摘要：
https://leetcode.com/problems/diameter-of-binary-tree/ 1.一次就写出来了，因为和一个前面做的一个题目很像 阅读全文
摘要：
Runtime: 44 ms, faster than 94.63% of Python3 online submissions for Sort Characters By Frequency. 1.有两个函数使用不熟练，一个是Counter(list),另一个是most_comon函数。具体解释 阅读全文
摘要：
# Definition for a binary tree node.# class TreeNode:# def __init__(self, x):# self.val = x# self.left = None# self.right = None class Solution: def f 阅读全文
摘要：
https://leetcode.com/problems/kth-largest-element-in-a-stream/ 这个题目的意思解读了半天，没搞明白什么意思，后来画了一下图，一下子就明了 1.熟悉了一下怎么使用heapqd的常规函数 2.最后这个 阅读全文
摘要：
https://leetcode.com/problems/network-delay-time/ Runtime: 152 ms, faster than 83.77% of Python3 online submissions forNetwork Delay Time. 优秀的结题报告，提供了 阅读全文
摘要：
A Data Science Framework: To Achieve 99% Accuracy https://www.kaggle.com/ldfreeman3/a-data-science-framework-to-achieve-99-accuracy/notebook 额，总共花了2天时 阅读全文
摘要：
Runtime: 36 ms, faster than 52.18% of Python online submissions for Univalued Binary Tree. Runtime: 32 ms, faster than 97.16% of Python online submiss 阅读全文
摘要：
https://leetcode.com/problems/unique-email-addresses/ 熟悉使用string的相关操作即可 Runtime: 60 ms, faster than 58.66% of Python online submissions for Unique Ema 阅读全文