leetcode -- Best Time to Buy and Sell Stock II

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 (ie, buy one and sell one share of the stock multiple times). However, you may not engage in multiple transactions at the same time (ie, you must sell the stock before you buy again).

[解题思路]

该题不限transaction次数，则将所有的profit都加起来就是maximum profit.而profit出现在每个上升序列中，这里只需要找到所有上升序列即可找到maximum profit。

 

1 public int maxProfit(int[] prices) {
2         int profit = 0;
3         for (int i = 1; i < prices.length; i++) {
4             if (prices[i] - prices[i - 1] > 0)
5                 profit += (prices[i] - prices[i - 1]);
6         }
7         return profit;
8     }

 

证明过程详见：

http://tech-wonderland.net/blog/leetcode-best-time-to-buy-and-sell-stock-ii.html