排序map、pq、stack。固定 递归 贪心 开关 二分 滑动窗口（固递贪开二滑）

摘要： Design and implement an iterator to flatten a 2d vector. It should support the following operations: next and hasNext. Example:Vector2D iterator = new 阅读全文

摘要： 【假设只有一周的复习时间，抱佛脚思路】我不得不说，算法题的内容真是太多了：浏览一遍都老费力了。宛如GRE。 数组、链表、字符串、q、stack、hash：有很多小技巧的题目，但是也懒得去看了。临时看看基本的一些翻转就行了 快速排序、n sum：都是固定的模板，临时看看就行了前向窗口：写了--【】设计 阅读全文

摘要： Given a string containing digits from 2-9 inclusive, return all possible letter combinations that the number could represent. A mapping of digit to le 阅读全文

摘要： Given a non-empty 2D array grid of 0's and 1's, an island is a group of 1's (representing land) connected 4-directionally (horizontal or vertical.) Yo 阅读全文

摘要： Given a 2D board and a word, find if the word exists in the grid. The word can be constructed from letters of a sequentially adjacent cells, where "ad 阅读全文

摘要： Given a 2d grid map of '1's (land) and '0's (water), count the number of islands. An island is surrounded by water and is formed by connecting adjacen 阅读全文

摘要： Given a non-empty 2D array grid of 0's and 1's, an island is a group of 1's (representing land) connected 4-directionally (horizontal or vertical.) Yo 阅读全文

摘要： Given a string s, partition s such that every substring of the partition is a palindrome. Return all possible palindrome partitioning of s. Example: I 阅读全文

摘要： Given a collection of candidate numbers (candidates) and a target number (target), find all unique combinations in candidates where the candidate numb 阅读全文

摘要： Given a set of candidate numbers (candidates) (without duplicates) and a target number (target), find all unique combinations in candidates where the 阅读全文