#include <bits/stdc++.h>
#pragma GCC optimize ("O3")
#pragma GCC optimize ("unroll-loops")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,avx,avx2")
using namespace std;
typedef long long ll;
typedef __int128 lll;
typedef long double ld;
typedef pair<ll, ll> pll;
typedef pair<ld, ld> pld;
#define MAX 9223372036854775807LL
#define MIN -9223372036854775807LL
#define INF 0x3f3f3f3f3f3f3f3f
#define fi first
#define se second
#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL); cout << fixed; cout.precision(10);
#define sp << " "
#define en << "\n"
#define compress(v) sort(v.begin(), v.end()), v.erase(unique(v.begin(), v.end()), v.end())
ll n, m;
ll ss = 1000000007;
ll ans;
ll cou[2010];
ll dp[2010][2010];
ll fac[5010] = {0, }, inv[5010] = {0, };
ll power(ll xx, ll yy)
{
ll ret = 1;
while(yy > 0)
{
if(yy % 2)
ret = (ret * xx) % ss;
xx = (xx * xx) % ss;
yy /= 2;
}
return ret;
}
ll C(ll xx, ll yy)
{
if(xx < yy)
return 0;
if(xx == yy || !yy)
return 1;
long long r = (fac[xx] * inv[xx - yy]) % ss;
r = (r * inv[yy]) % ss;
return r;
}
void init(void)
{
fac[0] = 1;
fac[1] = 1;
for(ll i = 2 ; i <= 4500 ; i++)
fac[i] = (fac[i - 1] * i) % ss;
inv[4500] = power(fac[4500], ss - 2);
for(ll i = 4499 ; i >= 0 ; i--)
inv[i] = (inv[i + 1] * (i + 1)) % ss;
}
int main(void)
{
fastio
cin >> n >> m;
init();
ll siz = n * 2;
ans = fac[siz];
for(ll i = 1 ; i <= siz ; ++i)
{
ll gap = i % m;
if(gap == 0)
gap = m;
cou[gap]++;
}
for(ll i = 0 ; i <= m ; ++i)
dp[0][i] = 1;
for(ll i = 1 ; i <= n ; ++i)
{
for(ll j = 1 ; j <= m ; ++j)
{
ll X = cou[j];
for(ll k = 1 ; k * 2 <= X && k <= i ; ++k)
dp[i][j] = (dp[i][j] + dp[i - k][j - 1] * C(X, k * 2) % ss * fac[k * 2] % ss * C(i, k) % ss) % ss;
}
for(ll j = 1 ; j <= m ; ++j)
dp[i][j] = (dp[i][j] + dp[i][j - 1]) % ss;
}
for(ll i = 1 ; i <= n ; ++i)
{
ll gap = dp[i][m] * C(n, i) % ss * fac[n * 2 - i * 2] % ss;
if(i & 1)
ans = (ans - gap) % ss;
else
ans = (ans + gap) % ss;
}
ans = (ans + ss) % ss;
cout << ans;
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
600 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
348 KB |
Output is correct |
7 |
Correct |
0 ms |
344 KB |
Output is correct |
8 |
Correct |
1 ms |
344 KB |
Output is correct |
9 |
Correct |
0 ms |
344 KB |
Output is correct |
10 |
Correct |
0 ms |
348 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
600 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
348 KB |
Output is correct |
7 |
Correct |
0 ms |
344 KB |
Output is correct |
8 |
Correct |
1 ms |
344 KB |
Output is correct |
9 |
Correct |
0 ms |
344 KB |
Output is correct |
10 |
Correct |
0 ms |
348 KB |
Output is correct |
11 |
Correct |
1 ms |
860 KB |
Output is correct |
12 |
Correct |
1 ms |
604 KB |
Output is correct |
13 |
Correct |
1 ms |
604 KB |
Output is correct |
14 |
Correct |
1 ms |
604 KB |
Output is correct |
15 |
Correct |
1 ms |
860 KB |
Output is correct |
16 |
Correct |
1 ms |
860 KB |
Output is correct |
17 |
Correct |
1 ms |
600 KB |
Output is correct |
18 |
Correct |
1 ms |
600 KB |
Output is correct |
19 |
Correct |
1 ms |
860 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
600 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
348 KB |
Output is correct |
7 |
Correct |
0 ms |
344 KB |
Output is correct |
8 |
Correct |
1 ms |
344 KB |
Output is correct |
9 |
Correct |
0 ms |
344 KB |
Output is correct |
10 |
Correct |
0 ms |
348 KB |
Output is correct |
11 |
Correct |
1 ms |
860 KB |
Output is correct |
12 |
Correct |
1 ms |
604 KB |
Output is correct |
13 |
Correct |
1 ms |
604 KB |
Output is correct |
14 |
Correct |
1 ms |
604 KB |
Output is correct |
15 |
Correct |
1 ms |
860 KB |
Output is correct |
16 |
Correct |
1 ms |
860 KB |
Output is correct |
17 |
Correct |
1 ms |
600 KB |
Output is correct |
18 |
Correct |
1 ms |
600 KB |
Output is correct |
19 |
Correct |
1 ms |
860 KB |
Output is correct |
20 |
Correct |
2 ms |
1116 KB |
Output is correct |
21 |
Correct |
1 ms |
1116 KB |
Output is correct |
22 |
Correct |
3 ms |
2140 KB |
Output is correct |
23 |
Correct |
4 ms |
1396 KB |
Output is correct |
24 |
Correct |
4 ms |
1884 KB |
Output is correct |
25 |
Correct |
3 ms |
1884 KB |
Output is correct |
26 |
Correct |
4 ms |
1372 KB |
Output is correct |
27 |
Correct |
5 ms |
2396 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
600 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
348 KB |
Output is correct |
7 |
Correct |
0 ms |
344 KB |
Output is correct |
8 |
Correct |
1 ms |
344 KB |
Output is correct |
9 |
Correct |
0 ms |
344 KB |
Output is correct |
10 |
Correct |
0 ms |
348 KB |
Output is correct |
11 |
Correct |
1 ms |
860 KB |
Output is correct |
12 |
Correct |
1 ms |
604 KB |
Output is correct |
13 |
Correct |
1 ms |
604 KB |
Output is correct |
14 |
Correct |
1 ms |
604 KB |
Output is correct |
15 |
Correct |
1 ms |
860 KB |
Output is correct |
16 |
Correct |
1 ms |
860 KB |
Output is correct |
17 |
Correct |
1 ms |
600 KB |
Output is correct |
18 |
Correct |
1 ms |
600 KB |
Output is correct |
19 |
Correct |
1 ms |
860 KB |
Output is correct |
20 |
Correct |
2 ms |
1116 KB |
Output is correct |
21 |
Correct |
1 ms |
1116 KB |
Output is correct |
22 |
Correct |
3 ms |
2140 KB |
Output is correct |
23 |
Correct |
4 ms |
1396 KB |
Output is correct |
24 |
Correct |
4 ms |
1884 KB |
Output is correct |
25 |
Correct |
3 ms |
1884 KB |
Output is correct |
26 |
Correct |
4 ms |
1372 KB |
Output is correct |
27 |
Correct |
5 ms |
2396 KB |
Output is correct |
28 |
Correct |
23 ms |
2904 KB |
Output is correct |
29 |
Correct |
19 ms |
4700 KB |
Output is correct |
30 |
Correct |
16 ms |
5980 KB |
Output is correct |
31 |
Correct |
24 ms |
3060 KB |
Output is correct |
32 |
Correct |
22 ms |
4956 KB |
Output is correct |
33 |
Correct |
19 ms |
7004 KB |
Output is correct |
34 |
Correct |
32 ms |
10476 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
600 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
348 KB |
Output is correct |
7 |
Correct |
0 ms |
344 KB |
Output is correct |
8 |
Correct |
1 ms |
344 KB |
Output is correct |
9 |
Correct |
0 ms |
344 KB |
Output is correct |
10 |
Correct |
0 ms |
348 KB |
Output is correct |
11 |
Correct |
1 ms |
860 KB |
Output is correct |
12 |
Correct |
1 ms |
604 KB |
Output is correct |
13 |
Correct |
1 ms |
604 KB |
Output is correct |
14 |
Correct |
1 ms |
604 KB |
Output is correct |
15 |
Correct |
1 ms |
860 KB |
Output is correct |
16 |
Correct |
1 ms |
860 KB |
Output is correct |
17 |
Correct |
1 ms |
600 KB |
Output is correct |
18 |
Correct |
1 ms |
600 KB |
Output is correct |
19 |
Correct |
1 ms |
860 KB |
Output is correct |
20 |
Correct |
2 ms |
1116 KB |
Output is correct |
21 |
Correct |
1 ms |
1116 KB |
Output is correct |
22 |
Correct |
3 ms |
2140 KB |
Output is correct |
23 |
Correct |
4 ms |
1396 KB |
Output is correct |
24 |
Correct |
4 ms |
1884 KB |
Output is correct |
25 |
Correct |
3 ms |
1884 KB |
Output is correct |
26 |
Correct |
4 ms |
1372 KB |
Output is correct |
27 |
Correct |
5 ms |
2396 KB |
Output is correct |
28 |
Correct |
23 ms |
2904 KB |
Output is correct |
29 |
Correct |
19 ms |
4700 KB |
Output is correct |
30 |
Correct |
16 ms |
5980 KB |
Output is correct |
31 |
Correct |
24 ms |
3060 KB |
Output is correct |
32 |
Correct |
22 ms |
4956 KB |
Output is correct |
33 |
Correct |
19 ms |
7004 KB |
Output is correct |
34 |
Correct |
32 ms |
10476 KB |
Output is correct |
35 |
Correct |
147 ms |
7192 KB |
Output is correct |
36 |
Correct |
118 ms |
28392 KB |
Output is correct |
37 |
Correct |
144 ms |
7128 KB |
Output is correct |
38 |
Correct |
114 ms |
17816 KB |
Output is correct |
39 |
Correct |
94 ms |
25172 KB |
Output is correct |
40 |
Correct |
151 ms |
31828 KB |
Output is correct |