.sprint.datastructure.tree;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Stack;
+public class BinaryTreeUtil {
+	/**
+	 * 用递归的方式实现对二叉树的前序遍历，需要通过BinaryTreeUtil测试用例
+	 * @param root
+	 * @return 
+	 */		
+	public static <T extends Comparable> List<T> preOrderVisit(BinaryTreeNode<T> root) {
+		List<T> result = new ArrayList<T>();
+		preOrderVisit(root, result);
+		return result;
+	}
+
+	private static <T extends Comparable> void preOrderVisit(BinaryTreeNode<T> root, List<T> values) {
+		if (root != null) {
+			values.add(root.getData());
+			preOrderVisit(root.getLeft(), values);
+			preOrderVisit(root.getRight(), values);
+		}
+	}
+
+	/**
+	 * 用递归的方式实现对二叉树的中序遍历，需要通过BinaryTreeUtil测试用例
+	 * @param root
+	 * @return 
+	 */		
+	public static <T extends Comparable> List<T> inOrderVisit(BinaryTreeNode<T> root) {
+		List<T> result = new ArrayList<T>();
+		inOrderVisit(root, result);
+		return result;
+	}
+
+	private static <T extends Comparable> void inOrderVisit(BinaryTreeNode<T> root, List<T> values) {
+		if (root != null) {
+			inOrderVisit(root.getLeft(), values);
+			values.add(root.getData());
+			inOrderVisit(root.getRight(), values);
+		}
+	}
+	/**
+	 * 用递归的方式实现对二叉树的后序遍历，需要通过BinaryTreeUtil测试用例
+	 * @param root
+	 * @return 
+	 */		
+	public static <T extends Comparable> List<T> postOrderVisit(BinaryTreeNode<T> root) {
+		List<T> result = new ArrayList<T>();
+		postOrderVisit(root, result);
+		return result;
+	}
+
+	private static <T extends Comparable> void postOrderVisit(BinaryTreeNode<T> root, List<T> values) {
+		if (root != null) {
+			postOrderVisit(root.getLeft(), values);
+			postOrderVisit(root.getRight(), values);
+			values.add(root.getData());
+		}
+	}
+
+	/**
+	 * 用非递归的方式实现二叉树的前序遍历
+	 * @param root
+	 * @return
+	 */
+	public static <T extends Comparable> List<T> preOrderWithoutRecursion(BinaryTreeNode<T> root) {
+		List<T> result = new ArrayList<T>();
+		Stack<BinaryTreeNode<T>> stack = new Stack<BinaryTreeNode<T>>();
+		if (root != null) {
+			stack.push(root);
+			while (!stack.isEmpty()) {
+				BinaryTreeNode<T> node = (BinaryTreeNode<T>)stack.peek();
+				while (node != null) {
+					result.add(node.getData());
+					stack.push(node.getLeft());
+					node = stack.peek();
+				}
+				node = stack.pop();
+				if (!stack.isEmpty()) {
+					node = stack.pop();
+					stack.push(node.getRight());
+				}
+			}
+
+		}
+		return result;
+	}
+
+	/**
+	 * 用非递归的方式实现二叉树的中序遍历
+	 * @param root
+	 * @return
+	 */
+	public static <T extends Comparable> List<T> inOrderWithoutRecursion(BinaryTreeNode<T> root) {
+		List<T> result = new ArrayList<T>();
+		Stack<BinaryTreeNode<T>> stack = new Stack<BinaryTreeNode<T>>();
+		BinaryTreeNode<T> node = root;
+		while (node != null || !stack.isEmpty()) {
+			if (node != null) {
+				stack.push(node);
+				node = node.getLeft();
+			} else {
+				node = stack.pop();
+				result.add(node.getData());
+				node = node.getRight();
+			}
+		} 
+		return result;
+	}
+}

group11/1178243325/week12/src/main/java/com/sprint/datastructure/tree/FileList.java

@@ -0,0 +1,8 @@
+package com.sprint.datastructure.tree;
+
+import java.io.File;
+public class FileList {
+	public void list(File f) {
+
+	}	
+}

group11/1178243325/week12/src/test/java/com/sprint/datastructure/tree/BinaryTreeUtilTest.java

@@ -0,0 +1,66 @@
+package com.sprint.datastructure.tree;
+
+import java.util.List;
+import org.junit.After;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+public class BinaryTreeUtilTest {
+
+	BinaryTreeNode<Integer> root = null;
+	@Before
+	public void setUp() throws Exception {
+		root = new BinaryTreeNode<Integer>(1);
+		root.setLeft(new BinaryTreeNode<Integer>(2));
+		root.setRight(new BinaryTreeNode<Integer>(5));
+		root.getLeft().setLeft(new BinaryTreeNode<Integer>(3));
+		root.getLeft().setRight(new BinaryTreeNode<Integer>(4));
+	}
+
+	@Test
+	public void testPreOrderVisit() {
+
+		List<Integer> result = BinaryTreeUtil.preOrderVisit(root);
+		Assert.assertEquals("[1, 2, 3, 4, 5]", result.toString());
+
+
+	}
+	@Test
+	public void testInOrderVisit() {
+
+		List<Integer> result = BinaryTreeUtil.inOrderVisit(root);
+		Assert.assertEquals("[3, 2, 4, 1, 5]", result.toString());		
+
+	}
+
+	@Test
+	public void testPostOrderVisit() {
+
+		List<Integer> result = BinaryTreeUtil.postOrderVisit(root);
+		Assert.assertEquals("[3, 4, 2, 5, 1]", result.toString());		
+
+	}
+
+
+	@Test
+	public void testInOrderVisitWithoutRecursion() {
+		BinaryTreeNode<Integer> node = root.getLeft().getRight();
+		node.setLeft(new BinaryTreeNode<Integer>(6));
+		node.setRight(new BinaryTreeNode<Integer>(7));
+
+		List<Integer> result = BinaryTreeUtil.inOrderWithoutRecursion(root);
+		Assert.assertEquals("[3, 2, 6, 4, 7, 1, 5]", result.toString());		
+
+	}
+	@Test
+	public void testPreOrderVisitWithoutRecursion() {
+		BinaryTreeNode<Integer> node = root.getLeft().getRight();
+		node.setLeft(new BinaryTreeNode<Integer>(6));
+		node.setRight(new BinaryTreeNode<Integer>(7));
+
+		List<Integer> result = BinaryTreeUtil.preOrderWithoutRecursion(root);
+		Assert.assertEquals("[1, 2, 3, 4, 6, 7, 5]", result.toString());		
+
+	}
+}