Best Time to Buy and Sell Stock.cpp

    int maxProfit(vector<int>& p) {
        int ans=0, min=p[0];
        for(int i=1;i<p.size();i++){
            if(p[i]<min) min=p[i];
            else{
                ans = max(ans, p[i]-min);
            }
        }
        return ans;
    }