class Solution {
public:
   int maxProfit(vector<int>& prices) {
        int count=0,in=prices[0],out=in;
        for(auto x:prices)
        {
            if(x<out)count+=out-in,in=x,out=in;
            else out=x;
        }
        count+=out-in;
        return count;
    }
};