def nested_sum(L):
return sum( nested_sum(x) if isinstance(x, list) else x for x in L )
This was a solution given by Eugenie in the following post: sum of nested list in Python
I just was trying to recreate it without using comprehension list, but I'm not able to get it. How could I do it?
The code uses a generator expression, not a list comprehension.
Use a loop and += adding up the results:
def nested_sum(L):
total = 0
for x in L:
total += nested_sum(x) if isinstance(x, list) else x
return total
or, if you want the conditional expression expanded into an if statement as well:
def nested_sum(L):
total = 0
for x in L:
if isinstance(x, list):
total += nested_sum(x)
else:
total += x
return total
