Aristocracy

n = int(input())
names = {}
for _ in range(n):
    s, nb = input().split()
    nb = int(nb)
    if s not in names:
        names[s] = set()
    names[s].add(nb)

M = int(1e9) + 7
# M = 3
fact = [0] * (n+1)
fact[0] = 1
for i in range(1, n+1):
    fact[i] = (fact[i-1] * i) % M

ans = fact[n]
div = 1
for key in names:
    div = (div * fact[len(names[key])]) % M

x = 1
y = 0
x1 = 0
y1 = 1
a1 = div 
b1 = M
while b1 > 0:
    q = a1 // b1
    x, x1 = x1, x - q * x1
    y, y1 = y1, y - q * y1
    a1, b1 = b1, a1 - q * b1

# ret a1

print(ans * x % M)

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED

Test 16

Verdict: ACCEPTED

Test 17

Verdict: ACCEPTED