mirror of
https://github.com/TheAlgorithms/Python.git
synced 2024-11-27 23:11:09 +00:00
927e14e7f2
* mv str statement into docstr * rename var to avoid redefining builtin * clean up module docstr
34 lines
790 B
Python
34 lines
790 B
Python
"""
|
|
Problem Statement:
|
|
If we list all the natural numbers below 10 that are multiples of 3 or 5,
|
|
we get 3, 5, 6 and 9. The sum of these multiples is 23.
|
|
Find the sum of all the multiples of 3 or 5 below N.
|
|
"""
|
|
|
|
|
|
def solution(n: int = 1000) -> int:
|
|
"""Returns the sum of all the multiples of 3 or 5 below n.
|
|
|
|
>>> solution(3)
|
|
0
|
|
>>> solution(4)
|
|
3
|
|
>>> solution(10)
|
|
23
|
|
>>> solution(600)
|
|
83700
|
|
"""
|
|
|
|
total = 0
|
|
terms = (n - 1) // 3
|
|
total += ((terms) * (6 + (terms - 1) * 3)) // 2 # total of an A.P.
|
|
terms = (n - 1) // 5
|
|
total += ((terms) * (10 + (terms - 1) * 5)) // 2
|
|
terms = (n - 1) // 15
|
|
total -= ((terms) * (30 + (terms - 1) * 15)) // 2
|
|
return total
|
|
|
|
|
|
if __name__ == "__main__":
|
|
print(solution(int(input().strip())))
|