# Leetcode 122. The best time to buy and sell stocks II Python implementation

Time：2021-2-6
• Title Requirements:

• Thinking:

• Buy and sell stocks every day, sell the one day before, and buy the one day after
• Maintain a res to save the total profit
• If the stock price of the day is higher than that of the previous day, that is, there is a profit, add the profit to res. if there is no profit, add res to 0
• Core code:
``````res = 0
for i in range(1,len(prices)):
res += max(0, prices[i] - prices[i - 1])
return res``````
• Full code:
``````class Solution:
def maxProfit(self, prices: List[int]) -> int:
res = 0
for i in range(1,len(prices)):
res += max(0, prices[i] - prices[i - 1])
return res``````

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