标签：nbsp div sel max complete time sam i++ let
Say you have an array for which the ith 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).
之前题的扩展，要求是只能买卖两次，然后求出最大利润。
利用动态规划，从前向后和从后向前各求一次，然后求出结果。
public class Solution { public int maxProfit(int[] prices) { int len = prices.length; if( len < 2 ) return 0; int[] preProfit = new int[len]; int[] maxProfit = new int[len]; int cur = prices[0]; preProfit[0] = 0; for( int i = 1;i<len;i++){ cur = Math.min(cur,prices[i]); preProfit[i] = Math.max(preProfit[i-1],prices[i] - cur); } cur = prices[len-1]; maxProfit[len-1] = 0; for( int i = len-2;i>=0;i--){ cur = Math.max(cur,prices[i]); maxProfit[i] = Math.max(maxProfit[i+1],cur - prices[i]); } int result = 0; for( int i = 0;i<len;i++){ result = Math.max(preProfit[i]+maxProfit[i],result); } return result; } }
leetcode 123. Best Time to Buy and Sell Stock III ----- java
标签：nbsp div sel max complete time sam i++ let
原文地址：http://www.cnblogs.com/xiaoba1203/p/6032861.html
