結果
| 問題 |
No.1302 Random Tree Score
|
| コンテスト | |
| ユーザー |
emthrm
|
| 提出日時 | 2020-11-27 23:13:49 |
| 言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
| 結果 |
WA
|
| 実行時間 | - |
| コード長 | 4,526 bytes |
| コンパイル時間 | 2,313 ms |
| コンパイル使用メモリ | 197,288 KB |
| 最終ジャッジ日時 | 2025-01-16 08:25:51 |
|
ジャッジサーバーID (参考情報) |
judge2 / judge1 |
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| ファイルパターン | 結果 |
|---|---|
| sample | WA * 2 TLE * 1 |
| other | AC * 1 WA * 1 TLE * 12 |
ソースコード
#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
using namespace std;
#define FOR(i,m,n) for(int i=(m);i<(n);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) (v).begin(),(v).end()
using ll = long long;
constexpr int INF = 0x3f3f3f3f;
constexpr long long LINF = 0x3f3f3f3f3f3f3f3fLL;
constexpr double EPS = 1e-8;
constexpr int MOD = 998244353;
constexpr int dy[] = {1, 0, -1, 0}, dx[] = {0, -1, 0, 1};
constexpr int dy8[] = {1, 1, 0, -1, -1, -1, 0, 1}, dx8[] = {0, -1, -1, -1, 0, 1, 1, 1};
template <typename T, typename U> inline bool chmax(T &a, U b) { return a < b ? (a = b, true) : false; }
template <typename T, typename U> inline bool chmin(T &a, U b) { return a > b ? (a = b, true) : false; }
struct IOSetup {
IOSetup() {
std::cin.tie(nullptr);
std::ios_base::sync_with_stdio(false);
std::cout << fixed << setprecision(20);
}
} iosetup;
template <int MOD>
struct MInt {
unsigned val;
MInt(): val(0) {}
MInt(long long x) : val(x >= 0 ? x % MOD : x % MOD + MOD) {}
static int get_mod() { return MOD; }
static void set_mod(int divisor) { assert(divisor == MOD); }
MInt pow(long long exponent) const {
MInt tmp = *this, res = 1;
while (exponent > 0) {
if (exponent & 1) res *= tmp;
tmp *= tmp;
exponent >>= 1;
}
return res;
}
MInt &operator+=(const MInt &x) { if((val += x.val) >= MOD) val -= MOD; return *this; }
MInt &operator-=(const MInt &x) { if((val += MOD - x.val) >= MOD) val -= MOD; return *this; }
MInt &operator*=(const MInt &x) { val = static_cast<unsigned long long>(val) * x.val % MOD; return *this; }
MInt &operator/=(const MInt &x) {
// assert(std::__gcd(static_cast<int>(x.val), MOD) == 1);
unsigned a = x.val, b = MOD; int u = 1, v = 0;
while (b) {
unsigned tmp = a / b;
std::swap(a -= tmp * b, b);
std::swap(u -= tmp * v, v);
}
return *this *= u;
}
bool operator==(const MInt &x) const { return val == x.val; }
bool operator!=(const MInt &x) const { return val != x.val; }
bool operator<(const MInt &x) const { return val < x.val; }
bool operator<=(const MInt &x) const { return val <= x.val; }
bool operator>(const MInt &x) const { return val > x.val; }
bool operator>=(const MInt &x) const { return val >= x.val; }
MInt &operator++() { if (++val == MOD) val = 0; return *this; }
MInt operator++(int) { MInt res = *this; ++*this; return res; }
MInt &operator--() { val = (val == 0 ? MOD : val) - 1; return *this; }
MInt operator--(int) { MInt res = *this; --*this; return res; }
MInt operator+() const { return *this; }
MInt operator-() const { return MInt(val ? MOD - val : 0); }
MInt operator+(const MInt &x) const { return MInt(*this) += x; }
MInt operator-(const MInt &x) const { return MInt(*this) -= x; }
MInt operator*(const MInt &x) const { return MInt(*this) *= x; }
MInt operator/(const MInt &x) const { return MInt(*this) /= x; }
friend std::ostream &operator<<(std::ostream &os, const MInt &x) { return os << x.val; }
friend std::istream &operator>>(std::istream &is, MInt &x) { long long val; is >> val; x = MInt(val); return is; }
};
namespace std { template <int MOD> MInt<MOD> abs(const MInt<MOD> &x) { return x; } }
template <int MOD>
struct Combinatorics {
using ModInt = MInt<MOD>;
int val; // "val!" and "mod" must be disjoint.
std::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 (int i = 1; i <= val; ++i) 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 (int i = 1; i <= val; ++i) inv[i] = fact[i - 1] * fact_inv[i];
}
ModInt nCk(int n, int k) const {
if (n < 0 || n < k || k < 0) return 0;
assert(n <= val && k <= val);
return fact[n] * fact_inv[k] * fact_inv[n - k];
}
ModInt nPk(int n, int k) const {
if (n < 0 || n < k || k < 0) return 0;
assert(n <= val);
return fact[n] * fact_inv[n - k];
}
ModInt nHk(int n, int k) const {
if (n < 0 || k < 0) return 0;
return k == 0 ? 1 : nCk(n + k - 1, k);
}
};
using ModInt = MInt<MOD>;
int main() {
int n; cin >> n;
Combinatorics<MOD> com(n);
vector<ModInt> dp(n - 1, 0);
dp[0] = 1;
REP(_, n) {
vector<ModInt> nx(n - 1, 0);
REP(i, n - 1) {
int rem = n - 2 - i;
REP(j, rem + 1) nx[i + j] += dp[i] * com.nCk(rem, j) * (j + 1);
}
dp.swap(nx);
}
cout << dp[n - 2] << '\n';
return 0;
}
emthrm