https://leetcode-cn.com/problems/best-time-to-buy-and-sell-stock-with-transaction-fee/
买入卖出收取一笔手续费.
每花一笔手续费, balance -= fee.
Golang
const (
EmptyPosition = iota
FullPosition
)
func maxProfit(prices []int, fee int) int {
dp := make([][]int, len(prices)+1) // [第几天][仓位] => balance
for i := 0; i < len(dp); i++ {
dp[i] = []int{math.MinInt32, math.MinInt32}
}
dp[0][EmptyPosition] = 0
dp[0][FullPosition] = -prices[0]
for day := 1; day <= len(prices); day++ {
todayPrice := prices[day-1]
dp[day][FullPosition] = max(
dp[day-1][FullPosition],
dp[day-1][EmptyPosition]-todayPrice, // buy
)
dp[day][EmptyPosition] = max(
dp[day-1][EmptyPosition],
dp[day-1][FullPosition]+todayPrice-fee, // sell
)
}
return dp[len(prices)][EmptyPosition]
}
func max(a, b int) int {
if a > b {
return a
}
return b
}