#include <iostream>
#include <vector>
#include <cassert>
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);}
};
vector<mint> multiply(vector<mint> &&a, vector<mint> &&b) {
assert(a.size() >= 1);
assert(b.size() >= 1);
if(std::min(a.size(), b.size()) <= 16) {
vector<mint> ans(a.size() + b.size() - 1);
for(int i = 0;i < a.size(); ++i)
for(int j = 0;j < b.size(); ++j)
ans[i + j] += a[i] * b[j];
return ans;
}
else {
size_t fin_sz = a.size() + b.size() - 1;
if(a.size() < b.size()) a.resize(b.size());
if(b.size() < a.size()) b.resize(a.size());
// ((aH << m) + aL) * ((bH << m) + bL)
// = (aH * bH << m + m) + (aL * bL) + ((aH * bL << m) + (aL * bH << m))
// (aH * bL + aL * bH) = (aH + aL) * (bH + bL) - aH * bH - aL * bL;
int m = (a.size() + 1) / 2; // LOW size >= HI size
vector<mint> H = multiply({m+all(a)}, {m+all(b)});
vector<mint> L = multiply({a.begin(), a.begin() + m}, {b.begin(), b.begin() + m});
for(int i = 0;i + m < a.size(); ++i) a[i] += a[i+m], b[i] += b[i+m];
a.resize(m);
b.resize(m);
vector<mint> M = multiply(std::move(a), std::move(b));
assert(M.size() == L.size());
for(int i = 0;i < M.size(); ++i)
{
M[i] -= L[i];
if(i < H.size()) M[i] -= H[i];
}
vector<mint> ans = std::move(L);
ans.resize(fin_sz);
for(int i = 0;i < M.size() && i + m < fin_sz; ++i) ans[i+m] += M[i];
for(int i = 0;i < H.size() && i + 2*m < fin_sz; ++i) ans[i+2*m] += H[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:68:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<mint>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
68 | for(int i = 0;i < a.size(); ++i)
| ~~^~~~~~~~~~
festival2.cpp:69:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<mint>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
69 | for(int j = 0;j < b.size(); ++j)
| ~~^~~~~~~~~~
festival2.cpp:88:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<mint>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
88 | for(int i = 0;i + m < a.size(); ++i) a[i] += a[i+m], b[i] += b[i+m];
| ~~~~~~^~~~~~~~~~
festival2.cpp:94:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<mint>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
94 | for(int i = 0;i < M.size(); ++i)
| ~~^~~~~~~~~~
festival2.cpp:97:9: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<mint>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
97 | if(i < H.size()) M[i] -= H[i];
| ~~^~~~~~~~~~
festival2.cpp:102:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<mint>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
102 | for(int i = 0;i < M.size() && i + m < fin_sz; ++i) ans[i+m] += M[i];
| ~~^~~~~~~~~~
festival2.cpp:102:39: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
102 | for(int i = 0;i < M.size() && i + m < fin_sz; ++i) ans[i+m] += M[i];
| ~~~~~~^~~~~~~~
festival2.cpp:103:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<mint>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
103 | for(int i = 0;i < H.size() && i + 2*m < fin_sz; ++i) ans[i+2*m] += H[i];
| ~~^~~~~~~~~~
festival2.cpp:103:41: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare]
103 | for(int i = 0;i < H.size() && i + 2*m < fin_sz; ++i) ans[i+2*m] += H[i];
| ~~~~~~~~^~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
604 KB |
Output is correct |
2 |
Correct |
5 ms |
772 KB |
Output is correct |
3 |
Correct |
5 ms |
772 KB |
Output is correct |
4 |
Correct |
5 ms |
604 KB |
Output is correct |
5 |
Correct |
5 ms |
604 KB |
Output is correct |
6 |
Correct |
5 ms |
604 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 |
772 KB |
Output is correct |
3 |
Correct |
5 ms |
772 KB |
Output is correct |
4 |
Correct |
5 ms |
604 KB |
Output is correct |
5 |
Correct |
5 ms |
604 KB |
Output is correct |
6 |
Correct |
5 ms |
604 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 |
604 KB |
Output is correct |
10 |
Correct |
5 ms |
772 KB |
Output is correct |
11 |
Correct |
5 ms |
604 KB |
Output is correct |
12 |
Correct |
6 ms |
772 KB |
Output is correct |
13 |
Correct |
5 ms |
600 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
604 KB |
Output is correct |
2 |
Correct |
5 ms |
772 KB |
Output is correct |
3 |
Correct |
5 ms |
772 KB |
Output is correct |
4 |
Correct |
5 ms |
604 KB |
Output is correct |
5 |
Correct |
5 ms |
604 KB |
Output is correct |
6 |
Correct |
5 ms |
604 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 |
604 KB |
Output is correct |
10 |
Correct |
5 ms |
772 KB |
Output is correct |
11 |
Correct |
5 ms |
604 KB |
Output is correct |
12 |
Correct |
6 ms |
772 KB |
Output is correct |
13 |
Correct |
5 ms |
600 KB |
Output is correct |
14 |
Correct |
5 ms |
604 KB |
Output is correct |
15 |
Correct |
5 ms |
600 KB |
Output is correct |
16 |
Correct |
5 ms |
604 KB |
Output is correct |
17 |
Correct |
5 ms |
772 KB |
Output is correct |
18 |
Correct |
5 ms |
600 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
604 KB |
Output is correct |
2 |
Correct |
5 ms |
772 KB |
Output is correct |
3 |
Correct |
5 ms |
772 KB |
Output is correct |
4 |
Correct |
5 ms |
604 KB |
Output is correct |
5 |
Correct |
5 ms |
604 KB |
Output is correct |
6 |
Correct |
5 ms |
604 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 |
604 KB |
Output is correct |
10 |
Correct |
5 ms |
772 KB |
Output is correct |
11 |
Correct |
5 ms |
604 KB |
Output is correct |
12 |
Correct |
6 ms |
772 KB |
Output is correct |
13 |
Correct |
5 ms |
600 KB |
Output is correct |
14 |
Correct |
5 ms |
604 KB |
Output is correct |
15 |
Correct |
5 ms |
600 KB |
Output is correct |
16 |
Correct |
5 ms |
604 KB |
Output is correct |
17 |
Correct |
5 ms |
772 KB |
Output is correct |
18 |
Correct |
5 ms |
600 KB |
Output is correct |
19 |
Correct |
10 ms |
604 KB |
Output is correct |
20 |
Correct |
9 ms |
768 KB |
Output is correct |
21 |
Correct |
9 ms |
600 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 |
772 KB |
Output is correct |
3 |
Correct |
5 ms |
772 KB |
Output is correct |
4 |
Correct |
5 ms |
604 KB |
Output is correct |
5 |
Correct |
5 ms |
604 KB |
Output is correct |
6 |
Correct |
5 ms |
604 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 |
604 KB |
Output is correct |
10 |
Correct |
5 ms |
772 KB |
Output is correct |
11 |
Correct |
5 ms |
604 KB |
Output is correct |
12 |
Correct |
6 ms |
772 KB |
Output is correct |
13 |
Correct |
5 ms |
600 KB |
Output is correct |
14 |
Correct |
5 ms |
604 KB |
Output is correct |
15 |
Correct |
5 ms |
600 KB |
Output is correct |
16 |
Correct |
5 ms |
604 KB |
Output is correct |
17 |
Correct |
5 ms |
772 KB |
Output is correct |
18 |
Correct |
5 ms |
600 KB |
Output is correct |
19 |
Correct |
10 ms |
604 KB |
Output is correct |
20 |
Correct |
9 ms |
768 KB |
Output is correct |
21 |
Correct |
9 ms |
600 KB |
Output is correct |
22 |
Correct |
6 ms |
600 KB |
Output is correct |
23 |
Correct |
6 ms |
604 KB |
Output is correct |
24 |
Correct |
198 ms |
852 KB |
Output is correct |
25 |
Correct |
197 ms |
860 KB |
Output is correct |
26 |
Correct |
198 ms |
1104 KB |
Output is correct |
27 |
Correct |
10 ms |
604 KB |
Output is correct |
28 |
Correct |
51 ms |
808 KB |
Output is correct |
29 |
Correct |
43 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 |
772 KB |
Output is correct |
3 |
Correct |
5 ms |
772 KB |
Output is correct |
4 |
Correct |
5 ms |
604 KB |
Output is correct |
5 |
Correct |
5 ms |
604 KB |
Output is correct |
6 |
Correct |
5 ms |
604 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 |
604 KB |
Output is correct |
10 |
Correct |
5 ms |
772 KB |
Output is correct |
11 |
Correct |
5 ms |
604 KB |
Output is correct |
12 |
Correct |
6 ms |
772 KB |
Output is correct |
13 |
Correct |
5 ms |
600 KB |
Output is correct |
14 |
Correct |
5 ms |
604 KB |
Output is correct |
15 |
Correct |
5 ms |
600 KB |
Output is correct |
16 |
Correct |
5 ms |
604 KB |
Output is correct |
17 |
Correct |
5 ms |
772 KB |
Output is correct |
18 |
Correct |
5 ms |
600 KB |
Output is correct |
19 |
Correct |
10 ms |
604 KB |
Output is correct |
20 |
Correct |
9 ms |
768 KB |
Output is correct |
21 |
Correct |
9 ms |
600 KB |
Output is correct |
22 |
Correct |
6 ms |
600 KB |
Output is correct |
23 |
Correct |
6 ms |
604 KB |
Output is correct |
24 |
Correct |
198 ms |
852 KB |
Output is correct |
25 |
Correct |
197 ms |
860 KB |
Output is correct |
26 |
Correct |
198 ms |
1104 KB |
Output is correct |
27 |
Correct |
10 ms |
604 KB |
Output is correct |
28 |
Correct |
51 ms |
808 KB |
Output is correct |
29 |
Correct |
43 ms |
604 KB |
Output is correct |
30 |
Correct |
3852 ms |
1996 KB |
Output is correct |
31 |
Correct |
3945 ms |
1744 KB |
Output is correct |
32 |
Correct |
3894 ms |
1752 KB |
Output is correct |
33 |
Correct |
2393 ms |
1400 KB |
Output is correct |
34 |
Correct |
597 ms |
1040 KB |
Output is correct |
35 |
Correct |
509 ms |
968 KB |
Output is correct |