結果
問題 | No.802 だいたい等差数列 |
ユーザー |
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提出日時 | 2019-03-17 22:49:15 |
言語 | C++14 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 107 ms / 2,000 ms |
コード長 | 3,981 bytes |
コンパイル時間 | 1,508 ms |
コンパイル使用メモリ | 171,376 KB |
実行使用メモリ | 50,304 KB |
最終ジャッジ日時 | 2024-07-08 01:15:06 |
合計ジャッジ時間 | 5,622 ms |
ジャッジサーバーID (参考情報) |
judge5 / judge2 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 4 |
other | AC * 30 |
ソースコード
#include <bits/stdc++.h>using namespace std;using lint = long long int;using pint = pair<int, int>;using plint = pair<lint, lint>;struct fast_ios { fast_ios(){ cin.tie(0); ios::sync_with_stdio(false); cout << fixed << setprecision(20); }; } fast_ios_;#define FOR(i, begin, end) for(int i=(begin),i##_end_=(end);i<i##_end_;i++)#define IFOR(i, begin, end) for(int i=(end)-1,i##_begin_=(begin);i>=i##_begin_;i--)#define REP(i, n) FOR(i,0,n)#define IREP(i, n) IFOR(i,0,n)template<typename T> istream &operator>>(istream &is, vector<T> &vec){ for (auto &v : vec) is >> v; return is; }template<typename T> ostream &operator<<(ostream &os, const vector<T> &vec){ os << "["; for (auto v : vec) os << v << ","; os << "]"; return os; }template<typename T> ostream &operator<<(ostream &os, const deque<T> &vec){ os << "deq["; for (auto v : vec) os << v << ","; os << "]"; return os; }template<typename T> ostream &operator<<(ostream &os, const set<T> &vec){ os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; }template<typename T> ostream &operator<<(ostream &os, const unordered_set<T> &vec){ os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; }template<typename T> ostream &operator<<(ostream &os, const multiset<T> &vec){ os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; }template<typename T> ostream &operator<<(ostream &os, const unordered_multiset<T> &vec){ os << "{"; for (auto v : vec) os << v << ","; os << "}";return os; }template<typename T1, typename T2> ostream &operator<<(ostream &os, const pair<T1, T2> &pa){ os << "(" << pa.first << "," << pa.second << ")"; returnos; }template<typename TK, typename TV> ostream &operator<<(ostream &os, const map<TK, TV> &mp){ os << "{"; for (auto v : mp) os << v.first << "=>" << v.second << ","; os << "}"; return os; }template<typename TK, typename TV> ostream &operator<<(ostream &os, const unordered_map<TK, TV> &mp){ os << "{"; for (auto v : mp) os << v.first << "=>" << v.second << ","; os << "}"; return os; }template<typename T> void ndarray(vector<T> &vec, int len) { vec.resize(len); }template<typename T, typename... Args> void ndarray(vector<T> &vec, int len, Args... args) { vec.resize(len); for (auto &v : vec) ndarray(v, args...);}template<typename T> bool mmax(T &m, const T q) { if (m < q) {m = q; return true;} else return false; }template<typename T> bool mmin(T &m, const T q) { if (m > q) {m = q; return true;} else return false; }template<typename T1, typename T2> pair<T1, T2> operator+(const pair<T1, T2> &l, const pair<T1, T2> &r) { return make_pair(l.first + r.first, l.second+ r.second); }template<typename T1, typename T2> pair<T1, T2> operator-(const pair<T1, T2> &l, const pair<T1, T2> &r) { return make_pair(l.first - r.first, l.second- r.second); }#define dbg(x) cerr << #x << " = " << (x) << " (L" << __LINE__ << ") " << __FILE__ << endl;#define FI first#define SE second#define ALL(x) (x).begin(), (x).end()#define SZ(x) ((lint)(x).size())#define POW2(n) (1LL << (n))constexpr lint MOD = 1000000007;vector<lint> fac, facInv, inv;void facInit(int nmax){fac = facInv = inv = vector<lint>(nmax + 1, 1);for (int i = 2; i <= nmax; i++){fac[i] = fac[i-1] * i % MOD;inv[i] = MOD - inv[MOD%i] * (MOD/i) % MOD;facInv[i] = facInv[i-1] * inv[i] % MOD;}}lint nCr(lint n, lint r){if (n<r || r<0) return 0;if (n >= (int)fac.size()) facInit(n);return (fac[n] * facInv[r] % MOD) * facInv[n-r] % MOD;}int main(){lint N, M, D1, D2;cin >> N >> M >> D1 >> D2;M = M - (N - 1) * D1;D2 = D2 - D1;if (M < 1){cout << 0 << endl;return 0;}facInit(2000000);lint ans = 0;REP(i, N) // 交差がD2より大きい地点の数{lint tmp = nCr(N - 1, i) * nCr(M - 1 + N - (D2 + 1) * i, N) % MOD;if (i % 2 == 0) ans += tmp; else ans += MOD - tmp;}cout << ans % MOD << endl;}