class Solution(object):
    def maxProfit(self, prices):
        """
        :type prices: List[int]
        :rtype: int
        """
        if len(prices) == 0 or len(prices) == 1:
            return 0
        
        minP = prices[0]
        result = 0
        
        for price in prices:
            # Maintain the maximum profit at each price
            result = max(result, price - minP)
            
            # Maintain the minimum price seen so far
            minP = min(minP, price)
                
        if result < 0:
            return 0
        
        return result

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