package Leetcode.Trees;

/**
 * @author zhengstars
 * @date 2024/03/31
 */
public class InvertBinaryTree {

    // Function to invert a binary tree
    public static  TreeNode invertTree(TreeNode root) {
        // Base case: if the tree is empty, return null
        if(root == null){
            return null;
        }

        // Swap the left and right child of each node
        TreeNode temp = root.left;
        root.left = root.right;
        root.right = temp;

        // Recursively invert the left and right subtree
        invertTree(root.left);
        invertTree(root.right);

        // Return the root of the inverted tree
        return root;
    }

    public static void main(String[] args) {
        // Construct a binary tree
        TreeNode root1 = new TreeNode(4);
        root1.left = new TreeNode(2);
        root1.right = new TreeNode(7);
        root1.left.left = new TreeNode(1);
        root1.left.right = new TreeNode(3);
        root1.right.left = new TreeNode(6);
        root1.right.right = new TreeNode(9);

        // Invert the binary tree
        TreeNode invertedRoot1 = invertTree(root1);
    }
}