题目：

题解：

func maxProfit(prices []int) int {if len(prices) == 0 {return 0}n := len(prices)f0, f1, f2 := -prices[0], 0, 0for i := 1; i < n; i++ {newf0 := max(f0, f2 - prices[i])newf1 := f0 + prices[i]newf2 := max(f1, f2)f0, f1, f2 = newf0, newf1, newf2}return max(f1, f2)
}func max(x, y int) int {if x > y {return x}return y
}