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).

 本题采用的贪心算法，只要今天的价格比前天高，就卖出即可

class Solution {public:    int maxProfit(vector<int> &prices) {        int total = 0;        for (int i=1; i< prices.size(); i++) {            if (prices[i]>prices[i-1])                 total += prices[i]-prices[i-1];        }        return total;    }};