#pragma GCC optimize("O2") #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define int ll #define INT128_MAX (__int128)(((unsigned __int128) 1 << ((sizeof(__int128) * __CHAR_BIT__) - 1)) - 1) #define INT128_MIN (-INT128_MAX - 1) #define clock chrono::steady_clock::now().time_since_epoch().count() #ifdef DEBUG #define dbg(x) cout << (#x) << " = " << x << '\n' #else #define dbg(x) #endif namespace R = std::ranges; namespace V = std::views; using namespace std; using ll = long long; using ull = unsigned long long; using ldb = long double; using pii = pair; using pll = pair; //#define double ldb template ostream& operator<<(ostream& os, const pair pr) { return os << pr.first << ' ' << pr.second; } template ostream& operator<<(ostream& os, const array &arr) { for(const T &X : arr) os << X << ' '; return os; } template ostream& operator<<(ostream& os, const vector &vec) { for(const T &X : vec) os << X << ' '; return os; } template ostream& operator<<(ostream& os, const set &s) { for(const T &x : s) os << x << ' '; return os; } //note: inversion only works when MOD is a prime struct mint { static long long MOD; long long _val; mint(long long init = 0) { _val = init % MOD; (*this).norm(); } mint POW(long long index) { if (index == 0) return mint(1ll); mint base = *this; mint res = (base == 0ll ? 0ll : 1ll); while(index) { if (index & 1) res *= base; base *= base, index >>= 1; } return res; } mint inv() { return (*this).POW(MOD - 2); } mint& norm() { if (_val >= MOD) _val -= MOD; if (_val < 0) _val += MOD; return *this; } mint& operator+=(mint b) { _val += b._val; return (*this).norm(); } mint& operator-=(mint b) { _val -= b._val; return (*this).norm(); } mint& operator*=(mint b) { _val = (_val * b._val) % MOD; return *this; } mint& operator/=(mint b) { _val = (_val * b.inv()._val) % MOD; return *this; } mint& operator++() { _val += 1; return (*this).norm(); } mint& operator--() { _val -= 1; return (*this).norm(); } mint operator++(signed) { mint tmp = *this; ++(*this); return tmp; } mint operator--(signed) { mint tmp = *this; --(*this); return tmp; } mint operator-() { return mint(-_val); } bool operator==(mint b) { return _val == b._val; } bool operator!=(mint b) { return _val != b._val; } friend mint operator+(mint a, mint b) { return a += b; } friend mint operator-(mint a, mint b) { return a -= b; } friend mint operator*(mint a, mint b) { return a *= b; } friend mint operator/(mint a, mint b) { return a /= b; } friend ostream& operator<<(ostream& os, const mint& b) { return os << b._val; } friend istream& operator>>(istream& is, mint& b) { long long val; is >> val; b = mint(val); return is; } }; ll mint::MOD = 2; signed main() { ios::sync_with_stdio(false), cin.tie(NULL); int n; cin >> n >> mint::MOD; vector> dp(2 * n); dp[1] = {1, 1, 1}; for(int i = 1; i < 2 * n - 3; i++) { for(int j : {0, 1, 2}) { dp[i + 1][j] += dp[i][0]; dp[i + 2][j] += dp[i][1] * (i + 1); dp[i + 3][j] += dp[i][2] * (i + 1) * (i + 2); } for(int j : {1, 2}) { dp[i + 1][j] += dp[i][1]; dp[i + 2][j] += dp[i][2] * (i + 1); } dp[i + 1][2] += dp[i][2]; } mint ans = 1; for(int i = 2; i <= (2 * n - 1); i++) ans *= i; for(int i = 1; i <= 2 * n - 3; i += 2) ans *= dp[i][2]; cout << ans << '\n'; return 0; }