123. Best Time to Buy and Sell Stock III

Description

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 (i.e., you must sell the stock before you buy again).

Example 1:

Input: [3,3,5,0,0,3,1,4]
Output: 6
Explanation: Buy on day 4 (price = 0) and sell on day 6 (price = 3), profit = 3-0 = 3.
             Then buy on day 7 (price = 1) and sell on day 8 (price = 4), profit = 4-1 = 3.

Example 2:

Input: [1,2,3,4,5]
Output: 4
Explanation: Buy on day 1 (price = 1) and sell on day 5 (price = 5), profit = 5-1 = 4.
             Note that you cannot buy on day 1, buy on day 2 and sell them later, as you are
             engaging multiple transactions at the same time. You must sell before buying again.

Example 2:

Input: [7,6,4,3,1]
Output: 0
Explanation: In this case, no transaction is done, i.e. max profit = 0.

Tags: Math, String

题意

买卖股票,持有一股,买卖2此

题解

思路1

func maxProfit(prices []int) int {
    t1_b, t1_s, t2_b, t2_s := math.MinInt32, 0, math.MinInt32, 0

    for _, v := range prices {
        t1_b = max(t1_b, 0-v)
        t1_s = max(t1_s, t1_b+v)
        t2_b = max(t2_b, t1_s-v)
        t2_s = max(t2_s, t2_b+v)
    }
    return t2_s
}
func max(a, b int) int {
    if a < b {
        return b
    }
    return a
}

结语

如果你同我一样热爱数据结构、算法、LeetCode,可以关注我 GitHub 上的 LeetCode 题解:awesome-golang-leetcode

results matching ""

    No results matching ""