104_maxDepth.py

#!/usr/bin/python
# -*- coding: utf-8 -*-

# Author: Yu Zhou

# ****************
# Descrption:
# Given a binary tree, find its maximum depth.
# ****************

# 思路：
# 基础题，确保有Root就行。然后递归

# ****************
# Final Solution *
# ****************
classSolution(object):
defmaxDepth(self, root):
ifnotroot:
return0
else:
returnmax(self.maxDepth(root.left), self.maxDepth(root.right)) +1


# ********************
# Divide and Conquer *
# ******************** 
classSolution(object):
defmaxDepth(self, root):
ifnotroot:
return0
else:
# using Divide and Conquer
left=self.maxDepth(root.left)
right=self.maxDepth(root.right)
returnmax(left, right) +1