結果
問題 | No.117 組み合わせの数 |
ユーザー | T1610 |
提出日時 | 2020-08-29 15:49:58 |
言語 | C++17 (gcc 12.3.0 + boost 1.83.0) |
結果 |
RE
|
実行時間 | - |
コード長 | 3,446 bytes |
コンパイル時間 | 2,356 ms |
コンパイル使用メモリ | 211,800 KB |
実行使用メモリ | 20,152 KB |
最終ジャッジ日時 | 2024-11-14 14:10:25 |
合計ジャッジ時間 | 4,101 ms |
ジャッジサーバーID (参考情報) |
judge5 / judge2 |
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ソースコード
#include <bits/stdc++.h> using namespace std; #define rep(i,n) REP(i,0,n) #define REP(i,s,e) for(int i=(s); i<(int)(e); i++) #define repr(i, n) REPR(i, n, 0) #define REPR(i, s, e) for(int i=(int)(s-1); i>=(int)(e); i--) #define all(r) r.begin(),r.end() #define rall(r) r.rbegin(),r.rend() typedef long long ll; typedef vector<int> vi; typedef vector<ll> vl; const ll INF = 1e18; const ll MOD = 1e9 + 7; template<typename T> T chmax(T& a, const T& b){return a = (a > b ? a : b);} template<typename T> T chmin(T& a, const T& b){return a = (a < b ? a : b);} template <typename T, typename U> T pow_fast(T x, U n) { T ret = (T)1; while(n) { if(n & (U)1) ret *= x; x *= x; n >>= 1; } return ret; } template <typename ModType, ModType MOD> struct ModInt { ModType val; ModInt() : val(0) {} ModInt(ModType x) : val(x % MOD) { if(val < 0) val += MOD; }; operator ModType() const { return val; } ModInt &operator+=(const ModInt &m) { val += m.val; if(val >= MOD) val -= MOD; return *this; } ModInt &operator-=(const ModInt &m) { val -= m.val; if(val < 0) val += MOD; return *this; } ModInt &operator*=(const ModInt &m) { (val *= m.val) %= MOD; return *this; } ModInt &operator/=(const ModInt &m) { *this *= m.inverse(); return *this; } ModInt operator+(const ModInt &m) const { return ModInt(*this) += m; } ModInt operator-(const ModInt &m) const { return ModInt(*this) -= m; } ModInt operator*(const ModInt &m) const { return ModInt(*this) *= m; } ModInt operator/(const ModInt &m) const { return ModInt(*this) /= m; } ModInt inverse() const { return pow_fast(*this, MOD - 2); } ModInt pow(ModType n) const {return pow_fast(*this, n); } friend std::ostream &operator<<(std::ostream &os, const ModInt &rhs) { os << rhs.val; return os; } friend std::istream &operator>>(std::istream &is, ModInt &rhs) { ModType value; is >> value; rhs = ModInt(value); return is; } }; template <class mint> struct Comb { vector<mint> fact; vector<mint> ifact; const int N; Comb(int n) : N(n + 1), fact(n + 1), ifact(n + 1) { makeFact(); } void makeFact() { fact[0] = ifact[0] = 1LL; for(int i = 1; i < N; i++) { fact[i] = fact[i - 1] * (mint)i; ifact[i] = fact[i].inverse(); } } mint operator()(int n, int r) { if(n < 0 || r < 0 || r > n) return 0; if(r > n / 2) r = n - r; return fact[n] * ifact[n - r] * ifact[r]; } }; using mint = ModInt<ll, MOD>; vector<string> split(const string& s, char c = ' ') { vector<string> ret; stringstream ss(s); string t; while (getline(ss, t, c)) { ret.emplace_back(t); } return ret; } int main(){ cin.tie(0); ios::sync_with_stdio(false); int t; cin >> t; Comb<mint> cmb(1e6+10); rep(i, t) { string s; cin >> s; char c = s[0]; s = s.substr(2); s.pop_back(); auto v = split(s, ','); int a = stoi(v[0].c_str()); int b = stoi(v[1].c_str()); mint ans; if(c == 'C') ans = cmb(a, b); else if(c == 'P') ans = cmb.fact[a] / cmb.fact[a-b]; else ans = cmb(a+b-1, b); cout << ans << '\n'; } return 0; }