149. 买卖股票的最佳时机(回顾)

class Solution:
    """
    @param prices: Given an integer array
    @return: Maximum profit
    """
    def maxProfit(self, prices):
        # write your code here
        max_pro = 0 
        buy_price = prices[0]
        for price in prices:
            max_pro = max(max_pro,price-buy_price)
            buy_price = min(buy_price,price)
        return max_pro