Best Time to Buy and Sell Stock III

class Solution {public:    int maxProfit(vector<int> &prices) {        if(prices.size()<=1)            return 0;        int left[prices.size()];        int minp=prices[0];        left[0]=0;        for(int i=1;i<prices.size();i++)        {            minp=min(minp,prices[i]);            left[i]=max(left[i-1],prices[i]-minp);        }        int maxp=prices[prices.size()-1];        int maxprofit=0;        for(int i=prices.size()-2;i>=0;i--)        {            maxp=max(maxp,prices[i]);            maxprofit=max(maxprofit,left[i]+maxp-prices[i]);        }        return maxprofit;    }};