Invert Binary Tree

1. Problem Description

Invert a binary tree.

2. Approach

1. Approach 1
   • Preorder traversal
   • Swap the left and right subtrees
   • Apply the same operation recursively to the left and right subtrees

3. Implementation

/**
 * Definition for a binary tree node.
 * type TreeNode struct {
 *     Val int
 *     Left *TreeNode
 *     Right *TreeNode
 * }
 */
func invertTree(root *TreeNode) *TreeNode {
    if root == nil {
        return nil
    }

    root.Left, root.Right = root.Right, root.Left
    invertTree(root.Left)
    invertTree(root.Right)
    return root
}

4. References

• 226. Invert Binary Tree - LeetCode