# Best time to buy and sell stock II

You are given an integer array prices where prices[i] is the price of a given stock on the ith day.

On each day, you may decide to buy and/or sell the stock. You can only hold **at most one** share of the stock at any time. However, you can buy it then immediately sell it on the **same day**.

Find and return *the ***maximum*** profit you can achieve*.

```
class Solution:
def maxProfit(self, prices: List[int]) -> int:
price_gain = []
for idx in range( len(prices)-1 ):
if prices[idx] < prices[idx+1]:
price_gain.append( prices[idx+1]- prices[idx])
return sum( price_gain )
```

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