[Leetcode] Best Time to Buy and Sell Stock I,II,III,IV

Best Time to Buy and Sell Stock I 题意:用一个数组表示股票每天的价格,数组的第i个数表示股票在第i天的价格. 如果只允许进行一次交易,也就是说只允许买一支股票并卖掉,求最大的收益. 分析:动态规划法.从前向后遍历数组,记录当前出现过的最低价格,作为买入价格,并计算以当天价格出售的收益,作为可能的最大收益,整个遍历过程中,出现过的最大收益就是所求. 代码:时间O(n),空间O(1). Best Time to Buy and Sell Stock II 题目:用一

1. Best Time to Buy and Sell Stock I 题目链接 题目要求: Say you have an array for which the ith element is the price of a given stock on day i. If you were only permitted to complete at most one transaction (ie, buy one and sell one share of the stock), desi

买卖股票系列 && Subarray 相关题目: Best Time to Buy and Sell Stock I && II && III (IV 单独开贴) Maximum Subarray I && II 为什么这些我要总结到一起呢?因为思路基本一致. 题目简略: 买卖股票1: 一次买卖,利润最大. 买卖股票2: N次买卖,利润最大. 买卖股票3: 2次不重叠的买卖,利润最大. Maximum Subarray: Given an a

一个系列三道题,我都不会做,google之答案.过了两道,第三道看不懂,放置,稍后继续. 一.Best Time to Buy and Sell Stock I 题目:一个数组表示一支股票的价格变换.要求只买卖一次,获得最大收益. 思路:一开始我认为是寻找最大.最小值,但由于最大值不一定总是出现在最小值的后面,因此WA. 参考思路:DP.对第i个价格,减去前i-1个价格中的最小值(保证该收益是在第i个价格卖出的最大收益),其收益与之前获得的最大收益相比. 代码: 1 public int max

题目1:Best Time to Buy and Sell Stock Say you have an array for which the ith element is the price of a given stock on day i. If you were only permitted to complete at most one transaction (ie, buy one and sell one share of the stock), design an algori

1.  String to Integer (atoi) Implement atoi to convert a string to an integer. Hint: Carefully consider all possible input cases. If you want a challenge, please do not see below and ask yourself what are the possible input cases. Notes: It is inte

Best Time to Buy and Sell Stock Say you have an array for which the ith element is the price of a given stock on day i. If you were only permitted to complete at most one transaction (ie, buy one and sell one share of the stock), design an algorithm

Best Time to Buy and Sell Stock I 只能作一次操作时:维护preMin记录之前出现的最小值 代码如下: int maxProfit(vector<int> &prices) { if (prices.size() == 0) return 0; int profit = 0; int preMin = prices[0]; for (int i = 1; i < prices.size(); i++) { if (prices[i] < pr

Best Time to Buy and Sell Stock Say you have an array for which the ith element is the price of a given stock on day i. If you were only permitted to complete at most one transaction (ie, buy one and sell one share of the stock), design an algorithm