Codeup 1288 - nCr (Tiny)

http://codeup.kr/problem.php?id=1288

 

Codeup 1288 - nCr (Tiny)

 

x
n, r = map(int, input().split())
def factorial(n):
    if n == 1 or n == 0:
        return 1
    else:
        return n * factorial(n-1)
print(int(factorial(n) / (factorial(r) * factorial(n-r))))