随笔分类 -  LeetCode

LeetCode Convert Sorted Array to Binary Search Tree
摘要：Given an array where elements are sorted in ascending order, convert it to a height balanced BST.解题思路：根据递增序列，求平衡二叉查找树，根据平衡二叉查找树的性质，其左右都是二叉查找树，用递归可以比较轻... 阅读全文
posted @ 2014-12-29 21:59 ElephantKing 阅读(116) 评论(0) 推荐(0)
LeetCode Unique Binary Search Trees
摘要：Givenn, how many structurally uniqueBST's(binary search trees) that store values 1...n?For example,Givenn= 3, there are a total of 5 unique BST's. 1... 阅读全文
posted @ 2014-12-29 21:45 ElephantKing 阅读(106) 评论(0) 推荐(0)
LeetCode Longest Substring Without Repeating Characters
摘要：Given a string, find the length of the longest substring without repeating characters. For example, the longest substring without repeating letters fo... 阅读全文
posted @ 2014-12-14 22:55 ElephantKing 阅读(108) 评论(0) 推荐(0)
LeetCode Remove Duplicates from Sorted List II
摘要：Given a sorted linked list, delete all nodes that have duplicate numbers, leaving onlydistinctnumbers from the original list.For example,Given1->2->3-... 阅读全文
posted @ 2014-12-13 15:16 ElephantKing 阅读(123) 评论(0) 推荐(0)
LeetCode Convert Sorted List to Binary Search Tree
摘要：Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST.解题思路：找到链表的中点，作为根，前端作为左子树，后端作为右子树，并对前后做递归操... 阅读全文
posted @ 2014-12-13 12:49 ElephantKing 阅读(116) 评论(0) 推荐(0)
LeetCode Linked List Cycle II
摘要：Given a linked list, return the node where the cycle begins. If there is no cycle, returnnull.Follow up:Can you solve it without using extra space?首先指... 阅读全文
posted @ 2014-12-12 00:57 ElephantKing 阅读(105) 评论(0) 推荐(0)
LeetCode Linked List Cycle
摘要：Given a linked list, determine if it has a cycle in it.Follow up:Can you solve it without using extra space?解题思路：突发奇想，脑洞大开。回路，自然是走到已经走过的地方，如何知道这个地方已经走... 阅读全文
posted @ 2014-12-11 23:16 ElephantKing 阅读(110) 评论(0) 推荐(0)
LeetCode First Missing Positive
摘要：Given an unsorted integer array, find the first missing positive integer.For example,Given[1,2,0]return3,and[3,4,-1,1]return2.Your algorithm should ru... 阅读全文
posted @ 2014-12-10 12:23 ElephantKing 阅读(88) 评论(0) 推荐(0)
LeetCode Merge Intervals
摘要：Given a collection of intervals, merge all overlapping intervals.For example,Given[1,3],[2,6],[8,10],[15,18],return[1,6],[8,10],[15,18].解题思路：先按左端点排序，然... 阅读全文
posted @ 2014-12-10 12:14 ElephantKing 阅读(96) 评论(0) 推荐(0)
LeetCode Longest Consecutive Sequence
摘要：Given an unsorted array of integers, find the length of the longest consecutive elements sequence.For example,Given[100, 4, 200, 1, 3, 2],The longest ... 阅读全文
posted @ 2014-12-10 00:58 ElephantKing 阅读(91) 评论(0) 推荐(0)
LeetCode Find Peak Element
摘要：A peak element is an element that is greater than its neighbors.Given an input array wherenum[i] ≠ num[i+1], find a peak element and return its index.... 阅读全文
posted @ 2014-12-08 20:22 ElephantKing 阅读(142) 评论(0) 推荐(0)
LeetCode Edit Distance
摘要：Given two wordsword1andword2, find the minimum number of steps required to convertword1toword2. (each operation is counted as 1 step.)You have the fol... 阅读全文
posted @ 2014-12-06 15:57 ElephantKing 阅读(105) 评论(0) 推荐(0)
LeetCode Unique Paths
摘要：A robot is located at the top-left corner of amxngrid (marked 'Start' in the diagram below).The robot can only move either down or right at any point ... 阅读全文
posted @ 2014-12-05 14:24 ElephantKing 阅读(94) 评论(0) 推荐(0)
LeetCode Minimum Path Sum
摘要：class Solution {public: int min(int a, int b) { return a>b?b:a; } int getMin(vector > grid, int m, int n) { int current =... 阅读全文
posted @ 2014-12-05 14:20 ElephantKing 阅读(138) 评论(0) 推荐(0)
LeetCode Container With Most Water
摘要：Givennnon-negative integersa1,a2, ...,an, where each represents a point at coordinate (i,ai).nvertical lines are drawn such that the two endpoints of ... 阅读全文
posted @ 2014-12-04 20:10 ElephantKing 阅读(114) 评论(0) 推荐(0)
LeetCode 3Sum Closest
摘要：Given an arraySofnintegers, find three integers inSsuch that the sum is closest to a given number, target. Return the sum of the three integers. You m... 阅读全文
posted @ 2014-12-03 19:46 ElephantKing 阅读(138) 评论(1) 推荐(0)
LeetCode Pascal's Triangle II
摘要：Pascal's Triangle IIGiven an indexk, return thekthrow of the Pascal's triangle.For example, givenk= 3,Return[1,3,3,1].Note:Could you optimize your alg... 阅读全文
posted @ 2014-12-02 20:28 ElephantKing 阅读(101) 评论(0) 推荐(0)
LeetCode Intersection of Two Linked Lists
摘要：Write a program to find the node at which the intersection of two singly linked lists begins.For example, the following two linked lists:A: a... 阅读全文
posted @ 2014-12-01 14:54 ElephantKing 阅读(121) 评论(0) 推荐(0)
LeetCode Binary Tree Level Order Traversal
摘要：Given a binary tree, return thelevel ordertraversal of its nodes' values. (ie, from left to right, level by level).For example:Given binary tree{3,9,2... 阅读全文
posted @ 2014-12-01 13:49 ElephantKing 阅读(121) 评论(0) 推荐(0)