[leetcode/java] 226. Invert Binary Tree

 

class Solution {
    public TreeNode invertTree(TreeNode root) {
        if (root == null) return root;
                
        TreeNode node = root.left;
        root.left = root.right;
        root.right = node;
        
        invertTree(root.left);
        invertTree(root.right);
        
        return root;
    }
}