<?xml version="1.0" encoding="utf-8" ?><rss version="2.0"><channel><title><![CDATA[qq_41007874的博客]]></title><description><![CDATA[]]></description><link>https://blog.youkuaiyun.com/qq_41007874</link><language>zh-cn</language><generator>https://blog.youkuaiyun.com/</generator><copyright><![CDATA[Copyright &copy; qq_41007874]]></copyright><item><title><![CDATA[git提交代码【自留】]]></title><link>https://blog.youkuaiyun.com/qq_41007874/article/details/125261546</link><guid>https://blog.youkuaiyun.com/qq_41007874/article/details/125261546</guid><author>qq_41007874</author><pubDate>Mon, 13 Jun 2022 16:34:10 +0800</pubDate><description><![CDATA[git自用]]></description><category></category></item><item><title><![CDATA[Linux搭MongoDB分片键]]></title><link>https://blog.youkuaiyun.com/qq_41007874/article/details/125188898</link><guid>https://blog.youkuaiyun.com/qq_41007874/article/details/125188898</guid><author>qq_41007874</author><pubDate>Wed, 08 Jun 2022 17:30:07 +0800</pubDate><description><![CDATA[linux搭建MongoDB分片集]]></description><category></category></item><item><title><![CDATA[win10下mongo分片搭建]]></title><link>https://blog.youkuaiyun.com/qq_41007874/article/details/125147436</link><guid>https://blog.youkuaiyun.com/qq_41007874/article/details/125147436</guid><author>qq_41007874</author><pubDate>Mon, 06 Jun 2022 15:55:15 +0800</pubDate><description><![CDATA[分片]]></description><category></category></item><item><title><![CDATA[Win10 在本机搭建mongo副本集]]></title><link>https://blog.youkuaiyun.com/qq_41007874/article/details/125087870</link><guid>https://blog.youkuaiyun.com/qq_41007874/article/details/125087870</guid><author>qq_41007874</author><pubDate>Thu, 02 Jun 2022 13:22:08 +0800</pubDate><description><![CDATA[mongo副本集]]></description><category></category></item><item><title><![CDATA[Springboot+MongoDB]]></title><link>https://blog.youkuaiyun.com/qq_41007874/article/details/124624416</link><guid>https://blog.youkuaiyun.com/qq_41007874/article/details/124624416</guid><author>qq_41007874</author><pubDate>Mon, 16 May 2022 16:04:01 +0800</pubDate><description><![CDATA[概述：可以使用MongoTemplate或继承MongoRepository接口

1. MongoRepository接口

若继承MongoRepository接口可以实现简单的增删改查操作，不用写相应的dao层代码


// MongoRepository&lt;T, ID&gt; T为实体类，ID为主键ID
public interface StdRepository extends MongoRepository&lt;StdDto,Long&gt; {
}





2. MongoTempla]]></description><category></category></item><item><title><![CDATA[JSONObject]]></title><link>https://blog.youkuaiyun.com/qq_41007874/article/details/124799506</link><guid>https://blog.youkuaiyun.com/qq_41007874/article/details/124799506</guid><author>qq_41007874</author><pubDate>Mon, 16 May 2022 15:55:21 +0800</pubDate><description><![CDATA[JSONObject只是一种数据结构，是key-value格式

1.导入依赖


&lt;dependency&gt;
    &lt;groupId&gt;com.alibaba&lt;/groupId&gt;
    &lt;artifactId&gt;fastjson&lt;/artifactId&gt;
    &lt;version&gt;1.2.75&lt;/version&gt;
&lt;/dependency&gt;

2.创建

2.1 直接创建


JSONObject obj = n]]></description><category></category></item><item><title><![CDATA[Java反射]]></title><link>https://blog.youkuaiyun.com/qq_41007874/article/details/124794894</link><guid>https://blog.youkuaiyun.com/qq_41007874/article/details/124794894</guid><author>qq_41007874</author><pubDate>Mon, 16 May 2022 13:49:57 +0800</pubDate><description><![CDATA[能够分析类能力的程序成为反射，反射机制可以用来：

在运行时分析类的能力
	在运行时检查对象
	实现泛型数组操作代码
	利用Method对象
1. Class类

在程序运行期间，Java运行时系统始终为所有对象维护一个运行时类型标识。这个信息会跟踪每个对象所属的类。虚拟机利用运行时类型信息选择要执行的正确的方法。可以使用一个特殊的Java类访问这些信息。保存这些信息的类型为Class，Object类中的getClass()方法将会返回一个Class类型的实例。

获取Class对象的三种方...]]></description><category></category></item><item><title><![CDATA[MongoDB查询]]></title><link>https://blog.youkuaiyun.com/qq_41007874/article/details/124629034</link><guid>https://blog.youkuaiyun.com/qq_41007874/article/details/124629034</guid><author>qq_41007874</author><pubDate>Sat, 07 May 2022 14:28:17 +0800</pubDate><description><![CDATA[Person表结构如下图所示

         

1. 查询全部

sql


select * from person;

mongodb


db.person.find()

2. 只显示name和age字段

sql


select name,age from person;

mongodb


db.person.find({},{name:1,age:1,_id:0})

_id默认显示，若不想显示_id则需标注成0，其他字段默认不显示



3. 查询姓名是"To......]]></description><category></category></item><item><title><![CDATA[LeetCode（5）Longest Palindromic Substring最长回文子串]]></title><link>https://blog.youkuaiyun.com/qq_41007874/article/details/118786749</link><guid>https://blog.youkuaiyun.com/qq_41007874/article/details/118786749</guid><author>qq_41007874</author><pubDate>Fri, 16 Jul 2021 11:10:11 +0800</pubDate><description><![CDATA[输出S中的最长回文串

eg.


Input: s = "babad"
Output: "bab"

Approach 1

纯暴力匹配，提交超时

Approcah 2 Manacher算法

将暴力匹配的算法复杂度提升到O(n)，先对S进行处理，每个字符前后插入"#"(或其他S内不可能出现的字符)，经过处理的S'长度一定为奇数，分别以每一个字符为中心计算他的回文半径len，原字符串中它的回文长度为len-1，所以问题变为求每一个字符的len[i]。

p:最右回文边界

center：当前p的中心
.]]></description><category></category></item><item><title><![CDATA[Dynamic Programming动态规划]]></title><link>https://blog.youkuaiyun.com/qq_41007874/article/details/118328188</link><guid>https://blog.youkuaiyun.com/qq_41007874/article/details/118328188</guid><author>qq_41007874</author><pubDate>Tue, 29 Jun 2021 14:10:25 +0800</pubDate><description><![CDATA[1、介绍

    动态规划是通过组合子问题的解而解决整个问题，动态规划适用于子问题不是独立的情况，也就是各子问题包含公共的子子问题。动态规划算法对每个子子问题只求解一次，将其结果保存在一张表中，从而避免每次遇到各个子问题时重新计算。

    动态规划通常应用于最优化问题，此类问题可能有很多种可行解。每个解有一个值，而我们希望找出一个具有最优（最大或最小）值的解。称这样的解为该问题的“一个”最优解（而不是“确定”的“最优解”），因为可能存在多个取最优值的解。

    动态规划算法...]]></description><category></category></item><item><title><![CDATA[LeetCode(66)Plus One]]></title><link>https://blog.youkuaiyun.com/qq_41007874/article/details/117777208</link><guid>https://blog.youkuaiyun.com/qq_41007874/article/details/117777208</guid><author>qq_41007874</author><pubDate>Thu, 10 Jun 2021 14:37:42 +0800</pubDate><description><![CDATA[题目：

Given anon-emptyarray of decimal digitsrepresenting a non-negative integer, incrementone to the integer.

The digits are stored such that the most significant digit is at the head of the list, and each element in the array contains a single digit....]]></description><category></category></item><item><title><![CDATA[LeetCode(53)Maximum Subarray]]></title><link>https://blog.youkuaiyun.com/qq_41007874/article/details/117668876</link><guid>https://blog.youkuaiyun.com/qq_41007874/article/details/117668876</guid><author>qq_41007874</author><pubDate>Mon, 07 Jun 2021 17:37:33 +0800</pubDate><description><![CDATA[题目：

Given an integer arraynums, find the contiguous subarray (containing at least one number) which has the largest sum and returnits sum.

思路：

返回由相邻数组相加得到的最大的和


class Solution {
    public int maxSubArray(int[] nums) {
        int sum = nums[0];
		in..]]></description><category></category></item><item><title><![CDATA[LeetCode（21） Merge Two Sorted Lists]]></title><link>https://blog.youkuaiyun.com/qq_41007874/article/details/117459968</link><guid>https://blog.youkuaiyun.com/qq_41007874/article/details/117459968</guid><author>qq_41007874</author><pubDate>Wed, 02 Jun 2021 09:46:39 +0800</pubDate><description><![CDATA[题目：

Merge two sorted linked lists and return it as asortedlist. The list should be made by splicing together the nodes of the first two lists.



将两个ListNode按照顺序拼接成一个，一开始想通过l1.val和l2.val比较大小，再借助ListNode temp将其插入至其中一个ListNode中，但在一开始调试过程中发现，若temp=q；（q=l2...]]></description><category></category></item><item><title><![CDATA[LeetCode(14)Longest Common Prefix]]></title><link>https://blog.youkuaiyun.com/qq_41007874/article/details/117254009</link><guid>https://blog.youkuaiyun.com/qq_41007874/article/details/117254009</guid><author>qq_41007874</author><pubDate>Tue, 25 May 2021 13:37:00 +0800</pubDate><description><![CDATA[题目：

Write a function to find the longest common prefix string amongst an array of strings.

If there is no common prefix, return an empty string"".

思路：

要求输出strs中最长重复的字符串，使用String类中的compareTo()方法比较字符串，使用substring（int beginIndex,int endIndex）截取字符串。该方法判断较.]]></description><category></category></item><item><title><![CDATA[LeetCode 2.Add Two Numbers]]></title><link>https://blog.youkuaiyun.com/qq_41007874/article/details/116986753</link><guid>https://blog.youkuaiyun.com/qq_41007874/article/details/116986753</guid><author>qq_41007874</author><pubDate>Tue, 18 May 2021 14:29:22 +0800</pubDate><description><![CDATA[题目：

You are given twonon-emptylinked lists representing two non-negative integers. The digits are stored inreverse order, and each of their nodes contains a single digit. Add the two numbers and return the sumas a linked list.

You may assume the two ...]]></description><category></category></item><item><title><![CDATA[LeetCode刷题（一）Two Sum]]></title><link>https://blog.youkuaiyun.com/qq_41007874/article/details/90199880</link><guid>https://blog.youkuaiyun.com/qq_41007874/article/details/90199880</guid><author>qq_41007874</author><pubDate>Tue, 14 May 2019 09:56:30 +0800</pubDate><description><![CDATA[题目：

Given an array of integers, return indices of the two numbers such that they add up to a specific target.

You may assume that each input would have exactly one solution, and you may not use the ...]]></description><category></category></item><item><title><![CDATA[Springboot（一）]]></title><link>https://blog.youkuaiyun.com/qq_41007874/article/details/89456932</link><guid>https://blog.youkuaiyun.com/qq_41007874/article/details/89456932</guid><author>qq_41007874</author><pubDate>Mon, 22 Apr 2019 18:16:05 +0800</pubDate><description><![CDATA[第一个Springboot创建

maven配置略

&lt;pom.xml&gt;代码如下


&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance...]]></description><category></category></item></channel></rss>