How to find the sum of all the multiples of 3 or 5 below 1000 in Python?

Question

Not sure if I should\'ve posted this on math.stackexchange instead, but it includes more programming so I posted it here.

The question seems really simple, but I\'ve

Answer 1

You are overcomplicating things. You just need a list of numbers that are multiples of 3 or 5 which you can get easily with a list comprehension:

>>> [i for i in range(1000) if i % 3 == 0 or i % 5 == 0]

Then use sum to get the total:

>>> sum([i for i in range(1000) if i % 3 == 0 or i % 5 == 0])
<<< 233168

Or even better use a generator expression instead:

>>> sum(i for i in range(1000) if i % 3 == 0 or i % 5 == 0)

Or even better better (courtesy Exelian):

>>> sum(set(list(range(0, 1000, 3)) + list(range(0, 1000, 5))))