226. Invert Binary Tree

Given the root of a binary tree, invert the tree, and return its root.

 

Example :




def invertTree(root: Optional[TreeNode]):
               
    def recurse(n):
       
        if n is None:
            return
       
        l = recurse(n.left)
        r = recurse(n.right)
       
        n.left = r
        n.right = l
       
        return n
   
    return recurse(root)
           

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