#include <iostream>
#include <vector>
#include <cassert>
using ll = long long;
int MOD = 998244353;
bool ckmax(auto &a, auto const& b) {return b>a?a=b,1:0;}
bool ckmin(auto &a, auto const& b) {return b<a?a=b,1:0;}
#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(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);}
friend mint pow(mint a, auto b) {
mint r(1);
for(;b;b>>=1, a*=a)
if(b&1)
r *= a;
return r;
}
};
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);
for(int i = 1;i <= N; ++i)
{
vector<mint> val_at(i + 1);
for(int j = 1;j <= i; ++j)
{
if(j >= 2) {
int ext = j - 2;
int nxt_i = i - 2 - ext;
if(nxt_i >= 0 && i * 2 - (j + 1) >= 0 && i * 2 - (j + 1) - ext >= 0)
val_at[j] += mint(j-1) * fac[i * 2 - (j + 1)] * invfac[i * 2 - (j + 1) - ext] * sum_dp[nxt_i];
}
int mid = j - 1;
if(i - mid >= 0 && (i * 2 - (j + 1) - mid) >= 0)
val_at[j] += dp[i - 1 - mid] * fac[i * 2 - (j + 1)] * invfac[i * 2 - (j + 1) - mid];
}
for(int j = sz(val_at) - 2;j >= 0;--j)
val_at[j] += val_at[j+1];
dp[i] = val_at[1];
for(int j = 1;j < sz(val_at); j++)
sum_dp[i] += val_at[j];
}
mint default_ans(1);
for(int i = N * 2 - 1;i >= 1; i -= 2)
default_ans *= mint(i);
printf("%d\n", (int)(default_ans - dp[N]));
return 0;
}
Compilation message
festival2.cpp:8:12: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
8 | bool ckmax(auto &a, auto const& b) {return b>a?a=b,1:0;}
| ^~~~
festival2.cpp:8:21: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
8 | bool ckmax(auto &a, auto const& b) {return b>a?a=b,1:0;}
| ^~~~
festival2.cpp:9:12: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
9 | bool ckmin(auto &a, auto const& b) {return b<a?a=b,1:0;}
| ^~~~
festival2.cpp:9:21: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
9 | bool ckmin(auto &a, auto const& b) {return b<a?a=b,1:0;}
| ^~~~
festival2.cpp:59:26: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
59 | friend mint pow(mint a, auto b) {
| ^~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
6 ms |
604 KB |
Output is correct |
2 |
Correct |
5 ms |
604 KB |
Output is correct |
3 |
Correct |
5 ms |
600 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 |
776 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
6 ms |
604 KB |
Output is correct |
2 |
Correct |
5 ms |
604 KB |
Output is correct |
3 |
Correct |
5 ms |
600 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 |
776 KB |
Output is correct |
8 |
Correct |
5 ms |
604 KB |
Output is correct |
9 |
Correct |
6 ms |
604 KB |
Output is correct |
10 |
Correct |
5 ms |
604 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 |
772 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
6 ms |
604 KB |
Output is correct |
2 |
Correct |
5 ms |
604 KB |
Output is correct |
3 |
Correct |
5 ms |
600 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 |
776 KB |
Output is correct |
8 |
Correct |
5 ms |
604 KB |
Output is correct |
9 |
Correct |
6 ms |
604 KB |
Output is correct |
10 |
Correct |
5 ms |
604 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 |
772 KB |
Output is correct |
14 |
Correct |
6 ms |
604 KB |
Output is correct |
15 |
Correct |
5 ms |
608 KB |
Output is correct |
16 |
Correct |
6 ms |
776 KB |
Output is correct |
17 |
Correct |
5 ms |
608 KB |
Output is correct |
18 |
Correct |
5 ms |
604 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
6 ms |
604 KB |
Output is correct |
2 |
Correct |
5 ms |
604 KB |
Output is correct |
3 |
Correct |
5 ms |
600 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 |
776 KB |
Output is correct |
8 |
Correct |
5 ms |
604 KB |
Output is correct |
9 |
Correct |
6 ms |
604 KB |
Output is correct |
10 |
Correct |
5 ms |
604 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 |
772 KB |
Output is correct |
14 |
Correct |
6 ms |
604 KB |
Output is correct |
15 |
Correct |
5 ms |
608 KB |
Output is correct |
16 |
Correct |
6 ms |
776 KB |
Output is correct |
17 |
Correct |
5 ms |
608 KB |
Output is correct |
18 |
Correct |
5 ms |
604 KB |
Output is correct |
19 |
Correct |
8 ms |
608 KB |
Output is correct |
20 |
Correct |
7 ms |
604 KB |
Output is correct |
21 |
Correct |
8 ms |
600 KB |
Output is correct |
22 |
Correct |
5 ms |
604 KB |
Output is correct |
23 |
Correct |
5 ms |
604 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
6 ms |
604 KB |
Output is correct |
2 |
Correct |
5 ms |
604 KB |
Output is correct |
3 |
Correct |
5 ms |
600 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 |
776 KB |
Output is correct |
8 |
Correct |
5 ms |
604 KB |
Output is correct |
9 |
Correct |
6 ms |
604 KB |
Output is correct |
10 |
Correct |
5 ms |
604 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 |
772 KB |
Output is correct |
14 |
Correct |
6 ms |
604 KB |
Output is correct |
15 |
Correct |
5 ms |
608 KB |
Output is correct |
16 |
Correct |
6 ms |
776 KB |
Output is correct |
17 |
Correct |
5 ms |
608 KB |
Output is correct |
18 |
Correct |
5 ms |
604 KB |
Output is correct |
19 |
Correct |
8 ms |
608 KB |
Output is correct |
20 |
Correct |
7 ms |
604 KB |
Output is correct |
21 |
Correct |
8 ms |
600 KB |
Output is correct |
22 |
Correct |
5 ms |
604 KB |
Output is correct |
23 |
Correct |
5 ms |
604 KB |
Output is correct |
24 |
Correct |
220 ms |
816 KB |
Output is correct |
25 |
Correct |
219 ms |
600 KB |
Output is correct |
26 |
Correct |
220 ms |
816 KB |
Output is correct |
27 |
Correct |
8 ms |
608 KB |
Output is correct |
28 |
Correct |
42 ms |
816 KB |
Output is correct |
29 |
Correct |
35 ms |
824 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
6 ms |
604 KB |
Output is correct |
2 |
Correct |
5 ms |
604 KB |
Output is correct |
3 |
Correct |
5 ms |
600 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 |
776 KB |
Output is correct |
8 |
Correct |
5 ms |
604 KB |
Output is correct |
9 |
Correct |
6 ms |
604 KB |
Output is correct |
10 |
Correct |
5 ms |
604 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 |
772 KB |
Output is correct |
14 |
Correct |
6 ms |
604 KB |
Output is correct |
15 |
Correct |
5 ms |
608 KB |
Output is correct |
16 |
Correct |
6 ms |
776 KB |
Output is correct |
17 |
Correct |
5 ms |
608 KB |
Output is correct |
18 |
Correct |
5 ms |
604 KB |
Output is correct |
19 |
Correct |
8 ms |
608 KB |
Output is correct |
20 |
Correct |
7 ms |
604 KB |
Output is correct |
21 |
Correct |
8 ms |
600 KB |
Output is correct |
22 |
Correct |
5 ms |
604 KB |
Output is correct |
23 |
Correct |
5 ms |
604 KB |
Output is correct |
24 |
Correct |
220 ms |
816 KB |
Output is correct |
25 |
Correct |
219 ms |
600 KB |
Output is correct |
26 |
Correct |
220 ms |
816 KB |
Output is correct |
27 |
Correct |
8 ms |
608 KB |
Output is correct |
28 |
Correct |
42 ms |
816 KB |
Output is correct |
29 |
Correct |
35 ms |
824 KB |
Output is correct |
30 |
Execution timed out |
9069 ms |
1508 KB |
Time limit exceeded |
31 |
Halted |
0 ms |
0 KB |
- |