392. Is Subsequence (Easy)
Given a string s and a string t, check if s is subsequence of t.
You may assume that there is only lower case English letters in both s and t. t is potentially a very long…
186. Reverse Words in a String II(Easy)
Given an input string, reverse the string word by word. A word is defined as a sequence of non-space characters.
80. Remove Duplicates from Sorted Array II (Medium)
Given a sorted array nums, remove the duplicates in-place such that duplicates appeared at most twice and return the new…
028. Implement strStr()(Easy)
Implement strStr().
Return the index of the first occurrence of needle in haystack, or -1 if needle is not part of haystack.
309. Best Time to Buy and Sell Stock with Cooldown (Medium)
Say you have an array for which the ith element is the price of a given stock on day i.
169. Majority Element (Easy)
Given an array of size n, find the majority element. The majority element is the element that appears more than ⌊ n/2 ⌋ times.
⌊ n/2 ⌋
273. Integer to English Words (Hard)
Convert a non-negative integer to its english words representation. Given input is guaranteed to be less than 231–1((2的31次方)-1).
334. Increasing Triplet Subsequence (Medium)
Given an unsorted array return whether an increasing subsequence of length 3 exists or not in the array.
229. Majority Element II (Medium)
Given an integer array of size n, find all elements that appear more than ⌊ n/3 ⌋ times.
⌊ n/3 ⌋
42. Trapping Rain Water (Hard)
Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it is able to trap after raining.
