LeetCode OJ--Best Time to Buy and Sell Stock II

http://oj.leetcode.com/problems/best-time-to-buy-and-sell-stock-ii/

第二问，是说可以进行无数次买卖。

贪心法

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

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

int main()
{
    Solution myS;
    vector<int> price;
    price.push_back(1);
    price.push_back(2);
    price.push_back(8);
    price.push_back(1);
    price.push_back(4);
    price.push_back(3);
    price.push_back(-1);
    myS.maxProfit(price);
    return 0;
}