Sword finger offer 27. image of binary tree

Title Description

Problem analysis

Ontology uses queues to do , The purpose of the queue is to store the binary tree of the original sequence order
First, determine whether the root node is empty
Then create a new sub queue
The queue is pushed into the root node
Use while（ loop ）
Pop up queue elements
Press in the left and right nodes respectively
Switch left and right nodes
Return to the initial node

Code instance

class Solution {
    
    public TreeNode mirrorTree(TreeNode pRoot) {
    
        if(pRoot == null){
    
            return null;
        }
        Queue<TreeNode> que = new LinkedList<>();
        que.offer(pRoot);
        while(!que.isEmpty()){
    
            TreeNode temp = que.poll();
            if(temp.left != null){
    
                que.offer(temp.left);
            }
            if(temp.right != null){
    
                que.offer(temp.right);
            }
            TreeNode tem = temp.left;
            temp.left = temp.right;
            temp.right = tem;
        }
        return pRoot;
    }
}