/* -*- coding: utf-8 -*- * * 109.cc: No.109 N! mod M - yukicoder */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; /* constant */ const int MAX_N = 1000000000; const int MAX_P = 32000; /* typedef */ typedef long long ll; typedef vector vi; /* global variables */ bool primes[MAX_P + 1]; vi pnums; /* subroutines */ void gen_primes(int maxp, vi &pnums) { memset(primes, true, sizeof(primes)); primes[0] = primes[1] = false; int p; for (p = 2; p * p <= maxp; p++) if (primes[p]) { pnums.push_back(p); for (int q = p * p; q <= maxp; q += p) primes[q] = false; } for (; p <= maxp; p++) if (primes[p]) pnums.push_back(p); } bool is_prime(int m) { if (m <= MAX_P) return primes[m]; for (vi::iterator vit = pnums.begin(); vit != pnums.end() && *vit * *vit <= m; vit++) if (m % *vit == 0) return false; return true; } ll powmod(ll a, int n, int m) { // a^n % m ll pm = 1; while (n > 0) { if (n & 1) pm = (pm * a) % m; a = (a * a) % m; n >>= 1; } return pm; } /* main */ int main() { gen_primes(MAX_P, pnums); int pn = pnums.size(); //printf("pn=%d, maxp=%d\n", pn, pnums.back()); int tn; cin >> tn; while (tn--) { int n, m; cin >> n >> m; int ans = 0; if (n < m) { if (m <= 200000) { ll f = 1; for (int i = 1; i <= n; i++) f = (f * i) % m; ans = f; } else if (is_prime(m)) { ll f = 1; for (int i = n + 1; i < m; i++) f = (f * i) % m; ans = (ll)(m - 1) * powmod(f, m - 2, m) % m; } } printf("%d\n", ans); } return 0; }