Leetcode #530 Minimum Absolute Difference in BST

Description

Given a binary search tree with non-negative values, find the minimum absolute difference between values of any two nodes.

Example

Input:

1

\

3

/

2

Output:

1

Explanation:

The minimum absolute difference is 1, which is the difference between 2 and 1 (or between 2 and 3).

Explain

将节点的值都放数组里sort一下然后遍历一遍

Code

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

class Solution(object):
def getMinimumDifference(self, root):
"""
:type root: TreeNode
:rtype: int
"""
minn = 1e10
res = []
node = []
if root:
node.append(root)
while node:
top = node.pop()
res.append(top.val)
if top.left:
node.append(top.left)
if top.right:
node.append(top.right)
res.sort()
res_len = len(res)
for i in range(0, res_len-1):
minn = min(minn, abs(res[i]-res[i+1]))
return minn