2023-08-08 20:36:48 +0000 UTC

class Solution:
    def maxProfit(self, prices: List[int]) -> int:
        if not prices:
            return 0

        # initialize variables for first buy, first sell, second buy, and second sell
        buy1, buy2 = float('inf'), float('inf')
        sell1, sell2 = 0, 0

        # iterate over prices to update buy and sell values
        for price in prices:
            # update first buy and sell values
            buy1 = min(buy1, price)
            sell1 = max(sell1, price - buy1)
            # update second buy and sell values
            buy2 = min(buy2, price - sell1)
            sell2 = max(sell2, price - buy2)

        return sell2