1 public class Solution {
 2     public int maxProfit(int[] prices) {
 3         if (prices.length <= 1) return 0;
 4 
 5         boolean hasStock = false;
 6         int sumProfit = 0;
 7         int min = 0;
 8         
 9         for(int i = 0; i < prices.length - 1; i++) {
10             if (hasStock) {
11                 if (prices[i] > prices[i + 1]) {
12                     sumProfit += prices[i] - min;
13                     hasStock = false;
14                 }
15             } else {
16                 if (prices[i] < prices[i + 1]) {
17                     min = prices[i];
18                     hasStock = true;
19                 }
20             }
21         }
22         if (hasStock) sumProfit += prices[prices.length - 1] - min;
23         return sumProfit;
24     }
25 }