LeetCode - Binary Search 总结
二分法简单但是边界值十分容易出错, 时间复杂度为O(log n)
mid = right + (left - right) / 2 防止left right 都大时候溢出
二分法剖析：Binary Search 二分搜索法 C++
bold - high frequency top 5
第一类 基本用法
Search Insert Position [easy, 2]
Find First and Last Position of Element in Sorted Array [medium, 2]
First Bad Version [easy, 2]
Find Peak Element [medium, 2]
Heaters [easy, 2] (解法二，第一个不小于)
Closest Binary Search Tree Value
Median of Two Sorted Arrays [hard, 1]
第二类 数学相关
Sqrt(X) [easy, 2]
Valid Perfect Square [easy, 3] (解法二，==)
Pow(x, n) [median, 1]
Arranging Coins [easy, 2] (数列，小心overflow)
第三类 2D binary search
Search a 2d Matrix [median, 2], II[median, 2] (not BS)
第四类 sorted or rotated array
Search in Rotated Sorted Array [median, 1], II [median, 2] (duplicated allowed)
Find Minimum in Rotated Sorted Array, II (duplicated allowed)
利用Binary Search维护Longest Increasing Substring
维护一个vector，每一个元素代表 increasing substring position i 上最小的数
update: 小于首元素代替，大于末元素加在末尾，大于首元素小于末元素代替第一个比它大的元素
注：这个维护的vector并非最后的increasing substring，只是元素个数相同
Longest Increasing Subsequence [medium, 2]
Russian Doll Envelopes [hard, 2] (上面的升级版)
还想练手：
Increasing Triplet Subsequence [medium, 3]
未归类
Find Smallest Letter Greater Than Target
Find Kth Smallest Pair Distance
Find K Closest Elements
Find the Duplicate Number
Kth Smallest Number in Multiplication Table
Kth Smallest Element in a BST
Kth Smallest Element in a Sorted Matrix
Count Complete Tree Nodes
Divide Two Integers
Find Right Interval
4Sum II
Maximum Length of Repeated Subarray
Minimum Size Subarray Sum
Max Sum of Rectangle No Larger Than K [hard, 3]
Split Array Largest Sum
Kth Smallest Element in a Sorted Matrix
Count of Smaller Numbers After Self
Reference:
https://lefttree.gitbooks.io/leetcode-categories/BinarySearch/binarySearch.html
https://blog.csdn.net/linhuanmars/article/details/31354941
https://zxth93.github.io/2017/11/20/LeetCode-binary-search类总结/index.html