1. 122

best-time-to-buy-and-sell-stock-ii

--

2. 算法

http://www.cnblogs.com/grandyang/p/4280803.html

此题和上面一题的不同之处在于不限制交易次数。也是一次遍历即可，只要可以赚就做交易。

3. 代码

class Solution {

public:

    int maxProfit(vector<int> &prices) {

        if (prices.empty()) return 0;

        int res = 0;

        for (int i = 1; i < prices.size(); ++i) {

            if (prices[i] - prices[i - 1] > 0) {

                res += prices[i] - prices[i - 1];

            }

        }

        return res;

    }

};