import sys V = sys.version_info _39 = False _310 = False _311 = False if V.major == 3: _39 = V.minor >= 9 _310 = V.minor >= 10 _311 = V.minor >= 11 if _39: li = list tup = tuple dic = dict st = set ty = type else: from typing import ( List, Tuple, Type, Dict, Set, ) li = List tup = Tuple dic = Dict st = Set ty = Type from sys import stdin read = stdin.buffer.read rl = stdin.buffer.readline rb = lambda: rl().split() rls = stdin.buffer.readlines from typing import ( TypeVar, Sequence as Seq, Iterable as Iter, Protocol as Proto, Generic as Gen, ) from typing import Callable as Fn from typing import Iterable def prints( a: Iterable[object], sep: str = "\n", ) -> None: print(sep.join(map(str, a))) # import numpy as np def egcd( a: int, b: int, ) -> tup[int, int, int]: if not b: if a < 0: return -a, -1, 0 return a, 1, 0 q, r = divmod(a, b) g, s, t = egcd(b, r) return g, t, s - q * t def crt_mod( m: Seq[int], r: Seq[int], mod: int, ) -> int: l = len(m) assert len(r) == l m = list(m) + [mod] p = [1] * (l + 1) x = [0] * (l + 1) for i, (n, b) in enumerate(zip(m, r)): assert n > 0 g, ip, _ = egcd(p[i], n) q, a = divmod(b - x[i], g) if a: return -1 n //= g t = q % n * ip for j in range(i + 1, l + 1): x[j] += t * p[j] x[j] %= m[j] p[j] = p[j] * n % m[j] return x[-1] def factorize(n: int) -> li[tup[int, int]]: f = [] for i in range(2, n): if i * i > n: break if n % i: continue c = 0 while n % i == 0: n //= i c += 1 f.append((i, c)) if n > 1: f.append((n, 1)) return f def factorize_lcm( a: Iter[int], ) -> dic[int, int]: f = dict() for x in a: for p, e in factorize(x): c = f.get(p, 0) f[p] = max(c, e) return f def lcm_mod(m: int, a: Iter[int]) -> int: l = 1 for p, e in factorize_lcm(a).items(): l = l * pow(p, e, m) % m return l def solve() -> None: n = int(rl()) rm = [map(int, rb()) for _ in range(n)] r, m = list(zip(*rm)) mod = 10**9 + 7 if max(r) == 0: print(lcm_mod(mod, m)) else: print(crt_mod(m, r, mod)) def main() -> None: t = 1 # t = int(rl()) for _ in range(t): solve() main()