python判断平衡二叉树
题目:输入一棵二叉树,判断该二叉树是否是平衡二叉树。若左右子树深度差不超过1则为一颗平衡二叉树。
思路:
- 使用获取二叉树深度的方法来获取左右子树的深度
- 左右深度相减,若大于1返回False
- 通过递归对每个节点进行判断,若全部均未返回False,则返回True
class TreeNode(): def __init__(self,x): self.val = x self.left = None self.right = None class Solution: def getDeepth(self,Root): if Root is None: return 0 nright = self.getDeepth(Root.right) nleft = self.getDeepth(Root.left) return max(nright,nleft)+1 def IsBalance_solution(self,pRoot): if pRoot is None: return True right = self.getDeepth(pRoot.right) left = self.getDeepth(pRoot.left) if abs(right - left) > 1: return False return self.IsBalance_solution(pRoot.right) and self.IsBalance_solution(pRoot.left)