123.买卖股票的最佳时机-iii.py

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# @lc app=LeetCode.cn id=123 lang=python3
#
# [123] 买卖股票的最佳时机 III
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# @lc code=start
class Solution:
    def maxProfit(self, prices: List[int]) -> int:
        dp_i10 = 0
        dp_i20 = 0
        dp_i11 = -max(prices)-1
        dp_i21 = -max(prices)-1
        for price in prices:
            dp_i20 = max(dp_i20, dp_i21 + price)
            dp_i21 = max(dp_i21, dp_i10 - price)
            dp_i10 = max(dp_i10, dp_i11 + price)
            dp_i11 = max(dp_i11, -price)
        return dp_i20
# @lc code=end