Invert Binary Tree

Statement

Given the root node of a binary tree, transform the tree by swapping each node’s left and right subtrees, thus creating a mirror image of the original tree. Return the root of the transformed tree.

Constraints:

• $0\leq$ Number of nodes in the tree $\leq 100$
• $-1000 \leq$ Node.value $\leq 1000$

Examples