Python/maths/combinations.py

20 lines
319 B
Python
Raw Normal View History

from math import factorial
def combinations(n, k):
"""
>>> combinations(10,5)
252
>>> combinations(6,3)
20
>>> combinations(20,5)
15504
"""
return int(factorial(n) / ((factorial(k)) * (factorial(n - k))))
if __name__ == "__main__":
from doctest import testmod
testmod()