<?xml version="1.0" encoding="utf-8" ?><rss version="2.0"><channel><title><![CDATA[Mereder的博客]]></title><description><![CDATA[学习积累]]></description><link>https://blog.youkuaiyun.com/xushibi4580</link><language>zh-cn</language><generator>https://blog.youkuaiyun.com/</generator><copyright><![CDATA[Copyright &copy; xushibi4580]]></copyright><item><title><![CDATA[使用pip install 之后pip消失 ModuleNotFoundError: No module named 'pip']]></title><link>https://blog.youkuaiyun.com/xushibi4580/article/details/99498819</link><guid>https://blog.youkuaiyun.com/xushibi4580/article/details/99498819</guid><author>xushibi4580</author><pubDate>Tue, 13 Aug 2019 20:47:00 +0800</pubDate><description><![CDATA[背景：

在安装torch的时候，pip install torch 然后安装失败，告诉我需要更新我的pip，于是我更新了自己的pip，就是常规操作：pip install --upgrade pip,更新居然失败了。很神奇，那就再尝试一次吧。然后更神奇居然直接==找不到pip了：ModuleNotFoundError: No module named '...]]></description><category></category></item><item><title><![CDATA[剑指Offer——表示数值的字符串 Java]]></title><link>https://blog.youkuaiyun.com/xushibi4580/article/details/90347962</link><guid>https://blog.youkuaiyun.com/xushibi4580/article/details/90347962</guid><author>xushibi4580</author><pubDate>Mon, 20 May 2019 22:39:14 +0800</pubDate><description><![CDATA[题目描述
请实现一个函数用来判断字符串是否表示数值（包括整数和小数）。例如，字符串"+100",“5e2”,"-123",“3.1416"和”-1E-16"都表示数值。 但是"12e",“1a3.14”,“1.2.3”,"±5"和"12e+4.3"都不是。
解题思路
对思考的完备性：
最复杂的   “+123.123e+123”
先确定有无正负号，然后判断是否是个整数，当非数字字符时候 再判断是否...]]></description><category></category></item><item><title><![CDATA[Leetcode 437 Path Sum III]]></title><link>https://blog.youkuaiyun.com/xushibi4580/article/details/90387503</link><guid>https://blog.youkuaiyun.com/xushibi4580/article/details/90387503</guid><author>xushibi4580</author><pubDate>Mon, 20 May 2019 22:32:00 +0800</pubDate><description><![CDATA[题目链接：437. Path Sum III
题目描述
You are given a binary tree in which each node contains an integer value.
Find the number of paths that sum to a given value.
The path does not need to...]]></description><category></category></item><item><title><![CDATA[Leetcode 113 Path Sum II]]></title><link>https://blog.youkuaiyun.com/xushibi4580/article/details/90387500</link><guid>https://blog.youkuaiyun.com/xushibi4580/article/details/90387500</guid><author>xushibi4580</author><pubDate>Mon, 20 May 2019 21:02:00 +0800</pubDate><description><![CDATA[题目链接：113. Path Sum II
题目描述
Given a binary tree and a sum, find all root-to-leaf paths where each path's sum equals the given sum.
Note: A leaf is a node with no children.
简而言之，就是在...]]></description><category></category></item><item><title><![CDATA[Leetcode 112 PathSum]]></title><link>https://blog.youkuaiyun.com/xushibi4580/article/details/90387901</link><guid>https://blog.youkuaiyun.com/xushibi4580/article/details/90387901</guid><author>xushibi4580</author><pubDate>Mon, 20 May 2019 20:56:00 +0800</pubDate><description><![CDATA[题目链接：112. Path Sum
题目描述
Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals the given sum.
Note: ...]]></description><category></category></item><item><title><![CDATA[剑指Offer——二叉树的下一个结点]]></title><link>https://blog.youkuaiyun.com/xushibi4580/article/details/90387499</link><guid>https://blog.youkuaiyun.com/xushibi4580/article/details/90387499</guid><author>xushibi4580</author><pubDate>Mon, 20 May 2019 20:49:00 +0800</pubDate><description><![CDATA[题目描述
给定一个二叉树和其中的一个结点，请找出中序遍历顺序的下一个结点并且返回。注意，树中的结点不仅包含左右子结点，同时包含指向父结点的指针。
（实际题目给的是二叉树中的一个结点，给出该结点的下一个结点）
解题思路
一棵树中，给定其中的一个结点，我们分别分析下，在中序遍历条件下，该结点的下一个结点在哪：
（建议大家画图理解下）
因为是中序遍历，该结点的左...]]></description><category></category></item><item><title><![CDATA[将博客搬至优快云]]></title><link>https://blog.youkuaiyun.com/xushibi4580/article/details/90354529</link><guid>https://blog.youkuaiyun.com/xushibi4580/article/details/90354529</guid><author>xushibi4580</author><pubDate>Sun, 19 May 2019 21:20:00 +0800</pubDate><description><![CDATA[test

          
  

]]></description><category></category></item><item><title><![CDATA[快速排序的总结和优化]]></title><link>https://blog.youkuaiyun.com/xushibi4580/article/details/90347797</link><guid>https://blog.youkuaiyun.com/xushibi4580/article/details/90347797</guid><author>xushibi4580</author><pubDate>Sun, 19 May 2019 21:14:01 +0800</pubDate><description><![CDATA[快排的基本框架就是下边这样。更鲁棒一点的话，还需要考虑传入的array是否是非法参数。
此处优化：应当将数组，打乱顺序，如果数组基本有序，快排的时间复杂度将退化到O(n2)O(n^2 )O(n2)
应该在传入sort之前就将数组 shuffle。
public static void sort(int[] array,int lo ,int hi){
    if (array == null |...]]></description><category></category></item><item><title><![CDATA[剑指Offer——字符串的旋转]]></title><link>https://blog.youkuaiyun.com/xushibi4580/article/details/90354526</link><guid>https://blog.youkuaiyun.com/xushibi4580/article/details/90354526</guid><author>xushibi4580</author><pubDate>Sun, 19 May 2019 20:51:00 +0800</pubDate><description><![CDATA[问题一：左旋转字符串
题目描述
汇编语言中有一种移位指令叫做循环左移（ROL），现在有个简单的任务，就是用字符串模拟这个指令的运算结果。对于一个给定的字符序列S，请你把其循环左移K位后的序列输出。例如，字符序列S=”abcXYZdef”,要求输出循环左移3位后的结果，即“XYZdefabc”。是不是很简单？OK，搞定它！
解题思路
如果没有看《剑指》，自己...]]></description><category></category></item><item><title><![CDATA[Python 函数的参数传递*args和**kwargs]]></title><link>https://blog.youkuaiyun.com/xushibi4580/article/details/90173803</link><guid>https://blog.youkuaiyun.com/xushibi4580/article/details/90173803</guid><author>xushibi4580</author><pubDate>Mon, 13 May 2019 15:09:45 +0800</pubDate><description><![CDATA[参数传递机制具有值传递（int、float等值数据类型）和引用传递（以字典、列表等非值对象数据类型为代表）两种基本机制。
值传递，应用的参数不发生更改。（传了个副本进去）
a = 5
print(a)
def test(a):
    a+=1
    print("函数内：%d" % a)
test(a)
print(a)
​```output
5
函数内：6
5
​```

引用传递，引用的参...]]></description><category></category></item><item><title><![CDATA[Python 函数的参数传递\*args和\**kwargs]]></title><link>https://blog.youkuaiyun.com/xushibi4580/article/details/90354524</link><guid>https://blog.youkuaiyun.com/xushibi4580/article/details/90354524</guid><author>xushibi4580</author><pubDate>Mon, 13 May 2019 15:07:00 +0800</pubDate><description><![CDATA[Python 函数的参数传递*args和**kwargs
参数传递机制具有值传递（int、float等值数据类型）和引用传递（以字典、列表等非值对象数据类型为代表）两种基本机制。
值传递，应用的参数不发生更改。（传了个副本进去）
a = 5
print(a)
def test(a):
    a+=1
    print("函数内：%d" % a)
tes...]]></description><category></category></item><item><title><![CDATA[动态规划总结——通过例题疏通你]]></title><link>https://blog.youkuaiyun.com/xushibi4580/article/details/90113947</link><guid>https://blog.youkuaiyun.com/xushibi4580/article/details/90113947</guid><author>xushibi4580</author><pubDate>Sat, 11 May 2019 20:08:04 +0800</pubDate><description><![CDATA[动态规划
多阶段决策的过程：每一步求解的问题是后面阶段求解问题的子问题，每一步决策都将依赖于以前决策的结果
优化函数值之间存在依赖关系
优化函数的特点：任何最短路的子路径相对于子问题始、终点最短
一定要存在依赖关系！
一定要满足优化原则或最优子结构性质
设计要素
多阶段决策过程，每步处理一个子问题，界定子问题的边界
列出优化函数的递推方程以及初值
问题满足优化原则或最优子结构性质。一个最优决策序列...]]></description><category></category></item><item><title><![CDATA[Leetcode 96 Unique Binary Search Trees]]></title><link>https://blog.youkuaiyun.com/xushibi4580/article/details/90354522</link><guid>https://blog.youkuaiyun.com/xushibi4580/article/details/90354522</guid><author>xushibi4580</author><pubDate>Sat, 11 May 2019 19:38:00 +0800</pubDate><description><![CDATA[题目链接：96. Unique Binary Search Trees
题目描述
Given n, how many structurally unique BST's (binary search trees) that store values 1 ... n?
简而言之：给定1...n这N个数，问有多少种构造BST的方案。
Example:
Inpu...]]></description><category></category></item><item><title><![CDATA[Leetcode 343 Integer Break]]></title><link>https://blog.youkuaiyun.com/xushibi4580/article/details/90354521</link><guid>https://blog.youkuaiyun.com/xushibi4580/article/details/90354521</guid><author>xushibi4580</author><pubDate>Sat, 11 May 2019 19:36:00 +0800</pubDate><description><![CDATA[题目描述
Given a positive integer n, break it into the sum of at least two positive integers and maximize the product of those integers. Return the maximum product you can get.
Exampl...]]></description><category></category></item><item><title><![CDATA[Leetcode 136 Single Number]]></title><link>https://blog.youkuaiyun.com/xushibi4580/article/details/90354519</link><guid>https://blog.youkuaiyun.com/xushibi4580/article/details/90354519</guid><author>xushibi4580</author><pubDate>Sat, 11 May 2019 19:09:00 +0800</pubDate><description><![CDATA[题目链接：136. Single Number
题目描述
Given a non-empty array of integers, every element appears twice except for one. Find that single one.
Note:
Your algorithm should have a linear runti...]]></description><category></category></item><item><title><![CDATA[Leetcode 412 Fizz Buzz]]></title><link>https://blog.youkuaiyun.com/xushibi4580/article/details/90354517</link><guid>https://blog.youkuaiyun.com/xushibi4580/article/details/90354517</guid><author>xushibi4580</author><pubDate>Sat, 11 May 2019 09:50:00 +0800</pubDate><description><![CDATA[题目链接：412. Fizz Buzz
题目描述
Write a program that outputs the string representation of numbers from 1 to n.
But for multiples of three it should output “Fizz” instead of the number an...]]></description><category></category></item><item><title><![CDATA[Leetcode 287 Find the Duplicate Number]]></title><link>https://blog.youkuaiyun.com/xushibi4580/article/details/90354515</link><guid>https://blog.youkuaiyun.com/xushibi4580/article/details/90354515</guid><author>xushibi4580</author><pubDate>Sat, 11 May 2019 09:36:00 +0800</pubDate><description><![CDATA[题目链接：Find the Duplicate Number
题目描述
Given an array nums containing n + 1 integers where each integer is between 1 and n (inclusive), prove that at least one duplicate number must ...]]></description><category></category></item><item><title><![CDATA[剑指Offer——链表的环以及环的入口]]></title><link>https://blog.youkuaiyun.com/xushibi4580/article/details/90354514</link><guid>https://blog.youkuaiyun.com/xushibi4580/article/details/90354514</guid><author>xushibi4580</author><pubDate>Sat, 11 May 2019 09:34:00 +0800</pubDate><description><![CDATA[题目描述
在一个排序的链表中，存在重复的结点，请删除该链表中重复的结点，重复的结点不保留，返回链表头指针。 例如，链表1-&gt;2-&gt;3-&gt;3-&gt;4-&gt;4-&gt;5 处理后为 1-&gt;2-&gt;5
解题思路
这个题包含两个子问题，一个是判断链表是否有环，另一个是如果有环，找到环的入口。

对于如何判断链表有环问题，较为基础...]]></description><category></category></item><item><title><![CDATA[Leetcode 701 Insert into a Binary Search Tree]]></title><link>https://blog.youkuaiyun.com/xushibi4580/article/details/90354511</link><guid>https://blog.youkuaiyun.com/xushibi4580/article/details/90354511</guid><author>xushibi4580</author><pubDate>Fri, 10 May 2019 16:37:00 +0800</pubDate><description><![CDATA[题目链接：701. Insert into a Binary Search Tree
题目描述
Given the root node of a binary search tree (BST) and a value to be inserted into the tree, insert the value into the BST. Return t...]]></description><category></category></item><item><title><![CDATA[Leetcode 98 Validate Binary Search Tree]]></title><link>https://blog.youkuaiyun.com/xushibi4580/article/details/90354507</link><guid>https://blog.youkuaiyun.com/xushibi4580/article/details/90354507</guid><author>xushibi4580</author><pubDate>Fri, 10 May 2019 16:20:00 +0800</pubDate><description><![CDATA[题目链接：98. Validate Binary Search Tree
题目描述
Given a binary tree, determine if it is a valid binary search tree (BST).
Assume a BST is defined as follows:

The left subtree of a node...]]></description><category></category></item></channel></rss>