122. 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).
Analysis:
将其想像为连续函数，低买高卖，计算出每个上升区间累加的和即可。
参考：http://blog.csdn.net/fightforyourdream/article/details/14449133
Source Code（C++）:

#include <iostream>
#include <vector>
using namespace std;

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

int main() {
    vector<int> v;
    v.push_back(1);
    Solution sol;
    cout << sol.maxProfit(v);
    return 0;
}