Merge pull request #8 from algorithmzuo/master

20201209

src/class06/Test.java

@@ -1,5 +0,0 @@
-package class06;
-
-public class Test {
-
-}

src/class06_09/Code01_LinkedListMid.java

@@ -1,4 +1,4 @@
-package class06;
+package class06_09;
 
 import java.util.ArrayList;
 

src/class06_09/Code02_IsPalindromeList.java

@@ -1,4 +1,4 @@
-package class06;
+package class06_09;
 
 import java.util.Stack;
 

src/class06_09/Code03_SmallerEqualBigger.java

@@ -1,4 +1,4 @@
-package class06;
+package class06_09;
 
 public class Code03_SmallerEqualBigger {
 

src/class06_09/Code04_CopyListWithRandom.java

@@ -1,4 +1,4 @@
-package class06;
+package class06_09;
 
 import java.util.HashMap;
 

src/class06_10/Code01_FindFirstIntersectNode.java

@@ -1,6 +1,6 @@
-package class06;
+package class06_10;
 
-public class Code05_FindFirstIntersectNode {
+public class Code01_FindFirstIntersectNode {
 
 	public static class Node {
 		public int value;

src/class07/Code08_PaperFolding.java

@@ -1,24 +0,0 @@
-package class07;
-
-public class Code08_PaperFolding {
-
-	public static void printAllFolds(int N) {
-		printProcess(1, N, true);
-	}
-
-	// 递归过程，来到了某一个节点，
-	// i是节点的层数，N一共的层数，down == true  凹    down == false 凸
-	public static void printProcess(int i, int N, boolean down) {
-		if (i > N) {
-			return;
-		}
-		printProcess(i + 1, N, true);
-		System.out.println(down ? "凹 " : "凸 ");
-		printProcess(i + 1, N, false);
-	}
-
-	public static void main(String[] args) {
-		int N = 3;
-		printAllFolds(N);
-	}
-}

src/class07_10/Code01_RecursiveTraversalBT.java

@@ -1,4 +1,4 @@
-package class07;
+package class07_10;
 
 public class Code01_RecursiveTraversalBT {
 

src/class07_10/Code02_UnRecursiveTraversalBT.java

@@ -1,4 +1,4 @@
-package class07;
+package class07_10;
 
 import java.util.Stack;
 

src/class07_11/Code01_LevelTraversalBT.java

@@ -1,9 +1,9 @@
-package class07;
+package class07_11;
 
 import java.util.LinkedList;
 import java.util.Queue;
 
-public class Code03_LevelTraversalBT {
+public class Code01_LevelTraversalBT {
 
 	public static class Node {
 		public int value;

src/class07_11/Code02_SerializeAndReconstructTree.java

@@ -1,10 +1,10 @@
-package class07;
+package class07_11;
 
 import java.util.LinkedList;
 import java.util.Queue;
 import java.util.Stack;
 
-public class Code04_SerializeAndReconstructTree {
+public class Code02_SerializeAndReconstructTree {
     /*
      * 二叉树可以通过先序、后序或者按层遍历的方式序列化和反序列化，
      * 以下代码全部实现了。
@@ -129,7 +129,7 @@ public class Code04_SerializeAndReconstructTree {
 			Queue<Node> queue = new LinkedList<Node>();
 			queue.add(head);
 			while (!queue.isEmpty()) {
-				head = queue.poll();
+				head = queue.poll(); // head 父   子
 				if (head.left != null) {
 					ans.add(String.valueOf(head.left.value));
 					queue.add(head.left);

src/class07_11/Code03_EncodeNaryTreeToBinaryTree.java

@@ -0,0 +1,86 @@
+package class07_11;
+
+import java.util.ArrayList;
+import java.util.List;
+
+// 本题测试链接：https://leetcode.com/problems/encode-n-ary-tree-to-binary-tree
+public class Code03_EncodeNaryTreeToBinaryTree {
+
+	// 提交时不要提交这个类
+	public static class Node {
+		public int val;
+		public List<Node> children;
+
+		public Node() {
+		}
+
+		public Node(int _val) {
+			val = _val;
+		}
+
+		public Node(int _val, List<Node> _children) {
+			val = _val;
+			children = _children;
+		}
+	};
+
+	// 提交时不要提交这个类
+	public static class TreeNode {
+		int val;
+		TreeNode left;
+		TreeNode right;
+
+		TreeNode(int x) {
+			val = x;
+		}
+	}
+
+	// 只提交这个类即可
+	class Codec {
+		// Encodes an n-ary tree to a binary tree.
+		public TreeNode encode(Node root) {
+			if (root == null) {
+				return null;
+			}
+			TreeNode head = new TreeNode(root.val);
+			head.left = en(root.children);
+			return head;
+		}
+
+		private TreeNode en(List<Node> children) {
+			TreeNode head = null;
+			TreeNode cur = null;
+			for (Node child : children) {
+				TreeNode tNode = new TreeNode(child.val);
+				if (head == null) {
+					head = tNode;
+				} else {
+					cur.right = tNode;
+				}
+				cur = tNode;
+				cur.left = en(child.children);
+			}
+			return head;
+		}
+
+		// Decodes your binary tree to an n-ary tree.
+		public Node decode(TreeNode root) {
+			if (root == null) {
+				return null;
+			}
+			return new Node(root.val, de(root.left));
+		}
+
+		public List<Node> de(TreeNode root) {
+			List<Node> children = new ArrayList<>();
+			while (root != null) {
+				Node cur = new Node(root.val, de(root.left));
+				children.add(cur);
+				root = root.right;
+			}
+			return children;
+		}
+
+	}
+
+}

src/class07_11/Code04_PrintBinaryTree.java

@@ -1,6 +1,6 @@
-package class07;
+package class07_11;
 
-public class Code05_PrintBinaryTree {
+public class Code04_PrintBinaryTree {
 
 	public static class Node {
 		public int value;

src/class07_11/Code05_TreeMaxWidth.java

@@ -1,10 +1,10 @@
-package class07;
+package class07_11;
 
 import java.util.HashMap;
 import java.util.LinkedList;
 import java.util.Queue;
 
-public class Code06_TreeMaxWidth {
+public class Code05_TreeMaxWidth {
 
 	public static class Node {
 		public int value;

src/class07_11/Code06_SuccessorNode.java

@@ -1,6 +1,6 @@
-package class07;
+package class07_11;
 
-public class Code07_SuccessorNode {
+public class Code06_SuccessorNode {
 
 	public static class Node {
 		public int value;

src/class07_11/Code07_PaperFolding.java

@@ -0,0 +1,28 @@
+package class07_11;
+
+public class Code07_PaperFolding {
+
+	public static void printAllFolds(int N) {
+		process(1, N, true);
+		System.out.println();
+	}
+
+	// 当前你来了一个节点，脑海中想象的！
+	// 这个节点在第i层，一共有N层，N固定不变的
+	// 这个节点如果是凹的话，down = T
+	// 这个节点如果是凸的话，down = F
+	// 函数的功能：中序打印以你想象的节点为头的整棵树！
+	public static void process(int i, int N, boolean down) {
+		if (i > N) {
+			return;
+		}
+		process(i + 1, N, true);
+		System.out.print(down ? "凹 " : "凸 ");
+		process(i + 1, N, false);
+	}
+
+	public static void main(String[] args) {
+		int N = 4;
+		printAllFolds(N);
+	}
+}

src/class08_12/Code01_IsCBT.java

@@ -1,8 +1,8 @@
-package class08;
+package class08_12;
 
 import java.util.LinkedList;
 
-public class Code06_IsCBT {
+public class Code01_IsCBT {
 
 	public static class Node {
 		public int value;

src/class08_12/Code02_IsBST.java

@@ -1,8 +1,8 @@
-package class08;
+package class08_12;
 
 import java.util.ArrayList;
 
-public class Code03_IsBST {
+public class Code02_IsBST {
 
 	public static class Node {
 		public int value;

src/class08_12/Code03_IsBalanced.java

@@ -1,6 +1,6 @@
-package class08;
+package class08_12;
 
-public class Code01_IsBalanced {
+public class Code03_IsBalanced {
 
 	public static class Node {
 		public int value;

src/class08_12/Code04_IsFull.java

@@ -1,6 +1,6 @@
-package class08;
+package class08_12;
 
-public class Code02_IsFull {
+public class Code04_IsFull {
 
 	public static class Node {
 		public int value;

src/class08_12/Code05_MaxSubBSTSize.java

@@ -1,8 +1,8 @@
-package class08;
+package class08_12;
 
 import java.util.ArrayList;
 
-public class Code04_MaxSubBSTSize {
+public class Code05_MaxSubBSTSize {
 
 	public static class Node {
 		public int value;

src/class08_12/Code06_MaxSubBSTHead.java

@@ -1,8 +1,8 @@
-package class08;
+package class08_12;
 
 import java.util.ArrayList;
 
-public class Code05_MaxSubBSTHead {
+public class Code06_MaxSubBSTHead {
 
 	public static class Node {
 		public int value;

src/class08_12/Code07_lowestAncestor.java

@@ -1,4 +1,4 @@
-package class08;
+package class08_12;
 
 import java.util.ArrayList;
 import java.util.HashMap;

src/class08_12/Code08_MaxDistance.java

@@ -1,4 +1,4 @@
-package class08;
+package class08_12;
 
 import java.util.ArrayList;
 import java.util.HashMap;

src/class08_12/Code09_MaxHappy.java

@@ -1,4 +1,4 @@
-package class08;
+package class08_12;
 
 import java.util.ArrayList;
 import java.util.List;