# [Solved] Given a binary tree, determine if it is height-balanced. For this problem, 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.

Table of Contents

## Question

Given a binary tree, determine if it is height-balanced.

For this problem, 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 1:

```Input: root = [3,9,20,null,null,15,7]
Output: true
```

Example 2:

```Input: root = [1,2,2,3,3,null,null,4,4]
Output: false
```

Example 3:

```Input: root = []
Output: true
```

Constraints:

• The number of nodes in the tree is in the range `[0, 5000]`.
• `-104 <= Node.val <= 104`

## Python Solution

```# Definition for a binary tree node.
# class TreeNode:
#     def __init__(self, val=0, left=None, right=None):
#         self.val = val
#         self.left = left
#         self.right = right

def height(root):
global isBal
if not root: return 0
lh = height(root.left)
rh = height(root.right)
if abs(lh-rh)>1:isBal= False
return 1+max(lh,rh)

class Solution:
def isBalanced(self, root: TreeNode) -> bool:
global isBal
isBal = True
height(root)
return isBal```