#include <bits/stdc++.h>
#define int long long
#define fi first
#define se second
using namespace std;
const int maxN = 3005;
const int mod = 1e9 + 7;
int n,m;
int f[maxN][maxN];
int32_t main()
{
ios_base::sync_with_stdio(false); cin.tie(); cout.tie();
cin >> m >> n;
for(int i = 0; i <= m; ++i)
f[i][0] = 1;
for(int i = 0; i <= n; ++i)
f[0][i] = 1;
for(int i = 1; i <= m; ++i){
for(int j = 1; j <= n; ++j){
f[i][j] = (f[i][j] + f[i - 1][j]) % mod;
f[i][j] = (f[i][j] + f[i - 1][j - 1] * 4 % mod * j % mod) % mod;
if(j >= 2)
f[i][j] = (f[i][j] + f[i - 1][j - 2] * (j*(j - 1)/2 % mod)) % mod;
if(i >= 2)
f[i][j] = (f[i][j] + f[i - 2][j - 1] * j % mod * (i - 1) % mod) % mod;
}
}
cout << (f[m][n] - 1 + mod) % mod;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
384 KB |
Output is correct |
2 |
Correct |
0 ms |
384 KB |
Output is correct |
3 |
Correct |
1 ms |
512 KB |
Output is correct |
4 |
Correct |
1 ms |
1152 KB |
Output is correct |
5 |
Correct |
1 ms |
768 KB |
Output is correct |
6 |
Correct |
1 ms |
1408 KB |
Output is correct |
7 |
Correct |
1 ms |
896 KB |
Output is correct |
8 |
Correct |
1 ms |
1536 KB |
Output is correct |
9 |
Correct |
1 ms |
896 KB |
Output is correct |
10 |
Correct |
2 ms |
1792 KB |
Output is correct |
11 |
Correct |
1 ms |
384 KB |
Output is correct |
12 |
Correct |
3 ms |
2304 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
384 KB |
Output is correct |
2 |
Correct |
0 ms |
384 KB |
Output is correct |
3 |
Correct |
1 ms |
512 KB |
Output is correct |
4 |
Correct |
1 ms |
1152 KB |
Output is correct |
5 |
Correct |
1 ms |
768 KB |
Output is correct |
6 |
Correct |
1 ms |
1408 KB |
Output is correct |
7 |
Correct |
1 ms |
896 KB |
Output is correct |
8 |
Correct |
1 ms |
1536 KB |
Output is correct |
9 |
Correct |
1 ms |
896 KB |
Output is correct |
10 |
Correct |
2 ms |
1792 KB |
Output is correct |
11 |
Correct |
1 ms |
384 KB |
Output is correct |
12 |
Correct |
3 ms |
2304 KB |
Output is correct |
13 |
Correct |
1 ms |
384 KB |
Output is correct |
14 |
Correct |
5 ms |
9728 KB |
Output is correct |
15 |
Correct |
139 ms |
55228 KB |
Output is correct |
16 |
Correct |
10 ms |
4096 KB |
Output is correct |
17 |
Correct |
31 ms |
12920 KB |
Output is correct |
18 |
Correct |
40 ms |
17144 KB |
Output is correct |
19 |
Correct |
165 ms |
62980 KB |
Output is correct |
20 |
Correct |
131 ms |
50936 KB |
Output is correct |
21 |
Correct |
86 ms |
33788 KB |
Output is correct |
22 |
Correct |
86 ms |
35576 KB |
Output is correct |
23 |
Correct |
51 ms |
27128 KB |
Output is correct |
24 |
Correct |
216 ms |
70904 KB |
Output is correct |
25 |
Correct |
174 ms |
61304 KB |
Output is correct |
26 |
Correct |
185 ms |
66808 KB |
Output is correct |
27 |
Correct |
204 ms |
68984 KB |
Output is correct |