#include <bits/stdc++.h>
using namespace std;
int n, m;
long long dp[3007][3007];
const long long mod = 1e9 + 7;
int main(){
ios_base::sync_with_stdio(0);
cin >> n >> m;
for(int i = 0; i <= m; i++) dp[0][i] = 1;
for(int i = 0; i <= n; i++) dp[i][0] = 1;
for(int i = 1; i <= n; i++){
for(int j = 1; j <= m; j++){
dp[i][j] = (dp[i - 1][j] + 4LL * j * dp[i - 1][j - 1]) % mod;
if(i >= 2) dp[i][j] = (dp[i][j] + 1LL * (i - 1) * j * dp[i - 2][j - 1]) % mod;
if(j >= 2) dp[i][j] = (dp[i][j] + 1LL * j * (j - 1) / 2LL * dp[i - 1][j - 2]) % mod;
}
}
dp[n][m] = (dp[n][m] - 1 + mod) % mod;
cout << dp[n][m];
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
376 KB |
Output is correct |
2 |
Correct |
2 ms |
376 KB |
Output is correct |
3 |
Correct |
2 ms |
504 KB |
Output is correct |
4 |
Correct |
2 ms |
1144 KB |
Output is correct |
5 |
Correct |
2 ms |
760 KB |
Output is correct |
6 |
Correct |
3 ms |
1400 KB |
Output is correct |
7 |
Correct |
2 ms |
888 KB |
Output is correct |
8 |
Correct |
3 ms |
1528 KB |
Output is correct |
9 |
Correct |
2 ms |
760 KB |
Output is correct |
10 |
Correct |
3 ms |
1784 KB |
Output is correct |
11 |
Correct |
2 ms |
376 KB |
Output is correct |
12 |
Correct |
4 ms |
2296 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
376 KB |
Output is correct |
2 |
Correct |
2 ms |
376 KB |
Output is correct |
3 |
Correct |
2 ms |
504 KB |
Output is correct |
4 |
Correct |
2 ms |
1144 KB |
Output is correct |
5 |
Correct |
2 ms |
760 KB |
Output is correct |
6 |
Correct |
3 ms |
1400 KB |
Output is correct |
7 |
Correct |
2 ms |
888 KB |
Output is correct |
8 |
Correct |
3 ms |
1528 KB |
Output is correct |
9 |
Correct |
2 ms |
760 KB |
Output is correct |
10 |
Correct |
3 ms |
1784 KB |
Output is correct |
11 |
Correct |
2 ms |
376 KB |
Output is correct |
12 |
Correct |
4 ms |
2296 KB |
Output is correct |
13 |
Correct |
2 ms |
380 KB |
Output is correct |
14 |
Correct |
9 ms |
9720 KB |
Output is correct |
15 |
Correct |
80 ms |
55288 KB |
Output is correct |
16 |
Correct |
7 ms |
4092 KB |
Output is correct |
17 |
Correct |
22 ms |
12932 KB |
Output is correct |
18 |
Correct |
27 ms |
17144 KB |
Output is correct |
19 |
Correct |
100 ms |
62968 KB |
Output is correct |
20 |
Correct |
81 ms |
50860 KB |
Output is correct |
21 |
Correct |
54 ms |
33784 KB |
Output is correct |
22 |
Correct |
56 ms |
35480 KB |
Output is correct |
23 |
Correct |
37 ms |
27128 KB |
Output is correct |
24 |
Correct |
116 ms |
70904 KB |
Output is correct |
25 |
Correct |
192 ms |
61304 KB |
Output is correct |
26 |
Correct |
114 ms |
66680 KB |
Output is correct |
27 |
Correct |
113 ms |
69112 KB |
Output is correct |