leetcode：714. The best time to buy and sell stocks includes handling fee [DP dual status]

analysis

dp[i][0] It means the first one i No stock in positions max profits ,dp[i][1] It means the first one i There are stocks in positions max profits
The first 0 One of the dp Namely [0, -prices[0]]
then dp[i][0] yes max（ There was no stock continuation before , There were shares before but they were sold ）
then dp[i][1] yes max（ There was a continuation of the stock , I didn't have any stocks before, but I bought ）

ac code

class Solution:
    def maxProfit(self, prices: List[int], fee: int) -> int:
        # dp[i][0]:  The first i There is no stock's maximum profit 
        # dp[i][1]:  The first i Tianyou stock's maximum profit 
        #  Two states 
        n = len(prices)
        dp = [[0, -prices[0]]] + [[0, 0] for _ in range(n - 1)]

        for i in range(1, n):
            dp[i][0] = max(dp[i - 1][0], dp[i - 1][1] + prices[i] - fee)
            dp[i][1] = max(dp[i - 1][1], dp[i - 1][0] - prices[i])
        
        return dp[-1][0]

summary

dp Two states
Interact with each other
Another dp Multistate , All right