Submission #956056

# Submission time Handle Problem Language Result Execution time Memory
956056 2024-03-31T23:58:24 Z frodakcin Festivals in JOI Kingdom 2 (JOI23_festival2) C++17
100 / 100
394 ms 6148 KB
#include <iostream>
#include <vector>
#include <cassert>
#include <complex>
using ll = long long;

int MOD = 998244353;

#ifdef LOCAL
template<typename T>
struct vector: std::vector<T> {
	template<typename... V> vector(V&&... args): std::vector<T>(std::forward<V>(args)...) {}
	T& operator [](size_t idx) {return vector::at(idx);}
	T const& operator[](size_t idx) const {return vector::at(idx);}
};
#else
using std::vector;
#endif
using std::pair, std::cin, std::cout;

#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define all(x) std::begin(x), std::end(x)
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;

ll euclid(ll a, ll b, ll &x, ll &y) {
	if (!b) return x = 1, y = 0, a;
	ll d = euclid(b, a % b, y, x);
	return y -= a/b * x, d;
}

struct mint {
	int v;
	explicit operator int() {return v;}
	mint(): v(0) {}
	mint(int z) {
		if(z < -MOD || MOD <= z) z %= MOD;
		if (z < 0) z += MOD;
		v = z;
	}
	mint(ll z) {
		z %= MOD;
		if (z < 0) z += MOD;
		v = z;
	}
	friend mint invert(mint a) {
		ll x, y, g = euclid(a.v, MOD, x, y);
		assert(g == 1); return mint(x);
	}
	mint& operator+= (mint const& o) {if((v+=o.v)>=MOD) v-=MOD; return *this;}
	mint& operator-= (mint const& o) {if((v-=o.v)<0) v+=MOD; return *this;}
	mint& operator*= (mint const& o) {v=(ll)v*o.v%MOD; return *this;}
	mint& operator/= (mint const& o) {return *this *= invert(o);}

	friend mint operator+ (mint a, mint const& b) {return a+=b;}
	friend mint operator- (mint a, mint const& b) {return a-=b;}
	friend mint operator* (mint a, mint const& b) {return a*=b;}
	friend mint operator/ (mint const& a, mint const& b) {return a*invert(b);}
};

using std::complex, std::imag, std::real, std::polar, std::acos;
using namespace std::complex_literals;
typedef complex<double> C;
typedef vector<double> vd;
void fft(vector<C>& a) {
	int n = sz(a), L = 31 - __builtin_clz(n);
	static vector<complex<long double>> R(2, 1);
	static vector<C> rt(2, 1);  // (^ 10% faster if double)
	for (static int k = 2; k < n; k *= 2) {
		R.resize(n); rt.resize(n);
		auto x = polar(1.0L, acos(-1.0L) / k);
		rep(i,k,2*k) rt[i] = R[i] = i&1 ? R[i/2] * x : R[i/2];
	}
	vi rev(n);
	rep(i,0,n) rev[i] = (rev[i / 2] | (i & 1) << L) / 2;
	rep(i,0,n) if (i < rev[i]) swap(a[i], a[rev[i]]);
	for (int k = 1; k < n; k *= 2)
		for (int i = 0; i < n; i += 2 * k) rep(j,0,k) {
			// C z = rt[j+k] * a[i+j+k]; // (25% faster if hand-rolled)  /// include-line
			auto x = (double *)&rt[j+k], y = (double *)&a[i+j+k];        /// exclude-line
			C z(x[0]*y[0] - x[1]*y[1], x[0]*y[1] + x[1]*y[0]);           /// exclude-line
			a[i + j + k] = a[i + j] - z;
			a[i + j] += z;
		}
}
vd conv(const vd& a, const vd& b) {
	if (a.empty() || b.empty()) return {};
	vd res(sz(a) + sz(b) - 1);
	int L = 32 - __builtin_clz(sz(res)), n = 1 << L;
	vector<C> in(n), out(n);
	copy(all(a), begin(in));
	rep(i,0,sz(b)) in[i].imag(b[i]);
	fft(in);
	for (C& x : in) x *= x;
	rep(i,0,n) out[i] = in[-i & (n - 1)] - conj(in[i]);
	fft(out);
	rep(i,0,sz(res)) res[i] = imag(out[i]) / (4 * n);
	return res;
}
typedef vector<ll> vl;
vl convMod(const vl &a, const vl &b) {
	if (a.empty() || b.empty()) return {};
	vl res(sz(a) + sz(b) - 1);
	int B=32-__builtin_clz(sz(res)), n=1<<B, cut=int(sqrt(MOD));
	vector<C> L(n), R(n), outs(n), outl(n);
	rep(i,0,sz(a)) L[i] = C((int)a[i] / cut, (int)a[i] % cut);
	rep(i,0,sz(b)) R[i] = C((int)b[i] / cut, (int)b[i] % cut);
	fft(L), fft(R);
	rep(i,0,n) {
		int j = -i & (n - 1);
		outl[j] = (L[i] + conj(L[j])) * R[i] / (2.0 * n);
		outs[j] = (L[i] - conj(L[j])) * R[i] / (2.0 * n) / 1i;
	}
	fft(outl), fft(outs);
	rep(i,0,sz(res)) {
		ll av = ll(real(outl[i])+.5), cv = ll(imag(outs[i])+.5);
		ll bv = ll(imag(outl[i])+.5) + ll(real(outs[i])+.5);
		res[i] = ((av % MOD * cut + bv) % MOD * cut + cv) % MOD;
	}
	return res;
}
vector<mint> multiply(vector<mint> &&a, vector<mint> &&b) {
	vl al, bl;
	al.resize(a.size());
	bl.resize(b.size());
	for(int i = 0;i < a.size(); ++i) al[i] = (int)a[i];
	for(int i = 0;i < b.size(); ++i) bl[i] = (int)b[i];
	vl res = convMod(al, bl);
	vector<mint> ans(res.size());
	for(int i = 0;i < ans.size(); ++i) ans[i] = mint(res[i]);
	return ans;
}

int const maxn = 2e4 + 10;
mint fac[2*maxn],invfac[2*maxn];

int main(){
	int N;
	cin.tie(0);cin.sync_with_stdio(0);
	cin >> N >> MOD;
	fac[0] = mint(1);invfac[0] = mint(1);
	for(int i=1; i<2*maxn; i++){
		fac[i] = (fac[i-1] * mint(i));
		invfac[i] = mint(1) / fac[i];
	}

	vector<mint> dp(N + 1);
	vector<mint> sum_dp(N + 1);

	dp[0] = mint(1);
	sum_dp[0] = mint(1);

	auto induce = [&](int l, int m, int r) {
		auto apply = [&](vector<mint>& ans, auto &&dep_i, auto &&dep_j, auto &&dep_i_j) {
			// ans[i] += fj(j) * fij(i+j)
			// => ans[K+i-1] += fj(K-j-1) * fij(i+j)
			// => ans[K+i-1 - (off)] += fj(K-j-1) * fij(i+j - off)

			int K = m;
			int off = l + m;

			vector<mint> f1(K - l);
			for(int j = l;j < m; ++j) f1[K - j - 1] = dep_j(j);
			vector<mint> f2;
			for(int ij = l + m;ij <= r + m - 2; ++ij) f2.push_back(dep_i_j(ij));

			vector<mint> res = multiply(std::move(f1), std::move(f2));

			for(int i = m;i < r; ++i)
				ans[i] += res[i + K - 1 - (off)] * dep_i(i);
		};

		apply(dp,
				[&](int i){return mint(1);},
				[&](int j){return dp[j]*invfac[2*j];},
				[&](int ij){return fac[ij-1];});

		apply(sum_dp,
				[&](int i){return mint(i);},
				[&](int j){return dp[j]*invfac[2*j];},
				[&](int ij){return fac[ij-1];});
		apply(sum_dp,
				[&](int i){return mint(1);},
				[&](int j){return dp[j]*invfac[2*j]*mint(-j);},
				[&](int ij){return fac[ij-1];});

		apply(dp,
				[&](int i){return mint(i);},
				[&](int j){return sum_dp[j]*invfac[2*j+1];},
				[&](int ij){return fac[ij-1];});
		apply(dp,
				[&](int i){return mint(1);},
				[&](int j){return sum_dp[j]*invfac[2*j+1]*mint(-j-1);},
				[&](int ij){return fac[ij-1];});

		apply(sum_dp,
				[&](int i){return mint(i) * mint(i) - mint(i);},
				[&](int j){return sum_dp[j]*invfac[2*j+1];},
				[&](int ij){return fac[ij-1];});
		apply(sum_dp,
				[&](int i){return mint(1);},
				[&](int j){return sum_dp[j]*invfac[2*j+1] * (mint(j) * mint(j) + mint(j));},
				[&](int ij){return fac[ij-1];});
		apply(sum_dp,
				[&](int i){return mint(-2*i);},
				[&](int j){return sum_dp[j]*invfac[2*j+1]*mint(j);},
				[&](int ij){return fac[ij-1];});
	};

	auto solve = [&](auto const& solve, int l, int r) ->void{
		if(l + 1 == r) return;
		int m = l + (r - l) / 2;
		solve(solve, l, m);
		induce(l, m, r);
		solve(solve, m, r);
	};
	solve(solve, 0, N + 1);

	mint default_ans(1);
	for(int i = N * 2 - 1;i >= 1; i -= 2)
		default_ans *= mint(i);
	
#ifdef LOCAL
	for(int i = 0;i <= N; ++i)
		printf("%d -- %d\n", dp[i], sum_dp[i]);
#endif
	printf("%d\n", (int)(default_ans - dp[N]));
	return 0;
}

Compilation message

festival2.cpp: In function 'std::vector<mint> multiply(std::vector<mint>&&, std::vector<mint>&&)':
festival2.cpp:128:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<mint>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  128 |  for(int i = 0;i < a.size(); ++i) al[i] = (int)a[i];
      |                ~~^~~~~~~~~~
festival2.cpp:129:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<mint>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  129 |  for(int i = 0;i < b.size(); ++i) bl[i] = (int)b[i];
      |                ~~^~~~~~~~~~
festival2.cpp:132:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<mint>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  132 |  for(int i = 0;i < ans.size(); ++i) ans[i] = mint(res[i]);
      |                ~~^~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 5 ms 604 KB Output is correct
2 Correct 5 ms 604 KB Output is correct
3 Correct 5 ms 604 KB Output is correct
4 Correct 5 ms 604 KB Output is correct
5 Correct 6 ms 604 KB Output is correct
6 Correct 5 ms 600 KB Output is correct
7 Correct 5 ms 604 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 5 ms 604 KB Output is correct
2 Correct 5 ms 604 KB Output is correct
3 Correct 5 ms 604 KB Output is correct
4 Correct 5 ms 604 KB Output is correct
5 Correct 6 ms 604 KB Output is correct
6 Correct 5 ms 600 KB Output is correct
7 Correct 5 ms 604 KB Output is correct
8 Correct 5 ms 604 KB Output is correct
9 Correct 5 ms 600 KB Output is correct
10 Correct 5 ms 604 KB Output is correct
11 Correct 5 ms 768 KB Output is correct
12 Correct 5 ms 768 KB Output is correct
13 Correct 5 ms 856 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 5 ms 604 KB Output is correct
2 Correct 5 ms 604 KB Output is correct
3 Correct 5 ms 604 KB Output is correct
4 Correct 5 ms 604 KB Output is correct
5 Correct 6 ms 604 KB Output is correct
6 Correct 5 ms 600 KB Output is correct
7 Correct 5 ms 604 KB Output is correct
8 Correct 5 ms 604 KB Output is correct
9 Correct 5 ms 600 KB Output is correct
10 Correct 5 ms 604 KB Output is correct
11 Correct 5 ms 768 KB Output is correct
12 Correct 5 ms 768 KB Output is correct
13 Correct 5 ms 856 KB Output is correct
14 Correct 5 ms 772 KB Output is correct
15 Correct 6 ms 600 KB Output is correct
16 Correct 5 ms 768 KB Output is correct
17 Correct 5 ms 604 KB Output is correct
18 Correct 6 ms 604 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 5 ms 604 KB Output is correct
2 Correct 5 ms 604 KB Output is correct
3 Correct 5 ms 604 KB Output is correct
4 Correct 5 ms 604 KB Output is correct
5 Correct 6 ms 604 KB Output is correct
6 Correct 5 ms 600 KB Output is correct
7 Correct 5 ms 604 KB Output is correct
8 Correct 5 ms 604 KB Output is correct
9 Correct 5 ms 600 KB Output is correct
10 Correct 5 ms 604 KB Output is correct
11 Correct 5 ms 768 KB Output is correct
12 Correct 5 ms 768 KB Output is correct
13 Correct 5 ms 856 KB Output is correct
14 Correct 5 ms 772 KB Output is correct
15 Correct 6 ms 600 KB Output is correct
16 Correct 5 ms 768 KB Output is correct
17 Correct 5 ms 604 KB Output is correct
18 Correct 6 ms 604 KB Output is correct
19 Correct 8 ms 604 KB Output is correct
20 Correct 8 ms 860 KB Output is correct
21 Correct 8 ms 764 KB Output is correct
22 Correct 6 ms 600 KB Output is correct
23 Correct 6 ms 604 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 5 ms 604 KB Output is correct
2 Correct 5 ms 604 KB Output is correct
3 Correct 5 ms 604 KB Output is correct
4 Correct 5 ms 604 KB Output is correct
5 Correct 6 ms 604 KB Output is correct
6 Correct 5 ms 600 KB Output is correct
7 Correct 5 ms 604 KB Output is correct
8 Correct 5 ms 604 KB Output is correct
9 Correct 5 ms 600 KB Output is correct
10 Correct 5 ms 604 KB Output is correct
11 Correct 5 ms 768 KB Output is correct
12 Correct 5 ms 768 KB Output is correct
13 Correct 5 ms 856 KB Output is correct
14 Correct 5 ms 772 KB Output is correct
15 Correct 6 ms 600 KB Output is correct
16 Correct 5 ms 768 KB Output is correct
17 Correct 5 ms 604 KB Output is correct
18 Correct 6 ms 604 KB Output is correct
19 Correct 8 ms 604 KB Output is correct
20 Correct 8 ms 860 KB Output is correct
21 Correct 8 ms 764 KB Output is correct
22 Correct 6 ms 600 KB Output is correct
23 Correct 6 ms 604 KB Output is correct
24 Correct 64 ms 1904 KB Output is correct
25 Correct 65 ms 1896 KB Output is correct
26 Correct 65 ms 1832 KB Output is correct
27 Correct 8 ms 860 KB Output is correct
28 Correct 21 ms 860 KB Output is correct
29 Correct 20 ms 860 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 5 ms 604 KB Output is correct
2 Correct 5 ms 604 KB Output is correct
3 Correct 5 ms 604 KB Output is correct
4 Correct 5 ms 604 KB Output is correct
5 Correct 6 ms 604 KB Output is correct
6 Correct 5 ms 600 KB Output is correct
7 Correct 5 ms 604 KB Output is correct
8 Correct 5 ms 604 KB Output is correct
9 Correct 5 ms 600 KB Output is correct
10 Correct 5 ms 604 KB Output is correct
11 Correct 5 ms 768 KB Output is correct
12 Correct 5 ms 768 KB Output is correct
13 Correct 5 ms 856 KB Output is correct
14 Correct 5 ms 772 KB Output is correct
15 Correct 6 ms 600 KB Output is correct
16 Correct 5 ms 768 KB Output is correct
17 Correct 5 ms 604 KB Output is correct
18 Correct 6 ms 604 KB Output is correct
19 Correct 8 ms 604 KB Output is correct
20 Correct 8 ms 860 KB Output is correct
21 Correct 8 ms 764 KB Output is correct
22 Correct 6 ms 600 KB Output is correct
23 Correct 6 ms 604 KB Output is correct
24 Correct 64 ms 1904 KB Output is correct
25 Correct 65 ms 1896 KB Output is correct
26 Correct 65 ms 1832 KB Output is correct
27 Correct 8 ms 860 KB Output is correct
28 Correct 21 ms 860 KB Output is correct
29 Correct 20 ms 860 KB Output is correct
30 Correct 387 ms 5920 KB Output is correct
31 Correct 394 ms 6148 KB Output is correct
32 Correct 388 ms 5920 KB Output is correct
33 Correct 336 ms 5644 KB Output is correct
34 Correct 140 ms 3056 KB Output is correct
35 Correct 128 ms 3184 KB Output is correct