123. 买卖股票的最佳时机 III.go

package main

func main() {

}

func maxProfit4(prices []int) int {
	buy1 := -prices[0]
	sell1 := 0
	buy2 := -prices[0]
	sell2 := 0

	for i := 1; i < len(prices); i++ {
		buy1 = max(buy1, -prices[i])
		sell1 = max(sell1, buy1+prices[i])
		buy2 = max(buy2, sell1-prices[i])
		sell2 = max(sell2, buy2+prices[i])
	}

	return sell2
}

func max(x, y int) int {
	if x > y {
		return x
	}

	return y
}