求二叉樹的深度，前序遍歷，中序遍歷，後序遍歷，節點個數，是否為空，查詢某一個節點，測試方式
阿新 • • 發佈：2018-11-28
package com.bjsxt.tree; import java.util.ArrayList; import java.util.Deque; import java.util.LinkedList; import java.util.Queue; /** * * @author Administrator * */ public class BinaryTree implements BinaryInterface{ Node root; public Node getRoot() { return root; } public void setRoot(Node root) { this.root = root; } public BinaryTree(Node root) { super(); this.root = root; } public BinaryTree() { super(); // TODO Auto-generated constructor stub } @Override public boolean isEmpty() { return root==null; } @Override public int size() { if(root==null) { return 0; }else if(root.leftChild==null&&root.rightChild==null) { return 1; }else { BinaryTree lefttree=new BinaryTree(root.leftChild); BinaryTree righttree=new BinaryTree(root.rightChild); int i=lefttree.size(); int j=righttree.size(); return i+j+1; } } @Override public int getheight() { return this.getHeight(root); } private int getHeight(Node root) { if(root==null) { return 0; }else if(root.leftChild==null&&root.rightChild==null) { return 1; } else { int i=this.getHeight(root.leftChild); int j=this.getHeight(root.rightChild); return (i<j)?(i+1):(j+1); } } @Override public Node findKey(int value) { return findKey(value,root); } private Node findKey(int value, Node root2) { if(root==null) { return null; }else if(root!=null&&root.value==value) { return root; }else { Node node1=this.findKey(value, root2.leftChild); Node node2=this.findKey(value, root2.rightChild); if(node1!=null&&node1.value==value) { return node1; }else if(node2!=null&&node2.value==value) { return node2; }else { return null; } } } @Override public void preOrderTraverse() { // System.out.println("前序遍歷"); if(root!=null) { System.out.println(root.value+""); if(root.leftChild!=null) { BinaryTree lefttree=new BinaryTree(root.leftChild); lefttree.preOrderTraverse(); } if(root.rightChild!=null) { BinaryTree righttree=new BinaryTree(root.rightChild); righttree.preOrderTraverse(); } } } @Override public void midOrderTraverse() { System.out.println("中序遞迴遍歷二叉樹"); this.MidOrderTraverse(root); } private void MidOrderTraverse(Node root2) { this.MidOrderTraverse(root.leftChild); System.out.println(root.value); this.MidOrderTraverse(root2.rightChild); } @Override public void postOrderTraverse() { System.out.println("後序遞迴遍歷二叉樹"); this.postOrderTraverse(root); System.out.println(); } private void postOrderTraverse(Node node) { if(root!=null) { this.postOrderTraverse(node.leftChild); this.postOrderTraverse(node.rightChild); System.out.println(node.value+" "); }else { System.out.println("zhiweikong"); } } //中序遍歷非遞迴 @Override public void inOrderByStack() { System.out.println("中序遍歷非遞迴操作"); //建立棧 Deque<Node> stack=new LinkedList<Node>(); Node current=root; while(current!=null||!stack.isEmpty()) { while(current!=null) { stack.push(current); current=current.leftChild; } if(!stack.isEmpty()) { current=stack.pop(); System.out.println(current.value+""); current=current.rightChild; } } System.out.println(); } //中序遍歷二叉樹 @Override public void preOrderByStack() { System.out.println("中序遍歷二叉樹非遞迴操作"); //建立棧 Deque<Node> stack=new LinkedList<Node>(); Node current=root; while(current!=null||!stack.isEmpty()) { while(current!=null) { stack.push(current); current=current.leftChild; } if(!stack.isEmpty()) { current=stack.pop(); System.out.println(current.value+""); current=current.rightChild; } } } @Override public void levelOrderByStack() { if(root==null) { return; } //建立佇列 Queue<Node> queue=new LinkedList<Node>(); queue.add(root); while(queue.size()!=0) { int len=queue.size(); for(int i=0;i<len;i++) { Node tmp=queue.poll(); System.out.println(tmp.value); if(tmp.leftChild!=null) { queue.add(tmp.leftChild); } if(tmp.rightChild!=null) { queue.add(tmp.rightChild); } } } } @Override public void postOrderByStack() { } public int getwidth(Node root) { if(root==null) { return 0; } Queue<Node> queue=new LinkedList<Node>(); int maxWidth=1; queue.add(root); while(true) { int len=queue.size(); if(len==0) break; while(len>0) { Node node=queue.poll(); len--; if(node.leftChild!=null) queue.add(node.leftChild); if(node.rightChild!=null) queue.add(node.rightChild); } maxWidth=Math.max(maxWidth, queue.size()); } return maxWidth; } //獲取二叉樹中葉子結點的個數： public int getLeave(Node root) { int count=0; if(root==null) return 0; if(root.leftChild!=null) getLeave(root.leftChild); if(root.rightChild!=null) getLeave(root.rightChild); if(root.leftChild==null&&root.rightChild==null) count++; return count; } //獲取二叉樹的最大寬度 public int getWidth(Node root) { int maxWith=1; if(root==null) { return 0; }else if(root.leftChild==null&&root.rightChild==null) { return 1; }else { Queue<Node> queue=new LinkedList<Node>(); maxWith=1; queue.add(root); while(true) { int len=queue.size(); if(len==0) { break; }else { while(len>0) { Node node=queue.poll(); len--; if(node.leftChild!=null) { queue.add(node.leftChild); }else if(node.rightChild!=null) { queue.add(node.rightChild); } } } } maxWith=Math.max(maxWith, queue.size()); } return maxWith; } }
測試方式：
package com.bjsxt.tree; public class Test { public static void main(String[] args) { Node node5=new Node(5,null,null); Node node4=new Node(4,null,node5); Node node7=new Node(7,null,null); Node node3=new Node(3,null,null); Node node6=new Node(6,null,node7); Node node2=new Node(2,node3,node6); Node node1=new Node(1,node4,node2); BinaryTree btree=new BinaryTree(node1); // System.out.println(btree.size()); // System.out.println(btree.isEmpty()); // System.out.println(btree.getheight()); // btree.preOrderTraverse(); // btree.midOrderTraverse(); // btree.postOrderTraverse(); // btree.preOrderByStack(); //// btree.findKey(4); // btree.inOrderByStack(); // System.out.println(btree.getwidth(node1)); System.out.println(btree.getLeave(node1)); } }
原圖在這裡~
