# [Best Time to Buy and Sell Stock II][title] ## Description 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 as many transactions as you like (i.e., buy one and sell one share of the stock multiple times). **Note:** You may not engage in multiple transactions at the same time (i.e., you must sell the stock before you buy again). **Example 1:** ``` Input: [7,1,5,3,6,4] Output: 7 Explanation: Buy on day 2 (price = 1) and sell on day 3 (price = 5), profit = 5-1 = 4. Then buy on day 4 (price = 3) and sell on day 5 (price = 6), profit = 6-3 = 3. ``` **Example 2:** ``` Input: [1,2,3,4,5] Output: 4 Explanation: Buy on day 1 (price = 1) and sell on day 5 (price = 5), profit = 5-1 = 4. Note that you cannot buy on day 1, buy on day 2 and sell them later, as you are engaging multiple transactions at the same time. You must sell before buying again. ``` **Example 3:** ``` Input: [7,6,4,3,1] Output: 0 Explanation: In this case, no transaction is done, i.e. max profit = 0. ``` **Tags:** Array, Greedy ## 思路 题意是给出一个数组代表每天的股票金额,在每天只能买或卖的情况下求出收益最高值,这...,这也太简单了吧,把所有相邻递增的值都加起来即可。 ```java class Solution { public int maxProfit(int[] prices) { int max = 0; for (int i = 1; i < prices.length; ++i) { if (prices[i] > prices[i - 1]) max += prices[i] - prices[i - 1]; } return max; } } ``` ## 结语 如果你同我一样热爱数据结构、算法、LeetCode,可以关注我 GitHub 上的 LeetCode 题解:[awesome-java-leetcode][ajl] [title]: https://leetcode.com/problems/best-time-to-buy-and-sell-stock-ii [ajl]: https://github.com/Blankj/awesome-java-leetcode