LeetCode: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 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: public int maxPr…

思路: 1. 算法导论讲 divide and conquer 时, 讲到过这个例子. 书中的做法是先让 price 数组减去一个值, 然后求解最大连续子数组的和. 分治算法的复杂度为 o(nlogn) 2. 剑指 offer 来给出最大连续子数组和的动态规划做法, 时间复杂度缩小到 o(n) 3. 此题不必转化为最大连续子数组和问题, 可以直接使用动态规划解法(我不知道如何转化).  假设 dp[i] 表示第 i 天把股票卖出获得的最大收益, 那么可以根据 price[i] 和 price[i…

Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete as many transactions as you like (ie, buy one and sell one share of the stock multiple times) wit…

Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete at most k transactions. Note:You may not engage in multiple transactions at the same time (ie, yo…

Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete at most two transactions. Note:You may not engage in multiple transactions at the same time (ie,…

Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete as many transactions as you like (ie, buy one and sell one share of the stock multiple times). Ho…

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 to find the maximum profit. 这道题相…

Best Time to Buy and Sell Stock II Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete as many transactions as you like (ie, buy one and sell one sha…

原题链接在这里:https://leetcode.com/problems/best-time-to-buy-and-sell-stock-iv/ 题目: Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete at most k transacti…

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…

Your are given an array of integers prices, for which the i-th element is the price of a given stock on day i; and a non-negative integer fee representing a transaction fee. You may complete as many transactions as you like, but you need to pay the t…

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), design…

先看一道leetcode题: Best Time to Buy and Sell Stock II Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete as many transactions as you like (ie, buy one a…

题记:在求最大最小值的类似题目中,递推思想的奇妙之处,在于递推过程也就是比较求值的过程,从而做到一次遍历得到结果. LeetCode 上面的这三道题最能展现递推思想的美丽之处了. 题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 complet…

问题: Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete as many transactions as you like (ie, buy one and sell one share of the stock multiple times)…

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…

将Best Time to Buy and Sell Stock的如下思路用到此题目 思路1:第i天买入,能赚到的最大利润是多少呢?就是i + 1 ~ n天中最大的股价减去第i天的. 思路2:第i天买出,能赚到的最大利润是多少呢?就是第i天的价格减去 0~ i-1天中最小的. 和前两道题比起来的话,这道题最难了,因为限制了交易次数.解决问题的途径我想出来的是:既然最多只能完成两笔交易,而且交易之间没有重叠,那么就divide and conquer.设i从0到n-1,那么针对每一个i,看看在pr…

[称号] Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete at most two transactions. Note: You may not engage in multiple transactions at the same time…

Best Time to Buy and Sell Stock I 你只能一个操作:维修preMin拍摄前最少发生值 代码例如以下: 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] < pre…

1. Best Time to Buy and Sell Stock 2. Best Time to Buy and Sell Stock II 3. Best Time to Buy and Sell Stock III 4. Best Time to Buy and Sell Stock IV 5. Best Time to Buy and Sell Stock with Cooldown 6. Best Time to Buy and Sell Stock with Transaction…

Best Time to Buy and Sell Stock IIIQuestion SolutionSay you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete at most two transactions. Note:You may not en…

Best Time to Buy and Sell Stock IIQuestion SolutionSay you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete as many transactions as you like (ie, buy one…

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…

Question: 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…

Say you have an array for which the i th element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete at most two transactions. Note: You may not engage in multiple transactions at the same time (ie…

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…

这三道题都是同一个背景下的变形:给定一个数组,数组里的值表示当日的股票价格,问你如何通过爱情买卖来发家致富? best time to buy and sell stock i: 最多允许买卖一次 best time to buy and sell stock ii: 不限制买卖次数 best time to buy and sell stock iii:最多允许买卖两次 对于i: 思路就是在第i个位置抛出时,希望在0~i-1个位置上的最低价买入,才能使得第i个位置的收益最大.然后比较所有可以抛…

Best Time to Buy and Sell Stock I 题目: 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 algo…

一.Best Time to Buy and Sell Stock I 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…