結果
問題 | No.117 組み合わせの数 |
ユーザー | 👑 emthrm |
提出日時 | 2019-10-25 15:37:23 |
言語 | C++17 (gcc 12.3.0 + boost 1.83.0) |
結果 |
RE
|
実行時間 | - |
コード長 | 4,736 bytes |
コンパイル時間 | 825 ms |
コンパイル使用メモリ | 88,336 KB |
実行使用メモリ | 32,452 KB |
最終ジャッジ日時 | 2024-07-19 21:31:36 |
合計ジャッジ時間 | 2,888 ms |
ジャッジサーバーID (参考情報) |
judge3 / judge2 |
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ソースコード
#include <algorithm> // #include <cassert> #include <iostream> #include <iomanip> #include <utility> #include <vector> using namespace std; #define FOR(i,m,n) for(int i=(m);i<(n);++i) const int MOD = 1000000007; // 998244353; struct IOSetup { IOSetup() { cin.tie(nullptr); ios_base::sync_with_stdio(false); cout << fixed << setprecision(20); cerr << fixed << setprecision(10); } } iosetup; /*-------------------------------------------------*/ long long mod_inv(long long a, int mod = MOD) { a %= mod; if (__gcd(a, static_cast<long long>(mod)) != 1) return -1; long long b = mod, x = 1, y = 0; while (b > 0) { long long tmp = a / b; a -= tmp * b; swap(a, b); x -= tmp * y; swap(x, y); } x %= mod; if (x < 0) x += mod; return x; } struct nCk { int val, mod; vector<long long> fact, fact_inv; nCk(int val = 10000000, int mod = MOD) : val(val), mod(mod), fact(val + 1), fact_inv(val + 1) { fact[0] = 1; FOR(i, 1, val + 1) fact[i] = fact[i - 1] * i % mod; fact_inv[val] = mod_inv(fact[val], mod); for (int i = val; i > 0; --i) fact_inv[i - 1] = fact_inv[i] * i % mod; } long long query(int n, int k) { if (n < 0 || n < k || k < 0) return 0; // assert(n <= val && k <= val); return fact[n] * fact_inv[k] % mod * fact_inv[n - k] % mod; } }; int mod = MOD; struct ModInt { unsigned val; ModInt(): val(0) {} ModInt(long long x) : val(x >= 0 ? x % mod : x % mod + mod) {} ModInt pow(long long exponent) { ModInt tmp = *this, res = 1; while (exponent > 0) { if (exponent & 1) res *= tmp; tmp *= tmp; exponent >>= 1; } return res; } ModInt &operator+=(const ModInt &rhs) { if((val += rhs.val) >= mod) val -= mod; return *this; } ModInt &operator-=(const ModInt &rhs) { if((val += mod - rhs.val) >= mod) val -= mod; return *this; } ModInt &operator*=(const ModInt &rhs) { val = static_cast<unsigned long long>(val) * rhs.val % mod; return *this; } ModInt &operator/=(const ModInt &rhs) { return *this *= rhs.inv(); } bool operator==(const ModInt &rhs) const { return val == rhs.val; } bool operator!=(const ModInt &rhs) const { return val != rhs.val; } bool operator<(const ModInt &rhs) const { return val < rhs.val; } bool operator<=(const ModInt &rhs) const { return val <= rhs.val; } bool operator>(const ModInt &rhs) const { return val > rhs.val; } bool operator>=(const ModInt &rhs) const { return val >= rhs.val; } ModInt operator-() const { return ModInt(val ? mod - val : 0); } ModInt operator+(const ModInt &rhs) const { return ModInt(*this) += rhs; } ModInt operator-(const ModInt &rhs) const { return ModInt(*this) -= rhs; } ModInt operator*(const ModInt &rhs) const { return ModInt(*this) *= rhs; } ModInt operator/(const ModInt &rhs) const { return ModInt(*this) /= rhs; } friend ostream &operator<<(ostream &os, const ModInt &rhs) { return os << rhs.val; } friend istream &operator>>(istream &is, ModInt &rhs) { long long x; is >> x; rhs = ModInt(x); return is; } private: ModInt inv() const { // if (__gcd(val, mod) != 1) assert(false); unsigned a = val, b = mod; int x = 1, y = 0; while (b) { unsigned tmp = a / b; swap(a -= tmp * b, b); swap(x -= tmp * y, y); } return ModInt(x); } }; int abs(const ModInt &x) { return x.val; } struct Combinatorics { int val; vector<ModInt> fact, fact_inv, inv; Combinatorics(int val = 10000000) : val(val), fact(val + 1), fact_inv(val + 1), inv(val + 1) { fact[0] = 1; FOR(i, 1, val + 1) fact[i] = fact[i - 1] * i; fact_inv[val] = ModInt(1) / fact[val]; for (int i = val; i > 0; --i) fact_inv[i - 1] = fact_inv[i] * i; FOR(i, 1, val + 1) inv[i] = fact[i - 1] * fact_inv[i]; } ModInt nCk(int n, int k) { if (n < 0 || n < k || k < 0) return ModInt(0); // assert(n <= val && k <= val); return fact[n] * fact_inv[k] * fact_inv[n - k]; } ModInt nPk(int n, int k) { if (n < 0 || n < k || k < 0) return ModInt(0); // assert(n <= val); return fact[n] * fact_inv[n - k]; } ModInt nHk(int n, int k) { if (n < 0 || k < 0) return ModInt(0); return (k == 0 ? ModInt(1) : nCk(n + k - 1, k)); } }; int main() { Combinatorics com(1000000); nCk nck(1000000); int t; cin >> t; while (t--) { string s; cin >> s; string n = ""; int idx = 2; for (; ; ++idx) { char c = s[idx]; if (c == ',') break; n += c; } string k = s.substr(idx + 1); if (s[0] == 'C') { cout << nck.query(stoi(n), stoi(k)); } else if (s[0] == 'P') { cout << com.nPk(stoi(n), stoi(k)); } else { cout << com.nHk(stoi(n), stoi(k)); } cout << '\n'; } return 0; }