leetcode -- Best Time to Buy and Sell Stock III TODO

Say you have an array for which the i^th element is the price of a given stock on day i.

Design an algorithm to find the maximum profit. You may complete at most two transactions.

Note:
You may not engage in multiple transactions at the same time (ie, you must sell the stock before you buy again).

public class Solution {
    public int maxProfit(int[] prices) {
        // Start typing your Java solution below
        // DO NOT write main() function
        if(prices.length == 0){
            return 0;
        }
        int result = Integer.MIN_VALUE;
        int[] profits = new int[prices.length];
        int min = Integer.MAX_VALUE, maxBeforeI = Integer.MIN_VALUE;
        for (int i = 0; i < prices.length; i++) {
            if (prices[i] < min) {
                min = prices[i];
            }
            if (prices[i] - min > maxBeforeI) {
                maxBeforeI = prices[i] - min;
            }
            profits[i] = maxBeforeI;
        }
        int max = Integer.MIN_VALUE;
        for (int i = prices.length - 1; i >= 0; i--) {
            if (prices[i] > max) {
                max = prices[i];
            }

            int profit = max - prices[i];

            if (profit + profits[i] > result) {
                result = profit + profits[i];
            }
        }
        return result;
    }
}

m transactions solution not understand

http://discuss.leetcode.com/questions/287/best-time-to-buy-and-sell-stock-iii