#include <bits/stdc++.h>
using namespace std;
#define lg long long
const lg N = 2e5+5, MOD = 1e9+7;
lg v[N], fact[N];
lg fast_power(lg n, lg k)
{
lg ans = 1;
while(k)
{
if((k&1))
{
ans = (ans*n)%MOD;
}
n = (n*n)%MOD;
k >>= 1;
}
return ans;
}
lg C(lg n, lg r)
{
lg ans = fact[n];
ans = (ans*fast_power(fact[r], MOD-2))%MOD;
ans = (ans*fast_power(fact[n-r], MOD-2))%MOD;
return ans;
}
lg dp[51][51][int(1e4+5)], fr[int(1e4+5)];
int main()
{
lg n, l;
cin >> n >> l;
fact[0] = 1;
for(lg i = 1; i <= 1e5; i++) fact[i] = (fact[i-1]*i)%MOD;
for(int i = 1; i <= n; i++) cin >> v[i];
sort(v+1, v+n+1);
dp[1][1][1] = 1;
for(int i = 1; i < n; i++)
{
for(int j = 1; j <= n; j++)
{
for(int k = 0; k <= l; k++)
{
if(k+v[i+1] <= 1e4) dp[i+1][j][k+v[i+1]] = (dp[i+1][j][k+v[i+1]]+(dp[i][j][k]*j*2ll)%MOD)%MOD;
if(j && k+v[i+1]*2 <= 1e4)
{
dp[i+1][j-1][k+v[i+1]*2] = (dp[i+1][j-1][k+v[i+1]*2]+(dp[i][j][k]*(j*(j-1))%MOD)%MOD)%MOD;
}
dp[i+1][j+1][k] = (dp[i+1][j+1][k]+dp[i][j][k])%MOD;
}
}
}
for(int i = 0; i <= l; i++) fr[i] = dp[n][1][i];
lg ans = 0;
for(lg i = 0; i <= l; i++)
{
lg cur = fr[i];
// cout << cur << ' ' << l-i+n << ' ' << n << '\n';
cur = (cur*C(l-i+n, n))%MOD;
ans = (ans+cur)%MOD;
}
cout << ans << '\n';
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
279 ms |
199732 KB |
Output is correct |
2 |
Correct |
7 ms |
15704 KB |
Output is correct |
3 |
Correct |
12 ms |
13400 KB |
Output is correct |
4 |
Correct |
5 ms |
5980 KB |
Output is correct |
5 |
Correct |
15 ms |
17220 KB |
Output is correct |
6 |
Correct |
71 ms |
66448 KB |
Output is correct |
7 |
Correct |
144 ms |
183632 KB |
Output is correct |
8 |
Correct |
2 ms |
4444 KB |
Output is correct |
9 |
Correct |
67 ms |
103768 KB |
Output is correct |
10 |
Correct |
2 ms |
4440 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
14 ms |
12892 KB |
Output is correct |
2 |
Correct |
3 ms |
5168 KB |
Output is correct |
3 |
Correct |
13 ms |
12888 KB |
Output is correct |
4 |
Correct |
4 ms |
5724 KB |
Output is correct |
5 |
Correct |
12 ms |
12892 KB |
Output is correct |
6 |
Correct |
4 ms |
6328 KB |
Output is correct |
7 |
Correct |
12 ms |
12800 KB |
Output is correct |
8 |
Correct |
3 ms |
5724 KB |
Output is correct |
9 |
Correct |
4 ms |
6236 KB |
Output is correct |
10 |
Correct |
2 ms |
4548 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
6 ms |
10584 KB |
Output is correct |
2 |
Correct |
3 ms |
7004 KB |
Output is correct |
3 |
Correct |
6 ms |
10588 KB |
Output is correct |
4 |
Correct |
4 ms |
7516 KB |
Output is correct |
5 |
Correct |
6 ms |
10588 KB |
Output is correct |
6 |
Correct |
2 ms |
6232 KB |
Output is correct |
7 |
Correct |
7 ms |
10588 KB |
Output is correct |
8 |
Correct |
2 ms |
5212 KB |
Output is correct |
9 |
Correct |
4 ms |
8028 KB |
Output is correct |
10 |
Correct |
2 ms |
5212 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
279 ms |
199732 KB |
Output is correct |
2 |
Correct |
7 ms |
15704 KB |
Output is correct |
3 |
Correct |
12 ms |
13400 KB |
Output is correct |
4 |
Correct |
5 ms |
5980 KB |
Output is correct |
5 |
Correct |
15 ms |
17220 KB |
Output is correct |
6 |
Correct |
71 ms |
66448 KB |
Output is correct |
7 |
Correct |
144 ms |
183632 KB |
Output is correct |
8 |
Correct |
2 ms |
4444 KB |
Output is correct |
9 |
Correct |
67 ms |
103768 KB |
Output is correct |
10 |
Correct |
2 ms |
4440 KB |
Output is correct |
11 |
Correct |
14 ms |
12892 KB |
Output is correct |
12 |
Correct |
3 ms |
5168 KB |
Output is correct |
13 |
Correct |
13 ms |
12888 KB |
Output is correct |
14 |
Correct |
4 ms |
5724 KB |
Output is correct |
15 |
Correct |
12 ms |
12892 KB |
Output is correct |
16 |
Correct |
4 ms |
6328 KB |
Output is correct |
17 |
Correct |
12 ms |
12800 KB |
Output is correct |
18 |
Correct |
3 ms |
5724 KB |
Output is correct |
19 |
Correct |
4 ms |
6236 KB |
Output is correct |
20 |
Correct |
2 ms |
4548 KB |
Output is correct |
21 |
Correct |
6 ms |
10584 KB |
Output is correct |
22 |
Correct |
3 ms |
7004 KB |
Output is correct |
23 |
Correct |
6 ms |
10588 KB |
Output is correct |
24 |
Correct |
4 ms |
7516 KB |
Output is correct |
25 |
Correct |
6 ms |
10588 KB |
Output is correct |
26 |
Correct |
2 ms |
6232 KB |
Output is correct |
27 |
Correct |
7 ms |
10588 KB |
Output is correct |
28 |
Correct |
2 ms |
5212 KB |
Output is correct |
29 |
Correct |
4 ms |
8028 KB |
Output is correct |
30 |
Correct |
2 ms |
5212 KB |
Output is correct |
31 |
Correct |
239 ms |
199844 KB |
Output is correct |
32 |
Correct |
157 ms |
137044 KB |
Output is correct |
33 |
Correct |
240 ms |
199704 KB |
Output is correct |
34 |
Correct |
51 ms |
49496 KB |
Output is correct |
35 |
Correct |
236 ms |
199848 KB |
Output is correct |
36 |
Correct |
20 ms |
17752 KB |
Output is correct |
37 |
Correct |
238 ms |
199792 KB |
Output is correct |
38 |
Correct |
43 ms |
46376 KB |
Output is correct |
39 |
Correct |
248 ms |
199584 KB |
Output is correct |
40 |
Correct |
77 ms |
66896 KB |
Output is correct |
41 |
Correct |
234 ms |
199728 KB |
Output is correct |
42 |
Correct |
4 ms |
6236 KB |
Output is correct |
43 |
Correct |
249 ms |
199660 KB |
Output is correct |
44 |
Correct |
26 ms |
26204 KB |
Output is correct |
45 |
Correct |
238 ms |
199740 KB |
Output is correct |
46 |
Correct |
4 ms |
4700 KB |
Output is correct |
47 |
Correct |
61 ms |
78936 KB |
Output is correct |
48 |
Correct |
47 ms |
63828 KB |
Output is correct |
49 |
Correct |
6 ms |
8028 KB |
Output is correct |
50 |
Correct |
2 ms |
5724 KB |
Output is correct |