LeetCode 高频题

Fib
strstr
Reverse a linkedlist/integer/string
Matrix
-rotate matrix/rectangle
-move a matrix
-spiral matrix I II
Anagrams(find all unique/all non-unique) Hashtable





Two Pointers:
- 2/3/4 sums, 3 sum closet, combination sum
-Sort colors
-Remove duplicates from Array
-Remove duplicates from Sorted Array
-Remove duplicates from Linked List


Recursion:
-N-Queens I, II
-Generate Parentheses


Bit-Operation
-Single Number
-Single Number II
-O(1) check whether a number is power of 2




Big Date Google
-Add binary
-Add two numbers
-Multiply strings
-Plus one






边界条件 Linkedin 沟通
Pow(x,n) 
Sqrt(x)
Valid Number




Data Structure Java source code
HashMap/HashSet/Hashtable/LinkedHashMap, ArrayList, Comparator, Iterator


-Implement HashMap
-Implement peek() function for iterator
-LRU cache, implement LinkedHashMap
-Singleton






Stack & Queue
-Evaulate reverse polish notation
-Vlaid Parentheses
-Longest vaid parentheses
-Min stack
-Two stack implements a queue






Best Time to buy & sell stocks I, II, III
Maximum subarray
Trailing number of 0s
Linkedlist Cycle I, II


DP
Unique Path I, II  机器人走迷宫
数学方法
代码实现



如何做LeetCode？

1. Computer：完成题目，写 test cases
2. Paper：重做一遍
3. Computer: 优化代码风格、删除冗余代码
4. Paper: 默写