xinyu04

摘要： There is a long and thin painting that can be represented by a number line. You are given a 0-indexed 2D integer array paint of length n, where paint[ 阅读全文

摘要： Given two strings s1 and s2, return true if s2 contains a permutation of s1, or false otherwise. In other words, return true if one of s1's permutatio 阅读全文

摘要： Given a string s, find the length of the longest substring without repeating characters. Solution 求最长的不重复子串。我们利用左右两个指针来模拟端点，然后用 $set$ 来记录出现过的字符。当出现重复的 阅读全文

摘要： You are given an integer array prices where prices[i] is the price of a given stock on the $i$th day. On each day, you may decide to buy and/or sell t 阅读全文

摘要： You are given an array prices where prices[i] is the price of a given stock on the $i$th day. You want to maximize your profit by choosing a single da 阅读全文