[백준] 다리 놓기

 

문제

t = int(input())

def factorial(n):
    if n == 0:
        return 1
    return n * factorial(n - 1)

def comb(n, m):
    return factorial(n) // (factorial(m) * factorial(n - m))

for i in range(t):
    n, m = map(int, input().split())
    print(comb(m, n))