leetcode - 随笔分类 - Tiny-Box

[leetcode] 21. Implement strStr()

摘要：这个题目是典型的KMP算法，当然也可以试试BM，当然有关KMP和BM的介绍阮一峰曾经写过比较好的科普，然后july也有讲解，不过那个太长了。先放题目吧： Implement strStr(). Returns the index of the first occurrence of needle in haystack, or -1 if needle is not part of hays... 阅读全文

posted @ 2014-12-02 15:43 Tiny-Box 阅读(169) 评论(0) 推荐(0)

[leetcode] 20. Valid Sudoku

摘要：这道题目被放在的简单的类别里是有原因的，题目如下： Determine if a Sudoku is valid, according to: Sudoku Puzzles - The Rules. The Sudoku board could be partially filled, where empty cells are filled with the character '.'. A... 阅读全文

posted @ 2014-12-02 15:19 Tiny-Box 阅读(168) 评论(0) 推荐(0)

[leetcode] 19. Count and Say

摘要：这个还是一开始没读懂题目，题目如下：The count-and-say sequence is the sequence of integers beginning as follows:1, 11, 21, 1211, 111221, ...1 is read off as "one 1" or ... 阅读全文

posted @ 2014-11-26 00:04 Tiny-Box 阅读(184) 评论(0) 推荐(0)

[leetcode] 18. Length of Last Word

摘要：这个题目很简单，给一个字符串，然后返回最后一个单词的长度就行。题目如下： Given a string s consists of upper/lower-case alphabets and empty space characters ' ', return the length of last word in the string. If the last word does not ex... 阅读全文

posted @ 2014-11-25 23:55 Tiny-Box 阅读(137) 评论(0) 推荐(0)

[leetcode] 17. Merge Two Sorted Lists

摘要：这个非常简单的题目，题目如下： Merge two sorted linked lists and return it as a new list. The new list should be made by splicing together the nodes of the first two lists. 就是算导里面的第一个算法讲解，但是我的C++水平实在太渣，所以对于链表的操作很蠢，... 阅读全文

posted @ 2014-11-24 23:30 Tiny-Box 阅读(183) 评论(0) 推荐(0)

[leetcode] 16. Add Binary

摘要：这个题目相对有点奇怪，题目如下： Given two binary strings, return their sum (also a binary string). For example, a = "11" b = "1" Return "100". 可能是我思路的问题吧，我之前是在考虑先将string转成int或者double，然后将二进制转为十进制进行计算，最后再将这个十进制转为二进... 阅读全文

posted @ 2014-11-24 23:26 Tiny-Box 阅读(195) 评论(0) 推荐(0)

[leetcode] 15. Plus One

摘要：这道题其实让我意识到了我的英文水平还有待加强。。。。题目如下：Given a non-negative number represented as an array of digits, plus one to the number.The digits are stored such that t... 阅读全文

posted @ 2014-11-23 22:59 Tiny-Box 阅读(171) 评论(0) 推荐(0)

[leetcode] 14. Climbing Stairs

摘要：这道题leetcode上面写着是DP问题，问题是我一开始写了个简单的递归结果直接超时，所以没办法只好拿迭代来做了。题目如下： You are climbing a stair case. It takes n steps to reach to the top. Each time you can either climb 1 or 2 steps. In how many distinct w... 阅读全文

posted @ 2014-11-23 22:50 Tiny-Box 阅读(210) 评论(0) 推荐(0)

[leetcode] 13. Remove Duplicates from Sorted List

摘要：这个题目其实不难的，主要是我C++的水平太差了，链表那里绊了好久，但是又不像用python，所以还是强行上了。题目如下： Given a sorted linked list, delete all duplicates such that each element appear only once. For example, Given 1->1->2, return 1->2. Give... 阅读全文

posted @ 2014-11-22 16:37 Tiny-Box 阅读(132) 评论(0) 推荐(0)

[leetcode] 12. Merge Sorted Array

摘要：这道题的无聊之处在于题目其实给了一些很奇怪的测试用例。比如他会给一些空的数组来，但是这个是不科学的，因为在C++中不允许定义一个空的列表，我们用的又不是那种糙又快的python，所以在这里我遇到了一些问题，后来还是解决了。这道题题目如下：Given two sorted integer arrays... 阅读全文

posted @ 2014-11-20 22:56 Tiny-Box 阅读(127) 评论(0) 推荐(0)

[leetcode] 11. Same Tree

摘要：因为我刷题是难度不是按发布日期，所以就有可能遇到这种情况，比如这个。。。Given two binary trees, write a function to check if they are equal or not.Two binary trees are considered equal i... 阅读全文

posted @ 2014-11-18 13:40 Tiny-Box 阅读(116) 评论(0) 推荐(0)

[leetcode] 10. Symmetric Tree

摘要：这次我觉得我的智商太低，想了很久才写出来。题目是让求镜像二叉树判断，题目如下：Given a binary tree, check whether it is a mirror of itself (ie, symmetric around its center).For example, this... 阅读全文

posted @ 2014-11-18 12:57 Tiny-Box 阅读(155) 评论(0) 推荐(0)

[leetcode] 9. Binary Tree Level Order Traversal

摘要：跟第七题一样，把最后的输出顺序换一下就行。。。Given a binary tree, return the level order traversal of its nodes' values. (ie, from left to right, level by level).For exampl... 阅读全文

posted @ 2014-11-15 20:59 Tiny-Box 阅读(118) 评论(0) 推荐(0)

[leetcode] 8. Maximum Depth of Binary Tree

摘要：可能是因为我是按难度顺序刷的原因，这个其实在之前的几道题里面已经写过了。题目如下： Given a binary tree, find its maximum depth. The maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf nod... 阅读全文

posted @ 2014-11-15 20:53 Tiny-Box 阅读(100) 评论(0) 推荐(0)

[leetcode] 7. Binary Tree Level Order Traversal II

摘要：这次相对来讲复杂点，题目如下： Given a binary tree, return the bottom-up level order traversal of its nodes' values. (ie, from left to right, level by level from leaf to root). For example:Given binary tree {3,9,... 阅读全文

posted @ 2014-11-15 00:44 Tiny-Box 阅读(99) 评论(0) 推荐(0)

[leetcode] 6. Balanced Binary Tree

摘要：这个题目纠结了一会儿，终于从二叉树转化到AVL了。题目如下：Given a binary tree, determine if it is height-balanced.For this problem, a height-balanced binary tree is defined as a ... 阅读全文

posted @ 2014-11-13 11:18 Tiny-Box 阅读(129) 评论(0) 推荐(0)

[leetcode] 5. Minimum Depth of Binary Tree

摘要：二叉树基本功练习题，题目如下：Given a binary tree, find its minimum depth.The minimum depth is the number of nodes along the shortest path from the root node down to... 阅读全文

posted @ 2014-11-12 19:43 Tiny-Box 阅读(81) 评论(0) 推荐(0)

[leetcode] 4. Path Sum

摘要：终于到了二叉树。题目如下：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... 阅读全文

posted @ 2014-11-11 23:45 Tiny-Box 阅读(124) 评论(0) 推荐(0)

[leetcode] 3. Pascal's Triangle

摘要：第三道还是帕斯卡三角，这个是要求正常输出，题目如下：Given numRows, generate the first numRows of Pascal's triangle.For example, given numRows = 5, Return[ [1], [1,1], ... 阅读全文

posted @ 2014-11-11 09:28 Tiny-Box 阅读(130) 评论(0) 推荐(0)

[leetcode] 2. Pascal's Triangle II

摘要：我是按难度往下刷的，第二道是帕斯卡三角形二。简单易懂，题目如下：Given an index k, return the kth row of the Pascal's triangle.For example, given k = 3, Return [1,3,3,1].Note: Could y... 阅读全文

posted @ 2014-11-11 00:34 Tiny-Box 阅读(131) 评论(0) 推荐(0)

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随笔分类 - leetcode