原创 【leetcode】24. Swap Nodes in Pairs
Given a linked list, swap every two adjacent nodes and return its head. You may not modify the values in the list's nod
2019-02-27 13:09:18
原创 【leetcode】25. Reverse Nodes in k-Group
Given a linked list, reverse the nodes of a linked list k at a time and return its modified list. k is a positive integ
2019-02-27 13:09:18
原创 【leetcode】383. Ransom Note
Given an arbitrary ransom note string and another string containing letters from all the magazines, write a function th
2019-02-20 03:14:53
原创 【leetcode】263. Ugly Number
Write a program to check whether a given number is an ugly number. Ugly numbers are positive numbers whose prime factor
2019-02-16 20:36:54
原创 【leetcode】204. Count Primes
Count the number of prime numbers less than a non-negative number, n. Example: Input: 10 Output: 4 Explanation: There
2019-02-16 20:36:54
原创 【leetcode】240. Search a 2D Matrix II
Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties: In
2019-02-16 20:36:54
1
原创 【leetcode】894. All Possible Full Binary Trees
A full binary tree is a binary tree where each node has exactly 0 or 2 children. Return a list of all possible full bin
2019-02-14 13:09:56
2
原创 【leetcode】513. Find Bottom Left Tree Value
Given a binary tree, find the leftmost value in the last row of the tree. Example 1: Input: 2 / \ 1 3 Out
2019-02-14 13:09:56
原创 【leetcode】515. Find Largest Value in Each Tree Row
You need to find the largest value in each row of a binary tree. Example: Input: 1 / \ 3
2019-02-14 13:09:56
原创 【leetcode】779. K-th Symbol in Grammar
On the first row, we write a 0. Now in every subsequent row, we look at the previous row and replace each occurrence of
2019-02-14 13:09:45
原创 【leetcode】77. Combinations
Given two integers n and k, return all possible combinations of k numbers out of 1 ... n. Example: Input: n = 4, k = 2
2019-02-12 01:21:09
原创 【leetcode】3. Longest Substring Without Repeating Characters
Given a string, find the length of the longest substring without repeating characters. Example 1: Input: "abcabcbb" Ou
2019-02-12 01:21:09
2
原创 【leetcode】48. Rotate Image
You are given an n x n 2D matrix representing an image. Rotate the image by 90 degrees (clockwise). Note: You have to r
2019-02-12 01:21:08
2
原创 【leetcode】784. Letter Case Permutation
Given a string S, we can transform every letter individually to be lowercase or uppercase to create another string. Re
2019-02-12 01:21:08
1
原创 229. Majority Element II
Given an integer array of size n, find all elements that appear more than ⌊ n/3 ⌋ times. Note: The algorithm should run
2019-02-12 01:21:08