1 public class Solution { 2     public int maxProfit(int[] prices) { 3         if (prices.length <= 1) return 0; 4          5         int profit = 0; 6         int buyPrices=prices[0]; 7          8         for (int i=1; i<prices.length; i++) { 9             profit = Math.max(profit, prices[i]-buyPrices);10             if (buyPrices > prices[i]) buyPrices = prices[i];11         }12         return profit;13     }14 }