Best Time to Buy and Sell Stock II( p-122)

# two pointer approach with tc O(n) and sc is O(1)

class Solution:
    def maxProfit(self, prices: List[int]) -> int:        
       l=0
       r=1
       csum=0
       pro=0
       while(r<len(prices)):
        if(prices[l]<prices[r]):
            csum+=prices[r]-prices[l]
        
        l=r
        r=l+1
        pro=max(pro,csum)
        
       return pro