121.Best Time to Buy and Sell Stock

Greedy Approach: At each step, choose the best immediate option without worrying about future steps.(O(n))

class Solution {
public:
    int maxProfit(vector<int>& prices) {
        int min=INT_MAX;
        int profit=0;
      for(int i=0;i<prices.size();i++){
          if (prices[i]<min){
            min=prices[i];
           }
        profit=max(profit,prices[i]-min);
      }
      return profit;
    }

};