---
comments: true
edit_url: https://github.com/doocs/leetcode/edit/main/lcof/README.md
---

# 《剑指 Offer（第 2 版）》系列

![](./lcof.png)

本书精选谷歌、微软等知名 IT 企业的典型面试题，系统地总结了如何在面试时写出高质量代码，如何优化代码效率，以及分析、解决难题的常用方法。

[English Version](/lcof/README_EN.md)

## 题解

列表所有题解均由 [开源社区 Doocs](https://github.com/doocs) 贡献者提供，正在完善中，欢迎贡献你的题解！

快速搜索题号、题解、标签等，请善用 <kbd>Control</kbd> + <kbd>F</kbd>（或者 <kbd>Command</kbd> + <kbd>F</kbd>）。

| 题号                                                                                                 | 题解                                                                                                                                                                                                                       | 标签                  | 难度 |
| ---------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | --------------------- | ---- |
| [03](https://leetcode.cn/problems/shu-zu-zhong-zhong-fu-de-shu-zi-lcof)                              | [数组中重复的数字](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9803.%20%E6%95%B0%E7%BB%84%E4%B8%AD%E9%87%8D%E5%A4%8D%E7%9A%84%E6%95%B0%E5%AD%97/README.md)                                                                              | `数组`,`哈希表`       | 简单 |
| [04](https://leetcode.cn/problems/er-wei-shu-zu-zhong-de-cha-zhao-lcof)                              | [二维数组中的查找](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9804.%20%E4%BA%8C%E7%BB%B4%E6%95%B0%E7%BB%84%E4%B8%AD%E7%9A%84%E6%9F%A5%E6%89%BE/README.md)                                                                              | `数组`,`双指针`       | 中等 |
| [05](https://leetcode.cn/problems/ti-huan-kong-ge-lcof)                                              | [替换空格](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9805.%20%E6%9B%BF%E6%8D%A2%E7%A9%BA%E6%A0%BC/README.md)                                                                                                                          |                       | 简单 |
| [06](https://leetcode.cn/problems/cong-wei-dao-tou-da-yin-lian-biao-lcof)                            | [从尾到头打印链表](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9806.%20%E4%BB%8E%E5%B0%BE%E5%88%B0%E5%A4%B4%E6%89%93%E5%8D%B0%E9%93%BE%E8%A1%A8/README.md)                                                                              |                       | 简单 |
| [07](https://leetcode.cn/problems/zhong-jian-er-cha-shu-lcof)                                        | [重建二叉树](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9807.%20%E9%87%8D%E5%BB%BA%E4%BA%8C%E5%8F%89%E6%A0%91/README.md)                                                                                                               | `树`,`递归`           | 中等 |
| [09](https://leetcode.cn/problems/yong-liang-ge-zhan-shi-xian-dui-lie-lcof)                          | [用两个栈实现队列](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9809.%20%E7%94%A8%E4%B8%A4%E4%B8%AA%E6%A0%88%E5%AE%9E%E7%8E%B0%E9%98%9F%E5%88%97/README.md)                                                                              | `栈`,`设计`           | 简单 |
| [10- I](https://leetcode.cn/problems/fei-bo-na-qi-shu-lie-lcof)                                      | [斐波那契数列](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9810-%20I.%20%E6%96%90%E6%B3%A2%E9%82%A3%E5%A5%91%E6%95%B0%E5%88%97/README.md)                                                                                               | `递归`                | 简单 |
| [10- II](https://leetcode.cn/problems/qing-wa-tiao-tai-jie-wen-ti-lcof)                              | [青蛙跳台阶问题](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9810-%20II.%20%E9%9D%92%E8%9B%99%E8%B7%B3%E5%8F%B0%E9%98%B6%E9%97%AE%E9%A2%98/README.md)                                                                                   | `递归`                | 简单 |
| [11](https://leetcode.cn/problems/xuan-zhuan-shu-zu-de-zui-xiao-shu-zi-lcof)                         | [旋转数组的最小数字](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9811.%20%E6%97%8B%E8%BD%AC%E6%95%B0%E7%BB%84%E7%9A%84%E6%9C%80%E5%B0%8F%E6%95%B0%E5%AD%97/README.md)                                                                   | `二分查找`            | 简单 |
| [12](https://leetcode.cn/problems/ju-zhen-zhong-de-lu-jing-lcof)                                     | [矩阵中的路径](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9812.%20%E7%9F%A9%E9%98%B5%E4%B8%AD%E7%9A%84%E8%B7%AF%E5%BE%84/README.md)                                                                                                    | `动态规划`            | 中等 |
| [13](https://leetcode.cn/problems/ji-qi-ren-de-yun-dong-fan-wei-lcof)                                | [机器人的运动范围](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9813.%20%E6%9C%BA%E5%99%A8%E4%BA%BA%E7%9A%84%E8%BF%90%E5%8A%A8%E8%8C%83%E5%9B%B4/README.md)                                                                              |                       | 中等 |
| [14- I](https://leetcode.cn/problems/jian-sheng-zi-lcof)                                             | [剪绳子](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9814-%20I.%20%E5%89%AA%E7%BB%B3%E5%AD%90/README.md)                                                                                                                                | `数学`,`动态规划`     | 中等 |
| [14- II](https://leetcode.cn/problems/jian-sheng-zi-ii-lcof)                                         | [剪绳子 II](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9814-%20II.%20%E5%89%AA%E7%BB%B3%E5%AD%90%20II/README.md)                                                                                                                       | `数学`,`动态规划`     | 中等 |
| [15](https://leetcode.cn/problems/er-jin-zhi-zhong-1de-ge-shu-lcof)                                  | [二进制中 1 的个数](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9815.%20%E4%BA%8C%E8%BF%9B%E5%88%B6%E4%B8%AD1%E7%9A%84%E4%B8%AA%E6%95%B0/README.md)                                                                                     | `位运算`              | 简单 |
| [16](https://leetcode.cn/problems/shu-zhi-de-zheng-shu-ci-fang-lcof)                                 | [数值的整数次方](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9816.%20%E6%95%B0%E5%80%BC%E7%9A%84%E6%95%B4%E6%95%B0%E6%AC%A1%E6%96%B9/README.md)                                                                                         | `递归`                | 中等 |
| [17](https://leetcode.cn/problems/da-yin-cong-1dao-zui-da-de-nwei-shu-lcof)                          | [打印从 1 到最大的 n 位数](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9817.%20%E6%89%93%E5%8D%B0%E4%BB%8E1%E5%88%B0%E6%9C%80%E5%A4%A7%E7%9A%84n%E4%BD%8D%E6%95%B0/README.md)                                                           | `数学`                | 简单 |
| [18](https://leetcode.cn/problems/shan-chu-lian-biao-de-jie-dian-lcof)                               | [删除链表的节点](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9818.%20%E5%88%A0%E9%99%A4%E9%93%BE%E8%A1%A8%E7%9A%84%E8%8A%82%E7%82%B9/README.md)                                                                                         | `链表`                | 简单 |
| [19](https://leetcode.cn/problems/zheng-ze-biao-da-shi-pi-pei-lcof)                                  | [正则表达式匹配](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9819.%20%E6%AD%A3%E5%88%99%E8%A1%A8%E8%BE%BE%E5%BC%8F%E5%8C%B9%E9%85%8D/README.md)                                                                                         | `动态规划`            | 困难 |
| [20](https://leetcode.cn/problems/biao-shi-shu-zhi-de-zi-fu-chuan-lcof)                              | [表示数值的字符串](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9820.%20%E8%A1%A8%E7%A4%BA%E6%95%B0%E5%80%BC%E7%9A%84%E5%AD%97%E7%AC%A6%E4%B8%B2/README.md)                                                                              | `数学`                | 中等 |
| [21](https://leetcode.cn/problems/diao-zheng-shu-zu-shun-xu-shi-qi-shu-wei-yu-ou-shu-qian-mian-lcof) | [调整数组顺序使奇数位于偶数前面](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9821.%20%E8%B0%83%E6%95%B4%E6%95%B0%E7%BB%84%E9%A1%BA%E5%BA%8F%E4%BD%BF%E5%A5%87%E6%95%B0%E4%BD%8D%E4%BA%8E%E5%81%B6%E6%95%B0%E5%89%8D%E9%9D%A2/README.md) |                       | 简单 |
| [22](https://leetcode.cn/problems/lian-biao-zhong-dao-shu-di-kge-jie-dian-lcof)                      | [链表中倒数第 k 个节点](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9822.%20%E9%93%BE%E8%A1%A8%E4%B8%AD%E5%80%92%E6%95%B0%E7%AC%ACk%E4%B8%AA%E8%8A%82%E7%82%B9/README.md)                                                               | `链表`,`双指针`       | 简单 |
| [24](https://leetcode.cn/problems/fan-zhuan-lian-biao-lcof)                                          | [反转链表](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9824.%20%E5%8F%8D%E8%BD%AC%E9%93%BE%E8%A1%A8/README.md)                                                                                                                          | `链表`                | 简单 |
| [25](https://leetcode.cn/problems/he-bing-liang-ge-pai-xu-de-lian-biao-lcof)                         | [合并两个排序的链表](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9825.%20%E5%90%88%E5%B9%B6%E4%B8%A4%E4%B8%AA%E6%8E%92%E5%BA%8F%E7%9A%84%E9%93%BE%E8%A1%A8/README.md)                                                                   | `分治算法`            | 简单 |
| [26](https://leetcode.cn/problems/shu-de-zi-jie-gou-lcof)                                            | [树的子结构](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9826.%20%E6%A0%91%E7%9A%84%E5%AD%90%E7%BB%93%E6%9E%84/README.md)                                                                                                               | `树`                  | 中等 |
| [27](https://leetcode.cn/problems/er-cha-shu-de-jing-xiang-lcof)                                     | [二叉树的镜像](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9827.%20%E4%BA%8C%E5%8F%89%E6%A0%91%E7%9A%84%E9%95%9C%E5%83%8F/README.md)                                                                                                    | `树`                  | 简单 |
| [28](https://leetcode.cn/problems/dui-cheng-de-er-cha-shu-lcof)                                      | [对称的二叉树](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9828.%20%E5%AF%B9%E7%A7%B0%E7%9A%84%E4%BA%8C%E5%8F%89%E6%A0%91/README.md)                                                                                                    | `树`                  | 简单 |
| [29](https://leetcode.cn/problems/shun-shi-zhen-da-yin-ju-zhen-lcof)                                 | [顺时针打印矩阵](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9829.%20%E9%A1%BA%E6%97%B6%E9%92%88%E6%89%93%E5%8D%B0%E7%9F%A9%E9%98%B5/README.md)                                                                                         | `数组`                | 简单 |
| [30](https://leetcode.cn/problems/bao-han-minhan-shu-de-zhan-lcof)                                   | [包含 min 函数的栈](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9830.%20%E5%8C%85%E5%90%ABmin%E5%87%BD%E6%95%B0%E7%9A%84%E6%A0%88/README.md)                                                                                            | `栈`,`设计`           | 简单 |
| [31](https://leetcode.cn/problems/zhan-de-ya-ru-dan-chu-xu-lie-lcof)                                 | [栈的压入、弹出序列](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9831.%20%E6%A0%88%E7%9A%84%E5%8E%8B%E5%85%A5%E3%80%81%E5%BC%B9%E5%87%BA%E5%BA%8F%E5%88%97/README.md)                                                                   |                       | 中等 |
| [32 - I](https://leetcode.cn/problems/cong-shang-dao-xia-da-yin-er-cha-shu-lcof)                     | [从上到下打印二叉树](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9832%20-%20I.%20%E4%BB%8E%E4%B8%8A%E5%88%B0%E4%B8%8B%E6%89%93%E5%8D%B0%E4%BA%8C%E5%8F%89%E6%A0%91/README.md)                                                           | `树`,`广度优先搜索`   | 中等 |
| [32 - II](https://leetcode.cn/problems/cong-shang-dao-xia-da-yin-er-cha-shu-ii-lcof)                 | [从上到下打印二叉树 II](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9832%20-%20II.%20%E4%BB%8E%E4%B8%8A%E5%88%B0%E4%B8%8B%E6%89%93%E5%8D%B0%E4%BA%8C%E5%8F%89%E6%A0%91%20II/README.md)                                                  | `树`,`广度优先搜索`   | 简单 |
| [32 - III](https://leetcode.cn/problems/cong-shang-dao-xia-da-yin-er-cha-shu-iii-lcof)               | [从上到下打印二叉树 III](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9832%20-%20III.%20%E4%BB%8E%E4%B8%8A%E5%88%B0%E4%B8%8B%E6%89%93%E5%8D%B0%E4%BA%8C%E5%8F%89%E6%A0%91%20III/README.md)                                               | `树`,`广度优先搜索`   | 中等 |
| [33](https://leetcode.cn/problems/er-cha-sou-suo-shu-de-hou-xu-bian-li-xu-lie-lcof)                  | [二叉搜索树的后序遍历序列](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9833.%20%E4%BA%8C%E5%8F%89%E6%90%9C%E7%B4%A2%E6%A0%91%E7%9A%84%E5%90%8E%E5%BA%8F%E9%81%8D%E5%8E%86%E5%BA%8F%E5%88%97/README.md)                                  |                       | 中等 |
| [34](https://leetcode.cn/problems/er-cha-shu-zhong-he-wei-mou-yi-zhi-de-lu-jing-lcof)                | [二叉树中和为某一值的路径](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9834.%20%E4%BA%8C%E5%8F%89%E6%A0%91%E4%B8%AD%E5%92%8C%E4%B8%BA%E6%9F%90%E4%B8%80%E5%80%BC%E7%9A%84%E8%B7%AF%E5%BE%84/README.md)                                  | `树`,`深度优先搜索`   | 中等 |
| [35](https://leetcode.cn/problems/fu-za-lian-biao-de-fu-zhi-lcof)                                    | [复杂链表的复制](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9835.%20%E5%A4%8D%E6%9D%82%E9%93%BE%E8%A1%A8%E7%9A%84%E5%A4%8D%E5%88%B6/README.md)                                                                                         | `链表`                | 中等 |
| [36](https://leetcode.cn/problems/er-cha-sou-suo-shu-yu-shuang-xiang-lian-biao-lcof)                 | [二叉搜索树与双向链表](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9836.%20%E4%BA%8C%E5%8F%89%E6%90%9C%E7%B4%A2%E6%A0%91%E4%B8%8E%E5%8F%8C%E5%90%91%E9%93%BE%E8%A1%A8/README.md)                                                        | `分治算法`            | 中等 |
| [37](https://leetcode.cn/problems/xu-lie-hua-er-cha-shu-lcof)                                        | [序列化二叉树](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9837.%20%E5%BA%8F%E5%88%97%E5%8C%96%E4%BA%8C%E5%8F%89%E6%A0%91/README.md)                                                                                                    | `树`,`设计`           | 困难 |
| [38](https://leetcode.cn/problems/zi-fu-chuan-de-pai-lie-lcof)                                       | [字符串的排列](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9838.%20%E5%AD%97%E7%AC%A6%E4%B8%B2%E7%9A%84%E6%8E%92%E5%88%97/README.md)                                                                                                    | `回溯算法`            | 中等 |
| [39](https://leetcode.cn/problems/shu-zu-zhong-chu-xian-ci-shu-chao-guo-yi-ban-de-shu-zi-lcof)       | [数组中出现次数超过一半的数字](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9839.%20%E6%95%B0%E7%BB%84%E4%B8%AD%E5%87%BA%E7%8E%B0%E6%AC%A1%E6%95%B0%E8%B6%85%E8%BF%87%E4%B8%80%E5%8D%8A%E7%9A%84%E6%95%B0%E5%AD%97/README.md)            | `位运算`,`分治算法`   | 简单 |
| [40](https://leetcode.cn/problems/zui-xiao-de-kge-shu-lcof)                                          | [最小的 k 个数](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9840.%20%E6%9C%80%E5%B0%8F%E7%9A%84k%E4%B8%AA%E6%95%B0/README.md)                                                                                                           | `堆`,`分治算法`       | 简单 |
| [41](https://leetcode.cn/problems/shu-ju-liu-zhong-de-zhong-wei-shu-lcof)                            | [数据流中的中位数](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9841.%20%E6%95%B0%E6%8D%AE%E6%B5%81%E4%B8%AD%E7%9A%84%E4%B8%AD%E4%BD%8D%E6%95%B0/README.md)                                                                              | `堆`,`设计`           | 困难 |
| [42](https://leetcode.cn/problems/lian-xu-zi-shu-zu-de-zui-da-he-lcof)                               | [连续子数组的最大和](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9842.%20%E8%BF%9E%E7%BB%AD%E5%AD%90%E6%95%B0%E7%BB%84%E7%9A%84%E6%9C%80%E5%A4%A7%E5%92%8C/README.md)                                                                   | `分治算法`,`动态规划` | 简单 |
| [43](https://leetcode.cn/problems/1nzheng-shu-zhong-1chu-xian-de-ci-shu-lcof)                        | [1 ～ n 整数中 1 出现的次数](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9843.%201%EF%BD%9En%E6%95%B4%E6%95%B0%E4%B8%AD1%E5%87%BA%E7%8E%B0%E7%9A%84%E6%AC%A1%E6%95%B0/README.md)                                                        | `数学`                | 困难 |
| [44](https://leetcode.cn/problems/shu-zi-xu-lie-zhong-mou-yi-wei-de-shu-zi-lcof)                     | [数字序列中某一位的数字](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9844.%20%E6%95%B0%E5%AD%97%E5%BA%8F%E5%88%97%E4%B8%AD%E6%9F%90%E4%B8%80%E4%BD%8D%E7%9A%84%E6%95%B0%E5%AD%97/README.md)                                             | `数学`                | 中等 |
| [45](https://leetcode.cn/problems/ba-shu-zu-pai-cheng-zui-xiao-de-shu-lcof)                          | [把数组排成最小的数](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9845.%20%E6%8A%8A%E6%95%B0%E7%BB%84%E6%8E%92%E6%88%90%E6%9C%80%E5%B0%8F%E7%9A%84%E6%95%B0/README.md)                                                                   | `排序`                | 中等 |
| [46](https://leetcode.cn/problems/ba-shu-zi-fan-yi-cheng-zi-fu-chuan-lcof)                           | [把数字翻译成字符串](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9846.%20%E6%8A%8A%E6%95%B0%E5%AD%97%E7%BF%BB%E8%AF%91%E6%88%90%E5%AD%97%E7%AC%A6%E4%B8%B2/README.md)                                                                   |                       | 中等 |
| [47](https://leetcode.cn/problems/li-wu-de-zui-da-jie-zhi-lcof)                                      | [礼物的最大价值](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9847.%20%E7%A4%BC%E7%89%A9%E7%9A%84%E6%9C%80%E5%A4%A7%E4%BB%B7%E5%80%BC/README.md)                                                                                         | `动态规划`            | 中等 |
| [48](https://leetcode.cn/problems/zui-chang-bu-han-zhong-fu-zi-fu-de-zi-zi-fu-chuan-lcof)            | [最长不含重复字符的子字符串](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9848.%20%E6%9C%80%E9%95%BF%E4%B8%8D%E5%90%AB%E9%87%8D%E5%A4%8D%E5%AD%97%E7%AC%A6%E7%9A%84%E5%AD%90%E5%AD%97%E7%AC%A6%E4%B8%B2/README.md)                       | `哈希表`,`双指针`     | 中等 |
| [49](https://leetcode.cn/problems/chou-shu-lcof)                                                     | [丑数](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9849.%20%E4%B8%91%E6%95%B0/README.md)                                                                                                                                                | `数学`                | 中等 |
| [50](https://leetcode.cn/problems/di-yi-ge-zhi-chu-xian-yi-ci-de-zi-fu-lcof)                         | [第一个只出现一次的字符](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9850.%20%E7%AC%AC%E4%B8%80%E4%B8%AA%E5%8F%AA%E5%87%BA%E7%8E%B0%E4%B8%80%E6%AC%A1%E7%9A%84%E5%AD%97%E7%AC%A6/README.md)                                             | `哈希表`              | 简单 |
| [51](https://leetcode.cn/problems/shu-zu-zhong-de-ni-xu-dui-lcof)                                    | [数组中的逆序对](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9851.%20%E6%95%B0%E7%BB%84%E4%B8%AD%E7%9A%84%E9%80%86%E5%BA%8F%E5%AF%B9/README.md)                                                                                         |                       | 困难 |
| [52](https://leetcode.cn/problems/liang-ge-lian-biao-de-di-yi-ge-gong-gong-jie-dian-lcof)            | [两个链表的第一个公共节点](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9852.%20%E4%B8%A4%E4%B8%AA%E9%93%BE%E8%A1%A8%E7%9A%84%E7%AC%AC%E4%B8%80%E4%B8%AA%E5%85%AC%E5%85%B1%E8%8A%82%E7%82%B9/README.md)                                  | `链表`                | 简单 |
| [53 - I](https://leetcode.cn/problems/zai-pai-xu-shu-zu-zhong-cha-zhao-shu-zi-lcof)                  | [在排序数组中查找数字 I](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9853%20-%20I.%20%E5%9C%A8%E6%8E%92%E5%BA%8F%E6%95%B0%E7%BB%84%E4%B8%AD%E6%9F%A5%E6%89%BE%E6%95%B0%E5%AD%97%20I/README.md)                                          | `数组`,`二分查找`     | 简单 |
| [53 - II](https://leetcode.cn/problems/que-shi-de-shu-zi-lcof)                                       | [0 ～ n-1 中缺失的数字](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9853%20-%20II.%200%EF%BD%9En-1%E4%B8%AD%E7%BC%BA%E5%A4%B1%E7%9A%84%E6%95%B0%E5%AD%97/README.md)                                                                     | `数组`,`二分查找`     | 简单 |
| [54](https://leetcode.cn/problems/er-cha-sou-suo-shu-de-di-kda-jie-dian-lcof)                        | [二叉搜索树的第 k 大节点](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9854.%20%E4%BA%8C%E5%8F%89%E6%90%9C%E7%B4%A2%E6%A0%91%E7%9A%84%E7%AC%ACk%E5%A4%A7%E8%8A%82%E7%82%B9/README.md)                                                    | `树`                  | 简单 |
| [55 - I](https://leetcode.cn/problems/er-cha-shu-de-shen-du-lcof)                                    | [二叉树的深度](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9855%20-%20I.%20%E4%BA%8C%E5%8F%89%E6%A0%91%E7%9A%84%E6%B7%B1%E5%BA%A6/README.md)                                                                                            | `树`,`深度优先搜索`   | 简单 |
| [55 - II](https://leetcode.cn/problems/ping-heng-er-cha-shu-lcof)                                    | [平衡二叉树](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9855%20-%20II.%20%E5%B9%B3%E8%A1%A1%E4%BA%8C%E5%8F%89%E6%A0%91/README.md)                                                                                                      | `树`,`深度优先搜索`   | 简单 |
| [56 - I](https://leetcode.cn/problems/shu-zu-zhong-shu-zi-chu-xian-de-ci-shu-lcof)                   | [数组中数字出现的次数](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9856%20-%20I.%20%E6%95%B0%E7%BB%84%E4%B8%AD%E6%95%B0%E5%AD%97%E5%87%BA%E7%8E%B0%E7%9A%84%E6%AC%A1%E6%95%B0/README.md)                                                |                       | 中等 |
| [56 - II](https://leetcode.cn/problems/shu-zu-zhong-shu-zi-chu-xian-de-ci-shu-ii-lcof)               | [数组中数字出现的次数 II](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9856%20-%20II.%20%E6%95%B0%E7%BB%84%E4%B8%AD%E6%95%B0%E5%AD%97%E5%87%BA%E7%8E%B0%E7%9A%84%E6%AC%A1%E6%95%B0%20II/README.md)                                       |                       | 中等 |
| [57](https://leetcode.cn/problems/he-wei-sde-liang-ge-shu-zi-lcof)                                   | [和为 s 的两个数字](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9857.%20%E5%92%8C%E4%B8%BAs%E7%9A%84%E4%B8%A4%E4%B8%AA%E6%95%B0%E5%AD%97/README.md)                                                                                     |                       | 简单 |
| [57 - II](https://leetcode.cn/problems/he-wei-sde-lian-xu-zheng-shu-xu-lie-lcof)                     | [和为 s 的连续正数序列](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9857%20-%20II.%20%E5%92%8C%E4%B8%BAs%E7%9A%84%E8%BF%9E%E7%BB%AD%E6%AD%A3%E6%95%B0%E5%BA%8F%E5%88%97/README.md)                                                      |                       | 简单 |
| [58 - I](https://leetcode.cn/problems/fan-zhuan-dan-ci-shun-xu-lcof)                                 | [翻转单词顺序](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9858%20-%20I.%20%E7%BF%BB%E8%BD%AC%E5%8D%95%E8%AF%8D%E9%A1%BA%E5%BA%8F/README.md)                                                                                            | `字符串`              | 简单 |
| [58 - II](https://leetcode.cn/problems/zuo-xuan-zhuan-zi-fu-chuan-lcof)                              | [左旋转字符串](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9858%20-%20II.%20%E5%B7%A6%E6%97%8B%E8%BD%AC%E5%AD%97%E7%AC%A6%E4%B8%B2/README.md)                                                                                           | `字符串`              | 简单 |
| [59 - I](https://leetcode.cn/problems/hua-dong-chuang-kou-de-zui-da-zhi-lcof)                        | [滑动窗口的最大值](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9859%20-%20I.%20%E6%BB%91%E5%8A%A8%E7%AA%97%E5%8F%A3%E7%9A%84%E6%9C%80%E5%A4%A7%E5%80%BC/README.md)                                                                      | `栈`                  | 困难 |
| [59 - II](https://leetcode.cn/problems/dui-lie-de-zui-da-zhi-lcof)                                   | [队列的最大值](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9859%20-%20II.%20%E9%98%9F%E5%88%97%E7%9A%84%E6%9C%80%E5%A4%A7%E5%80%BC/README.md)                                                                                           | `栈`                  | 中等 |
| [60](https://leetcode.cn/problems/nge-tou-zi-de-dian-shu-lcof)                                       | [n 个骰子的点数](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9860.%20n%E4%B8%AA%E9%AA%B0%E5%AD%90%E7%9A%84%E7%82%B9%E6%95%B0/README.md)                                                                                                 |                       | 中等 |
| [61](https://leetcode.cn/problems/bu-ke-pai-zhong-de-shun-zi-lcof)                                   | [扑克牌中的顺子](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9861.%20%E6%89%91%E5%85%8B%E7%89%8C%E4%B8%AD%E7%9A%84%E9%A1%BA%E5%AD%90/README.md)                                                                                         |                       | 简单 |
| [62](https://leetcode.cn/problems/yuan-quan-zhong-zui-hou-sheng-xia-de-shu-zi-lcof)                  | [圆圈中最后剩下的数字](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9862.%20%E5%9C%86%E5%9C%88%E4%B8%AD%E6%9C%80%E5%90%8E%E5%89%A9%E4%B8%8B%E7%9A%84%E6%95%B0%E5%AD%97/README.md)                                                        |                       | 简单 |
| [63](https://leetcode.cn/problems/gu-piao-de-zui-da-li-run-lcof)                                     | [股票的最大利润](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9863.%20%E8%82%A1%E7%A5%A8%E7%9A%84%E6%9C%80%E5%A4%A7%E5%88%A9%E6%B6%A6/README.md)                                                                                         | `动态规划`            | 中等 |
| [64](https://leetcode.cn/problems/qiu-12n-lcof)                                                      | [求 1+2+…+n](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9864.%20%E6%B1%821%2B2%2B%E2%80%A6%2Bn/README.md)                                                                                                                              |                       | 中等 |
| [65](https://leetcode.cn/problems/bu-yong-jia-jian-cheng-chu-zuo-jia-fa-lcof)                        | [不用加减乘除做加法](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9865.%20%E4%B8%8D%E7%94%A8%E5%8A%A0%E5%87%8F%E4%B9%98%E9%99%A4%E5%81%9A%E5%8A%A0%E6%B3%95/README.md)                                                                   |                       | 简单 |
| [66](https://leetcode.cn/problems/gou-jian-cheng-ji-shu-zu-lcof)                                     | [构建乘积数组](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9866.%20%E6%9E%84%E5%BB%BA%E4%B9%98%E7%A7%AF%E6%95%B0%E7%BB%84/README.md)                                                                                                    |                       | 中等 |
| [67](https://leetcode.cn/problems/ba-zi-fu-chuan-zhuan-huan-cheng-zheng-shu-lcof)                    | [把字符串转换成整数](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9867.%20%E6%8A%8A%E5%AD%97%E7%AC%A6%E4%B8%B2%E8%BD%AC%E6%8D%A2%E6%88%90%E6%95%B4%E6%95%B0/README.md)                                                                   | `数学`,`字符串`       | 中等 |
| [68 - I](https://leetcode.cn/problems/er-cha-sou-suo-shu-de-zui-jin-gong-gong-zu-xian-lcof)          | [二叉搜索树的最近公共祖先](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9868%20-%20I.%20%E4%BA%8C%E5%8F%89%E6%90%9C%E7%B4%A2%E6%A0%91%E7%9A%84%E6%9C%80%E8%BF%91%E5%85%AC%E5%85%B1%E7%A5%96%E5%85%88/README.md)                          | `树`                  | 简单 |
| [68 - II](https://leetcode.cn/problems/er-cha-shu-de-zui-jin-gong-gong-zu-xian-lcof)                 | [二叉树的最近公共祖先](/lcof/%E9%9D%A2%E8%AF%95%E9%A2%9868%20-%20II.%20%E4%BA%8C%E5%8F%89%E6%A0%91%E7%9A%84%E6%9C%80%E8%BF%91%E5%85%AC%E5%85%B1%E7%A5%96%E5%85%88/README.md)                                               | `树`                  | 简单 |

## 版权

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## 许可证

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