题目：

题解：

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

        n = len(prices)
        k = min(k, n // 2)
        buy = [0] * (k + 1)
        sell = [0] * (k + 1)

        buy[0], sell[0] = -prices[0], 0
        for i in range(1, k + 1):
            buy[i] = sell[i] = float("-inf")

        for i in range(1, n):
            buy[0] = max(buy[0], sell[0] - prices[i])
            for j in range(1, k + 1):
                buy[j] = max(buy[j], sell[j] - prices[i])
                sell[j] = max(sell[j], buy[j - 1] + prices[i]); 

        return max(sell)