判断一个二叉树是不是完全二叉树
作者:互联网
import java.util.LinkedList;
import java.util.Queue;
/**
* 判断一个二叉树是不是完全二叉树
*/
public class CompleteBinaryTree {
public static void main(String[] args) {
BinaryTreeNode node1 = new BinaryTreeNode(1);
BinaryTreeNode node2 = new BinaryTreeNode(2);
BinaryTreeNode node3 = new BinaryTreeNode(3);
BinaryTreeNode node4 = new BinaryTreeNode(4);
BinaryTreeNode node5 = new BinaryTreeNode(5);
BinaryTreeNode node6 = new BinaryTreeNode(6);
BinaryTreeNode node7 = new BinaryTreeNode(7);
BinaryTreeNode node8 = new BinaryTreeNode(8);
BinaryTreeNode node9 = new BinaryTreeNode(9);
node1.left = node2;
node1.right = node3;
node2.left = node4;
node2.right = node7;
node3.left = node8;
System.out.println(Complete(node1));
}
public static boolean Complete(BinaryTreeNode root){
if (root == null){
return true;
}
Queue<BinaryTreeNode> queue = new LinkedList<>();
BinaryTreeNode left = null;
BinaryTreeNode right = null;
boolean leaf = false; //判断有没有出现叶子节点
queue.add(root);
while (!queue.isEmpty()){
root = queue.poll();
left = root.left;
right = root.right;
if ((left == null && right != null) || (leaf && (left != null || right != null))){
return false;
}
if (left != null){
queue.add(left);
}
if (right != null){
queue.add(right);
}
if (left == null || right == null){
leaf = true;
}
}
return true;
}
}
标签:判断,是不是,queue,BinaryTreeNode,right,二叉树,new,null,left 来源: https://www.cnblogs.com/codegzy/p/15427020.html