leetle

38. Balanced Binary Tree

Write a function solve that checks if a binary tree is height-balanced. A height-balanced binary tree is defined as a binary tree in which the left and right subtrees of every node differ in height by no more than 1.

Example: Input: [3,9,20,None,None,15,7] Output: True

Make sure you return your solution, don't print!

Python3

def solve(root):
    pass

Binary Tree Definition

class TreeNode:
    def __init__(self, val=0, left=None, right=None):
        self.val = val
        self.left = left
        self.right = right