#include <iostream>

#include <vector>

using namespace std;

class Solution {

public:

    int maxProfit(vector<int> &prices) {

        if(prices.empty())

            return NULL;

        if(prices.size()==)

            return ;

        int ans = ;

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

        {

            if(prices[i]>prices[i-])

                ans = ans - prices[i-] +prices[i];

        }

        return ans;

    }

};

int main()

{

    Solution myS;

    vector<int> price;

    price.push_back();

    price.push_back();

    price.push_back();

    price.push_back();

    price.push_back();

    price.push_back();

    price.push_back(-);

    myS.maxProfit(price);

    return ;

}