mirror of
https://github.com/youngyangyang04/leetcode-master.git
synced 2025-07-27 19:22:26 +08:00
499 lines
33 KiB
Markdown
499 lines
33 KiB
Markdown
目录：
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=================
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* [算法面试思维导图](#算法面试思维导图)
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* [算法文章精选](#算法文章精选)
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* [LeetCode 刷题攻略](#LeetCode-刷题攻略)
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* [算法模板](#算法模板)
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* [LeetCode 最强题解](#LeetCode-最强题解)
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* [关于作者](#关于作者)
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# 算法面试思维导图
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# 算法文章精选
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* [C++面试&C++学习指南知识点整理](https://github.com/youngyangyang04/TechCPP)
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* [程序员应该如何写简历（附简历模板）](https://mp.weixin.qq.com/s/PkBpde0PV65dJjj9zZJYtg)
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* [一线互联网公司技术面试的流程以及注意事项](https://mp.weixin.qq.com/s/1VMvQ_6HbVpEn85CNilTiw)
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* [究竟什么是时间复杂度，怎么求时间复杂度，看这一篇就够了](https://mp.weixin.qq.com/s/lYL9TSxLqCeFXIdjt4dcIw)
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* [一文带你彻底理解程序为什么会超时](https://mp.weixin.qq.com/s/T-vcJSkq2-0s0bBB-itWbQ)
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* [一场面试，带你彻底掌握递归算法的时间复杂度](https://mp.weixin.qq.com/s/Kt-Mvs8LeVqidLGUqySj1g)
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* [算法分析中的空间复杂度，你真的会了么？](https://mp.weixin.qq.com/s/sXjjnOUEQ4Gf5F9QCRzy7g)
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* [二分法其实很简单，为什么老是写不对！！](https://mp.weixin.qq.com/s/ICdahBRWbbEeEWHKjC8Alw)
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* [程序员算法面试中，必须掌握的数组理论知识](https://mp.weixin.qq.com/s/X7R55wSENyY62le0Fiawsg)
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* [这五道数组相关的面试题，你一定要会！](https://mp.weixin.qq.com/s/vdKHt2vFSZEouZASjdWieg)
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* [这六道哈希表相关的面试题，你一定要会！](https://mp.weixin.qq.com/s/nxuWv5cUhCPSbAdIHtWgSg)
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* [刷leetcode的时候，究竟什么时候可以使用库函数，什么时候不要使用库函数，过来人来说一说](https://leetcode-cn.com/circle/article/E1Kjzn/)
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* [关于链表，你该了解这些！](https://mp.weixin.qq.com/s/ntlZbEdKgnFQKZkSUAOSpQ)
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* [链表：听说用虚拟头节点会方便很多？](https://mp.weixin.qq.com/s/slM1CH5Ew9XzK93YOQYSjA)
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* [链表：一道题目考察了常见的五个操作！](https://mp.weixin.qq.com/s/Cf95Lc6brKL4g2j8YyF3Mg)
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* [链表：听说过两天反转链表又写不出来了？](https://mp.weixin.qq.com/s/pnvVP-0ZM7epB8y3w_Njwg)
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* [链表：环找到了，那入口呢？](https://mp.weixin.qq.com/s/_QVP3IkRZWx9zIpQRgajzA)
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* [关于哈希表，你该了解这些！](https://mp.weixin.qq.com/s/g8N6WmoQmsCUw3_BaWxHZA)
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* [哈希表：可以拿数组当哈希表来用，但哈希值不要太大](https://mp.weixin.qq.com/s/vM6OszkM6L1Mx2Ralm9Dig)
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* [哈希表：哈希值太大了，还是得用set](https://mp.weixin.qq.com/s/N9iqAchXreSVW7zXUS4BVA)
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* [哈希表：今天你快乐了么？](https://mp.weixin.qq.com/s/G4Q2Zfpfe706gLK7HpZHpA)
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* [哈希表：map等候多时了](https://mp.weixin.qq.com/s/uVAtjOHSeqymV8FeQbliJQ)
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* [哈希表：其实需要哈希的地方都能找到map的身影](https://mp.weixin.qq.com/s/Ue8pKKU5hw_m-jPgwlHcbA)
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* [哈希表：这道题目我做过？](https://mp.weixin.qq.com/s/sYZIR4dFBrw_lr3eJJnteQ)
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* [哈希表：解决了两数之和，那么能解决三数之和么？](https://mp.weixin.qq.com/s/r5cgZFu0tv4grBAexdcd8A)
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* [双指针法：一样的道理，能解决四数之和](https://mp.weixin.qq.com/s/nQrcco8AZJV1pAOVjeIU_g)
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* [必须掌握的数组理论知识](https://mp.weixin.qq.com/s/X7R55wSENyY62le0Fiawsg)
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* [数组：每次遇到二分法，都是一看就会，一写就废](https://mp.weixin.qq.com/s/fCf5QbPDtE6SSlZ1yh_q8Q)
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* [数组：就移除个元素很难么？](https://mp.weixin.qq.com/s/wj0T-Xs88_FHJFwayElQlA)
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* [数组：滑动窗口拯救了你](https://mp.weixin.qq.com/s/UrZynlqi4QpyLlLhBPglyg)
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* [数组：这个循环可以转懵很多人！](https://mp.weixin.qq.com/s/KTPhaeqxbMK9CxHUUgFDmg)
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* [数组：总结篇](https://mp.weixin.qq.com/s/LIfQFRJBH5ENTZpvixHEmg)
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* [字符串：这道题目，使用库函数一行代码搞定](https://mp.weixin.qq.com/s/X02S61WCYiCEhaik6VUpFA)
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* [字符串：简单的反转还不够！](https://mp.weixin.qq.com/s/XGSk1GyPWhfqj2g7Cb1Vgw)
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* [字符串：替换空格](https://mp.weixin.qq.com/s/t0A9C44zgM-RysAQV3GZpg)
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* [字符串：花式反转还不够！](https://mp.weixin.qq.com/s/X3qpi2v5RSp08mO-W5Vicw)
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* [字符串：反转个字符串还有这个用处？](https://mp.weixin.qq.com/s/PmcdiWSmmccHAONzU0ScgQ)
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* [字符串：KMP是时候上场了（一文读懂系列）](https://mp.weixin.qq.com/s/70OXnZ4Ez29CKRrUpVJmug)
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* [字符串：都来看看KMP的看家本领！](https://mp.weixin.qq.com/s/Gk9FKZ9_FSWLEkdGrkecyg)
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* [字符串：听说你对KMP有这些疑问？](https://mp.weixin.qq.com/s/mqx6IM2AO4kLZwvXdPtEeQ)
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* [字符串：KMP算法还能干这个！](https://mp.weixin.qq.com/s/lR2JPtsQSR2I_9yHbBmBuQ)
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* [字符串：前缀表不右移，难道就写不出KMP了？](https://mp.weixin.qq.com/s/p3hXynQM2RRROK5c6X7xfw)
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* [字符串：总结篇！](https://mp.weixin.qq.com/s/gtycjyDtblmytvBRFlCZJg)
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* [栈与队列：来看看栈和队列不为人知的一面](https://mp.weixin.qq.com/s/VZRjOccyE09aE-MgLbCMjQ)
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* [栈与队列：我用栈来实现队列怎么样？](https://mp.weixin.qq.com/s/P6tupDwRFi6Ay-L7DT4NVg)
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（持续更新中....）
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# LeetCode 刷题攻略
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刷题顺序：建议先从同一类型里题目开始刷起，同一类型里再从简单到中等到困难刷起，题型顺序建议：**数组-> 链表-> 哈希表->字符串->栈与队列->树**。
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这里我总结了各个类型的经典题目，**初学者可以按照如下顺序来刷题**，算法老手可以按照这个list查缺补漏！
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* 数组经典题目
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* [0035.搜索插入位置](https://mp.weixin.qq.com/s/fCf5QbPDtE6SSlZ1yh_q8Q)
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* [0027.移除元素](https://mp.weixin.qq.com/s/wj0T-Xs88_FHJFwayElQlA)
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* [0026.删除排序数组中的重复项](https://github.com/youngyangyang04/leetcode/blob/master/problems/0026.删除排序数组中的重复项.md)
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* [0209.长度最小的子数组](https://mp.weixin.qq.com/s/UrZynlqi4QpyLlLhBPglyg)
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* [0059.螺旋矩阵II](https://mp.weixin.qq.com/s/KTPhaeqxbMK9CxHUUgFDmg)
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* 链表经典题目
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* [0203.移除链表元素](https://mp.weixin.qq.com/s/slM1CH5Ew9XzK93YOQYSjA)
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* [0707.设计链表](https://mp.weixin.qq.com/s/Cf95Lc6brKL4g2j8YyF3Mg)
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* [0206.翻转链表](https://mp.weixin.qq.com/s/pnvVP-0ZM7epB8y3w_Njwg)
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* [面试题02.07.链表相交](https://github.com/youngyangyang04/leetcode/blob/master/problems/面试题02.07.链表相交.md)
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* [0142.环形链表II](https://mp.weixin.qq.com/s/_QVP3IkRZWx9zIpQRgajzA)
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* 哈希表经典题目
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* [0242.有效的字母异位词](https://mp.weixin.qq.com/s/vM6OszkM6L1Mx2Ralm9Dig)
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* [0383.赎金信](https://mp.weixin.qq.com/s/sYZIR4dFBrw_lr3eJJnteQ)
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* [0575.分糖果](https://github.com/youngyangyang04/leetcode/blob/master/problems/0575.分糖果.md)
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* [0349.两个数组的交集](https://mp.weixin.qq.com/s/N9iqAchXreSVW7zXUS4BVA)
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* [0202.快乐数](https://mp.weixin.qq.com/s/G4Q2Zfpfe706gLK7HpZHpA)
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* [0001.两数之和](https://mp.weixin.qq.com/s/uVAtjOHSeqymV8FeQbliJQ)
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* [0454.四数相加II](https://mp.weixin.qq.com/s/Ue8pKKU5hw_m-jPgwlHcbA)
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* [0015.三数之和](https://mp.weixin.qq.com/s/r5cgZFu0tv4grBAexdcd8A)
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* [0018.四数之和](https://mp.weixin.qq.com/s/nQrcco8AZJV1pAOVjeIU_g)
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* [0219.存在重复元素II](https://github.com/youngyangyang04/leetcode/blob/master/problems/0219.存在重复元素II.md)
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* 0220.存在重复元素III
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* 循环不变量原则
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* [0035.搜索插入位置](https://mp.weixin.qq.com/s/fCf5QbPDtE6SSlZ1yh_q8Q)
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* [0059.螺旋矩阵II](https://mp.weixin.qq.com/s/KTPhaeqxbMK9CxHUUgFDmg)
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* 字符串经典题目
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* [0344.反转字符串](https://mp.weixin.qq.com/s/X02S61WCYiCEhaik6VUpFA)
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* [0541.反转字符串II](https://mp.weixin.qq.com/s/XGSk1GyPWhfqj2g7Cb1Vgw)
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* [剑指Offer05.替换空格](https://mp.weixin.qq.com/s/t0A9C44zgM-RysAQV3GZpg)
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* [0151.翻转字符串里的单词](https://mp.weixin.qq.com/s/X3qpi2v5RSp08mO-W5Vicw)
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* [剑指Offer58-II.左旋转字符串](https://mp.weixin.qq.com/s/PmcdiWSmmccHAONzU0ScgQ)
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* [0028.实现strStr()](https://mp.weixin.qq.com/s/Gk9FKZ9_FSWLEkdGrkecyg)
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* [0459.重复的子字符串](https://mp.weixin.qq.com/s/lR2JPtsQSR2I_9yHbBmBuQ)
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* 双指针法经典题目
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* [0027.移除元素](https://mp.weixin.qq.com/s/wj0T-Xs88_FHJFwayElQlA)
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* [0015.三数之和](https://mp.weixin.qq.com/s/r5cgZFu0tv4grBAexdcd8A)
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* [0018.四数之和](https://mp.weixin.qq.com/s/nQrcco8AZJV1pAOVjeIU_g)
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* [0026.删除排序数组中的重复项](https://github.com/youngyangyang04/leetcode/blob/master/problems/0026.删除排序数组中的重复项.md)
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* [0206.翻转链表](https://mp.weixin.qq.com/s/pnvVP-0ZM7epB8y3w_Njwg)
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* [0142.环形链表II](https://mp.weixin.qq.com/s/_QVP3IkRZWx9zIpQRgajzA)
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* [0344.反转字符串](https://mp.weixin.qq.com/s/X02S61WCYiCEhaik6VUpFA)
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* [剑指Offer05.替换空格](https://mp.weixin.qq.com/s/t0A9C44zgM-RysAQV3GZpg)
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* 栈与队列经典题目
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* [0232.用栈实现队列](https://github.com/youngyangyang04/leetcode/blob/master/problems/0232.用栈实现队列.md)
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* [0225.用队列实现栈](https://github.com/youngyangyang04/leetcode/blob/master/problems/0225.用队列实现栈.md)
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* [0020.有效的括号](https://github.com/youngyangyang04/leetcode/blob/master/problems/0020.有效的括号.md)
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* [1047.删除字符串中的所有相邻重复项](https://github.com/youngyangyang04/leetcode/blob/master/problems/1047.删除字符串中的所有相邻重复项.md)
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* [0239.滑动窗口最大值](https://github.com/youngyangyang04/leetcode/blob/master/problems/0239.滑动窗口最大值.md)
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* [0347.前K个高频元素](https://github.com/youngyangyang04/leetcode/blob/master/problems/0347.前K个高频元素.md)
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* 二叉树经典题目
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* [0144.二叉树的前序遍历](https://github.com/youngyangyang04/leetcode/blob/master/problems/0144.二叉树的前序遍历.md)
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* [0094.二叉树的中序遍历](https://github.com/youngyangyang04/leetcode/blob/master/problems/0094.二叉树的中序遍历.md)
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* [0145.二叉树的后序遍历](https://github.com/youngyangyang04/leetcode/blob/master/problems/0145.二叉树的后序遍历.md)
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* [0102.二叉树的层序遍历](https://github.com/youngyangyang04/leetcode/blob/master/problems/0102.二叉树的层序遍历.md)
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* [0199.二叉树的右视图](https://github.com/youngyangyang04/leetcode/blob/master/problems/0199.二叉树的右视图.md)
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* [0226.翻转二叉树](https://github.com/youngyangyang04/leetcode/blob/master/problems/0226.翻转二叉树.md)
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* [0101.对称二叉树](https://github.com/youngyangyang04/leetcode/blob/master/problems/0101.对称二叉树.md)
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* [0104.二叉树的最大深度](https://github.com/youngyangyang04/leetcode/blob/master/problems/0104.二叉树的最大深度.md)
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* [0111.二叉树的最小深度](https://github.com/youngyangyang04/leetcode/blob/master/problems/0111.二叉树的最小深度.md)
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* [0222.完全二叉树的节点个数](https://github.com/youngyangyang04/leetcode/blob/master/problems/0222.完全二叉树的节点个数.md)
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* [0654.最大二叉树](https://github.com/youngyangyang04/leetcode/blob/master/problems/0654.最大二叉树.md)
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* [0617.合并二叉树](https://github.com/youngyangyang04/leetcode/blob/master/problems/0617.合并二叉树.md)
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* [0700.二叉搜索树中的搜索](https://github.com/youngyangyang04/leetcode/blob/master/problems/0700.二叉搜索树中的搜索.md)
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* [0098.验证二叉搜索树](https://github.com/youngyangyang04/leetcode/blob/master/problems/0098.验证二叉搜索树.md)
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* [0701.二叉搜索树中的插入操作](https://github.com/youngyangyang04/leetcode/blob/master/problems/0701.二叉搜索树中的插入操作.md)
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* [0450.删除二叉搜索树中的节点](https://github.com/youngyangyang04/leetcode/blob/master/problems/0450.删除二叉搜索树中的节点.md)
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（持续补充ing）
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# 算法模板
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## 二分查找法
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```
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class Solution {
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public:
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int searchInsert(vector<int>& nums, int target) {
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int n = nums.size();
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int left = 0;
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int right = n; // 我们定义target在左闭右开的区间里，[left, right)
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while (left < right) { // 因为left == right的时候，在[left, right)是无效的空间
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int middle = left + ((right - left) >> 1);
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if (nums[middle] > target) {
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right = middle; // target 在左区间，因为是左闭右开的区间，nums[middle]一定不是我们的目标值，所以right = middle，在[left, middle)中继续寻找目标值
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} else if (nums[middle] < target) {
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left = middle + 1; // target 在右区间，在 [middle+1, right)中
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} else { // nums[middle] == target
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return middle; // 数组中找到目标值的情况，直接返回下标
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}
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}
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return right;
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}
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};
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```
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## KMP
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```
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void kmp(int* next, const string& s){
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next[0] = -1;
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int j = -1;
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for(int i = 1; i < s.size(); i++){
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while (j >= 0 && s[i] != s[j + 1]) {
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j = next[j];
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}
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if (s[i] == s[j + 1]) {
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j++;
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}
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next[i] = j;
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}
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}
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```
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## 二叉树
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二叉树的定义：
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```
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struct TreeNode {
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int val;
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TreeNode *left;
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TreeNode *right;
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TreeNode(int x) : val(x), left(NULL), right(NULL) {}
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};
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```
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### 深度优先遍历（递归）
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前序遍历（中左右）
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```
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||
void traversal(TreeNode* cur, vector<int>& vec) {
|
||
if (cur == NULL) return;
|
||
vec.push_back(cur->val); // 中 ，同时也是处理节点逻辑的地方
|
||
traversal(cur->left, vec); // 左
|
||
traversal(cur->right, vec); // 右
|
||
}
|
||
```
|
||
中序遍历（左中右）
|
||
```
|
||
void traversal(TreeNode* cur, vector<int>& vec) {
|
||
if (cur == NULL) return;
|
||
traversal(cur->left, vec); // 左
|
||
vec.push_back(cur->val); // 中 ，同时也是处理节点逻辑的地方
|
||
traversal(cur->right, vec); // 右
|
||
}
|
||
```
|
||
中序遍历（中左右）
|
||
```
|
||
void traversal(TreeNode* cur, vector<int>& vec) {
|
||
if (cur == NULL) return;
|
||
vec.push_back(cur->val); // 中 ，同时也是处理节点逻辑的地方
|
||
traversal(cur->left, vec); // 左
|
||
traversal(cur->right, vec); // 右
|
||
}
|
||
```
|
||
|
||
### 深度优先遍历（迭代法）
|
||
|
||
相关题解：[0094.二叉树的中序遍历](https://github.com/youngyangyang04/leetcode/blob/master/problems/0094.二叉树的中序遍历.md)
|
||
|
||
前序遍历（中左右）
|
||
```
|
||
vector<int> preorderTraversal(TreeNode* root) {
|
||
vector<int> result;
|
||
stack<TreeNode*> st;
|
||
if (root != NULL) st.push(root);
|
||
while (!st.empty()) {
|
||
TreeNode* node = st.top();
|
||
if (node != NULL) {
|
||
st.pop();
|
||
if (node->right) st.push(node->right); // 右
|
||
if (node->left) st.push(node->left); // 左
|
||
st.push(node); // 中
|
||
st.push(NULL);
|
||
} else {
|
||
st.pop();
|
||
node = st.top();
|
||
st.pop();
|
||
result.push_back(node->val); // 节点处理逻辑
|
||
}
|
||
}
|
||
return result;
|
||
}
|
||
|
||
```
|
||
|
||
中序遍历（左中右）
|
||
```
|
||
vector<int> inorderTraversal(TreeNode* root) {
|
||
vector<int> result; // 存放中序遍历的元素
|
||
stack<TreeNode*> st;
|
||
if (root != NULL) st.push(root);
|
||
while (!st.empty()) {
|
||
TreeNode* node = st.top();
|
||
if (node != NULL) {
|
||
st.pop();
|
||
if (node->right) st.push(node->right); // 右
|
||
st.push(node); // 中
|
||
st.push(NULL);
|
||
if (node->left) st.push(node->left); // 左
|
||
} else {
|
||
st.pop();
|
||
node = st.top();
|
||
st.pop();
|
||
result.push_back(node->val); // 节点处理逻辑
|
||
}
|
||
}
|
||
return result;
|
||
}
|
||
```
|
||
|
||
后序遍历（左右中）
|
||
```
|
||
vector<int> postorderTraversal(TreeNode* root) {
|
||
vector<int> result;
|
||
stack<TreeNode*> st;
|
||
if (root != NULL) st.push(root);
|
||
while (!st.empty()) {
|
||
TreeNode* node = st.top();
|
||
if (node != NULL) {
|
||
st.pop();
|
||
st.push(node); // 中
|
||
st.push(NULL);
|
||
if (node->right) st.push(node->right); // 右
|
||
if (node->left) st.push(node->left); // 左
|
||
|
||
} else {
|
||
st.pop();
|
||
node = st.top();
|
||
st.pop();
|
||
result.push_back(node->val); // 节点处理逻辑
|
||
}
|
||
}
|
||
return result;
|
||
}
|
||
```
|
||
### 广度优先遍历（队列）
|
||
|
||
相关题解：[0102.二叉树的层序遍历](https://github.com/youngyangyang04/leetcode/blob/master/problems/0102.二叉树的层序遍历.md)
|
||
|
||
```
|
||
vector<vector<int>> levelOrder(TreeNode* root) {
|
||
queue<TreeNode*> que;
|
||
if (root != NULL) que.push(root);
|
||
vector<vector<int>> result;
|
||
while (!que.empty()) {
|
||
int size = que.size();
|
||
vector<int> vec;
|
||
for (int i = 0; i < size; i++) {// 这里一定要使用固定大小size，不要使用que.size()
|
||
TreeNode* node = que.front();
|
||
que.pop();
|
||
vec.push_back(node->val); // 节点处理的逻辑
|
||
if (node->left) que.push(node->left);
|
||
if (node->right) que.push(node->right);
|
||
}
|
||
result.push_back(vec);
|
||
}
|
||
return result;
|
||
}
|
||
|
||
```
|
||
|
||
|
||
|
||
可以直接解决如下题目：
|
||
|
||
* [0102.二叉树的层序遍历](https://github.com/youngyangyang04/leetcode/blob/master/problems/0102.二叉树的层序遍历.md)
|
||
* [0199.二叉树的右视图](https://github.com/youngyangyang04/leetcode/blob/master/problems/0199.二叉树的右视图.md)
|
||
* [0104.二叉树的最大深度 （迭代法）](https://github.com/youngyangyang04/leetcode/blob/master/problems/0104.二叉树的最大深度.md)
|
||
|
||
* [0111.二叉树的最小深度（迭代法）]((https://github.com/youngyangyang04/leetcode/blob/master/problems/0111.二叉树的最小深度.md))
|
||
* [0222.完全二叉树的节点个数（迭代法）](https://github.com/youngyangyang04/leetcode/blob/master/problems/0222.完全二叉树的节点个数.md)
|
||
|
||
### 二叉树深度
|
||
|
||
```
|
||
int getDepth(TreeNode* node) {
|
||
if (node == NULL) return 0;
|
||
return 1 + max(getDepth(node->left), getDepth(node->right));
|
||
}
|
||
```
|
||
|
||
### 二叉树节点数量
|
||
|
||
```
|
||
int countNodes(TreeNode* root) {
|
||
if (root == NULL) return 0;
|
||
return 1 + countNodes(root->left) + countNodes(root->right);
|
||
}
|
||
```
|
||
|
||
## 回溯算法
|
||
|
||
```
|
||
backtracking() {
|
||
if (终止条件) {
|
||
存放结果;
|
||
}
|
||
|
||
for (选择：选择列表（可以想成树中节点孩子的数量）) {
|
||
递归，处理节点;
|
||
backtracking();
|
||
回溯，撤销处理结果
|
||
}
|
||
}
|
||
|
||
```
|
||
|
||
（持续补充ing）
|
||
|
||
# LeetCode 最强题解:
|
||
|
||
|题目 | 类型 | 难度 | 解题方法 |
|
||
|---|---| ---| --- |
|
||
|[0001.两数之和](https://github.com/youngyangyang04/leetcode/blob/master/problems/0001.两数之和.md) | 数组|简单|**暴力** **哈希**|
|
||
|[0015.三数之和](https://github.com/youngyangyang04/leetcode/blob/master/problems/0015.三数之和.md) | 数组 |中等|**双指针** **哈希**|
|
||
|[0017.电话号码的字母组合](https://github.com/youngyangyang04/leetcode/blob/master/problems/0017.电话号码的字母组合.md) | 回溯 |中等|**回溯**|
|
||
|[0018.四数之和](https://github.com/youngyangyang04/leetcode/blob/master/problems/0018.四数之和.md) | 数组 |中等|**双指针**|
|
||
|[0020.有效的括号](https://github.com/youngyangyang04/leetcode/blob/master/problems/0020.有效的括号.md) | 栈 |简单|**栈**|
|
||
|[0021.合并两个有序链表](https://github.com/youngyangyang04/leetcode/blob/master/problems/0021.合并两个有序链表.md) |链表 |简单|**模拟** |
|
||
|[0026.删除排序数组中的重复项](https://github.com/youngyangyang04/leetcode/blob/master/problems/0026.删除排序数组中的重复项.md) |数组 |简单|**暴力** **快慢指针/快慢指针** |
|
||
|[0027.移除元素](https://github.com/youngyangyang04/leetcode/blob/master/problems/0027.移除元素.md) |数组 |简单| **暴力** **双指针/快慢指针/双指针**|
|
||
|[0028.实现strStr()](https://github.com/youngyangyang04/leetcode/blob/master/problems/0028.实现strStr().md) |字符串 |简单| **KMP** |
|
||
|[0035.搜索插入位置](https://github.com/youngyangyang04/leetcode/blob/master/problems/0035.搜索插入位置.md) |数组 |简单| **暴力** **二分**|
|
||
|[0037.解数独](https://github.com/youngyangyang04/leetcode/blob/master/problems/0037.解数独.md) |回溯 |困难| **回溯**|
|
||
|[0039.组合总和](https://github.com/youngyangyang04/leetcode/blob/master/problems/0039.组合总和.md) |数组/回溯 |中等| **回溯**|
|
||
|[0040.组合总和II](https://github.com/youngyangyang04/leetcode/blob/master/problems/0040.组合总和II.md) |数组/回溯 |中等| **回溯**|
|
||
|[0046.全排列](https://github.com/youngyangyang04/leetcode/blob/master/problems/0046.全排列.md) |回溯|中等| **回溯**|
|
||
|[0047.全排列II](https://github.com/youngyangyang04/leetcode/blob/master/problems/0047.全排列II.md) |回溯|中等| **回溯**|
|
||
|[0051.N皇后](https://github.com/youngyangyang04/leetcode/blob/master/problems/0051.N皇后.md) |回溯|困难| **回溯**|
|
||
|[0052.N皇后II](https://github.com/youngyangyang04/leetcode/blob/master/problems/0052.N皇后II.md) |回溯|困难| **回溯**|
|
||
|[0053.最大子序和](https://github.com/youngyangyang04/leetcode/blob/master/problems/0053.最大子序和.md) |数组 |简单|**暴力** **贪心** 动态规划 分治|
|
||
|[0059.螺旋矩阵II](https://github.com/youngyangyang04/leetcode/blob/master/problems/0059.螺旋矩阵II.md) |数组 |中等|**模拟**|
|
||
|[0077.组合](https://github.com/youngyangyang04/leetcode/blob/master/problems/0077.组合.md) |回溯 |中等|**回溯**|
|
||
|[0078.子集](https://github.com/youngyangyang04/leetcode/blob/master/problems/0078.子集.md) |回溯/数组 |中等|**回溯**|
|
||
|[0083.删除排序链表中的重复元素](https://github.com/youngyangyang04/leetcode/blob/master/problems/0083.删除排序链表中的重复元素.md) |链表 |简单|**模拟**|
|
||
|[0090.子集II](https://github.com/youngyangyang04/leetcode/blob/master/problems/0090.子集II.md) |回溯/数组 |中等|**回溯**|
|
||
|[0093.复原IP地址](https://github.com/youngyangyang04/leetcode/blob/master/problems/0093.复原IP地址) |回溯 |中等|**回溯**|
|
||
|[0094.二叉树的中序遍历](https://github.com/youngyangyang04/leetcode/blob/master/problems/0094.二叉树的中序遍历.md) |树 |中等|**递归** **迭代/栈**|
|
||
|[0098.验证二叉搜索树](https://github.com/youngyangyang04/leetcode/blob/master/problems/0098.验证二叉搜索树.md) |树 |中等|**递归**|
|
||
|[0100.相同的树](https://github.com/youngyangyang04/leetcode/blob/master/problems/0100.相同的树.md) |树 |简单|**递归** |
|
||
|[0101.对称二叉树](https://github.com/youngyangyang04/leetcode/blob/master/problems/0101.对称二叉树.md) |树 |简单|**递归** **迭代/队列/栈**|
|
||
|[0102.二叉树的层序遍历](https://github.com/youngyangyang04/leetcode/blob/master/problems/0102.二叉树的层序遍历.md) |树 |中等|**广度优先搜索/队列**|
|
||
|[0104.二叉树的最大深度](https://github.com/youngyangyang04/leetcode/blob/master/problems/0104.二叉树的最大深度.md) |树 |简单|**递归** **迭代/队列/BFS**|
|
||
|[0107.二叉树的层次遍历II](https://github.com/youngyangyang04/leetcode/blob/master/problems/0107.二叉树的层次遍历II.md) |树 |简单|**广度优先搜索/队列/BFS**|
|
||
|[0110.平衡二叉树](https://github.com/youngyangyang04/leetcode/blob/master/problems/0110.平衡二叉树.md) |树 |简单|**递归**|
|
||
|[0111.二叉树的最小深度](https://github.com/youngyangyang04/leetcode/blob/master/problems/0111.二叉树的最小深度.md) |树 |简单|**递归** **队列/BFS**|
|
||
|[0131.分割回文串](https://github.com/youngyangyang04/leetcode/blob/master/problems/0131.分割回文串.md) |回溯 |中等|**回溯**|
|
||
|[0142.环形链表II](https://github.com/youngyangyang04/leetcode/blob/master/problems/0142.环形链表II.md) |链表 |中等|**快慢指针/双指针**|
|
||
|[0144.二叉树的前序遍历](https://github.com/youngyangyang04/leetcode/blob/master/problems/0144.二叉树的前序遍历.md) |树 |中等|**递归** **迭代/栈**|
|
||
|[0145.二叉树的后序遍历](https://github.com/youngyangyang04/leetcode/blob/master/problems/0145.二叉树的后序遍历.md) |树 |困难|**递归** **迭代/栈**|
|
||
|[0151.翻转字符串里的单词](https://github.com/youngyangyang04/leetcode/blob/master/problems/0151.翻转字符串里的单词.md) |字符串 |中等|**模拟/双指针**|
|
||
|[0155.最小栈](https://github.com/youngyangyang04/leetcode/blob/master/problems/0155.最小栈.md) |栈 |简单|**栈**|
|
||
|[0199.二叉树的右视图](https://github.com/youngyangyang04/leetcode/blob/master/problems/0199.二叉树的右视图.md) |二叉树 |中等|**广度优先遍历/队列**|
|
||
|[0202.快乐数](https://github.com/youngyangyang04/leetcode/blob/master/problems/0202.快乐数.md) |哈希表 |简单|**哈希**|
|
||
|[0203.移除链表元素](https://github.com/youngyangyang04/leetcode/blob/master/problems/0203.移除链表元素.md) |链表 |简单|**模拟** **虚拟头结点**|
|
||
|[0205.同构字符串](https://github.com/youngyangyang04/leetcode/blob/master/problems/0205.同构字符串.md) |哈希表 |简单| **哈希**|
|
||
|[0206.翻转链表](https://github.com/youngyangyang04/leetcode/blob/master/problems/0206.翻转链表.md) |链表 |简单| **双指针法** **递归**|
|
||
|[0209.长度最小的子数组](https://github.com/youngyangyang04/leetcode/blob/master/problems/0209.长度最小的子数组.md) |数组 |中等| **暴力** **滑动窗口**|
|
||
|[0216.组合总和III](https://github.com/youngyangyang04/leetcode/blob/master/problems/0216.组合总和III.md) |数组/回溯 |中等| **回溯算法**|
|
||
|[0219.存在重复元素II](https://github.com/youngyangyang04/leetcode/blob/master/problems/0219.存在重复元素II.md) | 哈希表 |简单| **哈希** |
|
||
|[0222.完全二叉树的节点个数](https://github.com/youngyangyang04/leetcode/blob/master/problems/0222.完全二叉树的节点个数.md) | 树 |简单| **递归** |
|
||
|[0225.用队列实现栈](https://github.com/youngyangyang04/leetcode/blob/master/problems/0225.用队列实现栈.md) | 队列 |简单| **队列** |
|
||
|[0226.翻转二叉树](https://github.com/youngyangyang04/leetcode/blob/master/problems/0226.翻转二叉树.md) |二叉树 |简单| **递归** **迭代**|
|
||
|[0232.用栈实现队列](https://github.com/youngyangyang04/leetcode/blob/master/problems/0232.用栈实现队列.md) | 栈 |简单| **栈** |
|
||
|[0237.删除链表中的节点](https://github.com/youngyangyang04/leetcode/blob/master/problems/0237.删除链表中的节点.md) |链表 |简单| **原链表移除** **添加虚拟节点** 递归|
|
||
|[0239.滑动窗口最大值](https://github.com/youngyangyang04/leetcode/blob/master/problems/0239.滑动窗口最大值.md) |滑动窗口/队列 |困难| **单调队列**|
|
||
|[0242.有效的字母异位词](https://github.com/youngyangyang04/leetcode/blob/master/problems/0242.有效的字母异位词.md) |哈希表 |简单| **哈希**|
|
||
|[0257.二叉树的所有路径](https://github.com/youngyangyang04/leetcode/blob/master/problems/0257.二叉树的所有路径.md) |树 |简单| **递归/回溯**|
|
||
|[0332.重新安排行程](https://github.com/youngyangyang04/leetcode/blob/master/problems/0332.重新安排行程.md) |深度优先搜索/回溯 |中等| **深度优先搜索/回溯算法**|
|
||
|[0344.反转字符串](https://github.com/youngyangyang04/leetcode/blob/master/problems/0344.反转字符串.md) |字符串 |简单| **双指针**|
|
||
|[0347.前K个高频元素](https://github.com/youngyangyang04/leetcode/blob/master/problems/0347.前K个高频元素.md) |哈希/堆/优先级队列 |中等| **哈希/优先级队列**|
|
||
|[0349.两个数组的交集](https://github.com/youngyangyang04/leetcode/blob/master/problems/0349.两个数组的交集.md) |哈希表 |简单|**哈希**|
|
||
|[0350.两个数组的交集II](https://github.com/youngyangyang04/leetcode/blob/master/problems/0350.两个数组的交集II.md) |哈希表 |简单|**哈希**|
|
||
|[0383.赎金信](https://github.com/youngyangyang04/leetcode/blob/master/problems/0383.赎金信.md) |数组 |简单|**暴力** **字典计数** **哈希**|
|
||
|[0434.字符串中的单词数](https://github.com/youngyangyang04/leetcode/blob/master/problems/0434.字符串中的单词数.md) |字符串 |简单|**模拟**|
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|[0450.删除二叉搜索树中的节点](https://github.com/youngyangyang04/leetcode/blob/master/problems/0450.删除二叉搜索树中的节点.md) |树 |中等|**递归**|
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|[0454.四数相加II](https://github.com/youngyangyang04/leetcode/blob/master/problems/0454.四数相加II.md) |哈希表 |中等| **哈希**|
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|[0459.重复的子字符串](https://github.com/youngyangyang04/leetcode/blob/master/problems/0459.重复的子字符串.md) |字符创 |简单| **KMP**|
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|[0486.预测赢家](https://github.com/youngyangyang04/leetcode/blob/master/problems/0486.预测赢家.md) |动态规划 |中等| **递归** **记忆递归** **动态规划**|
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|[0491.递增子序列](https://github.com/youngyangyang04/leetcode/blob/master/problems/0491.递增子序列.md) |深度优先搜索 |中等|**深度优先搜索/回溯算法**|
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|[0541.反转字符串II](https://github.com/youngyangyang04/leetcode/blob/master/problems/0541.反转字符串II.md) |字符串 |简单| **模拟**|
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|[0575.分糖果](https://github.com/youngyangyang04/leetcode/blob/master/problems/0575.分糖果.md) |哈希表 |简单|**哈希**|
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|[0617.合并二叉树](https://github.com/youngyangyang04/leetcode/blob/master/problems/0617.合并二叉树.md) |树 |简单|**递归** **迭代**|
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|[0654.最大二叉树](https://github.com/youngyangyang04/leetcode/blob/master/problems/0654.最大二叉树.md) |树 |中等|**递归**|
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|[0700.二叉搜索树中的搜索](https://github.com/youngyangyang04/leetcode/blob/master/problems/0700.二叉搜索树中的搜索.md) |树 |简单|**递归** **迭代**|
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|[0701.二叉搜索树中的插入操作](https://github.com/youngyangyang04/leetcode/blob/master/problems/0701.二叉搜索树中的插入操作.md) |树 |简单|**递归** **迭代**|
|
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|[0705.设计哈希集合](https://github.com/youngyangyang04/leetcode/blob/master/problems/0705.设计哈希集合.md) |哈希表 |简单|**模拟**|
|
||
|[0707.设计链表](https://github.com/youngyangyang04/leetcode/blob/master/problems/0707.设计链表.md) |链表 |中等|**模拟**|
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||
|[0841.钥匙和房间](https://github.com/youngyangyang04/leetcode/blob/master/problems/0841.钥匙和房间.md) |孤岛问题 |中等|**bfs** **dfs**|
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|[1047.删除字符串中的所有相邻重复项](https://github.com/youngyangyang04/leetcode/blob/master/problems/1047.删除字符串中的所有相邻重复项.md) |栈 |简单|**栈**|
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||
|[剑指Offer05.替换空格](https://github.com/youngyangyang04/leetcode/blob/master/problems/剑指Offer05.替换空格.md) |字符串 |简单|**双指针**|
|
||
|[ 剑指Offer58-I.翻转单词顺序](https://github.com/youngyangyang04/leetcode/blob/master/problems/剑指Offer05.替换空格.md) |字符串 |简单|**模拟/双指针**|
|
||
|[剑指Offer58-II.左旋转字符串](https://github.com/youngyangyang04/leetcode/blob/master/problems/剑指Offer58-II.左旋转字符串.md) |字符串 |简单|**反转操作**|
|
||
|[面试题02.07.链表相交](https://github.com/youngyangyang04/leetcode/blob/master/problems/面试题02.07.链表相交.md) |链表 |简单|**模拟**|
|
||
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持续更新中....
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# 关于作者
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大家好，我是程序员Carl，ACM 校赛、黑龙江省赛、东北四省赛金牌，和亚洲区域赛铜牌获得者，哈工大计算机硕士毕业，先后在腾讯和百度从事后端技术研发，CSDN博客专家。对算法和C++后端技术有一定的见解，利用工作之余重新刷leetcode。
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