74. maximum profit on shares

subject

Suppose you store the price of a stock in an array in chronological order , What's the maximum profit you can get from buying and selling this stock at one time ？

Input : [7,1,5,3,6,4]
Output : 5
explain : In the 2 God （ Stock price = 1） Buy when , In the 5 God （ Stock price = 6） Sell when , Maximum profit = 6-1 = 5 .
Note that profit cannot be 7-1 = 6, Because the selling price needs to be higher than the buying price .

Ideas

Greedy Algorithm ： Maintain a buying minimum , And a maximum profit at the time of sale .

Code

class Solution:
    def maxProfit(self, prices: List[int]) -> int:
        if not prices:
            return 0
        Min=prices[0]
        Max=0
        for i in range(0, len(prices)):
            Min=min(Min, prices[i])
            Max=max(Max, prices[i]-Min)
        return Max