[LeetCode] 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 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).

题意：买卖股票的第二题。与1的变化在于可以买卖任意次数，但必须保证买卖一次后才能进行第二次。

分析：实际上是求波浪线的所有上升段的长度和。

 

class Solution {
    public:
        int maxProfit(vector<int> &prices) 
        {   
            int res = 0;

            if(prices.size() == 0)
                return res;

            for(int i = 1; i < prices.size(); i++)
            {   
                if(prices[i] > prices[i-1])
                    res += ( prices[i] - prices[i-1]);
            }   

            return res;
        }   

};