#include <bits/stdc++.h>
using namespace std;
#define mp make_pair
#define fi first
#define se second
#define all(x) x.begin(), x.end()
#define getbit(x, i) (((x) >> (i)) & 1)
#define bit(x) (1 << (x))
#define popcount __builtin_popcountll
mt19937_64 rd(chrono::steady_clock::now().time_since_epoch().count());
long long rand(long long l, long long r) {
return l + rd() % (r - l + 1);
}
const int N = 1e6 + 5;
const int mod = 1e9 + 7; // 998244353;
const int lg = 25; // lg + 1
const int inf = 1e9; // INT_MAX;
const long long llinf = 1e18; // LLONG_MAX;
template<class X, class Y>
bool minimize(X &a, Y b) {
return a > b ? (a = b, true) : false;
}
template<class X, class Y>
bool maximize(X &a, Y b) {
return a < b ? (a = b, true) : false;
}
template<class X, class Y>
bool add(X &a, Y b) {
a += b;
while (a >= mod) a -= mod;
while (a < 0) a += mod;
return true;
}
const int MAX_N = 50 + 5;
const int MAX_L = 1e4 + 5;
int n, l;
int a[N];
int f[MAX_N][MAX_N][MAX_L];
int pw(int x, int y) {
int res = 1;
while (y) {
if (y & 1) res = 1LL * res * x % mod;
x = 1LL * x * x % mod;
y >>= 1;
}
return res % mod;
}
int fac[N], inv[N];
void pre() {
int n = 1e6;
fac[0] = 1;
for (int i = 1; i <= n; ++i) fac[i] = 1LL * fac[i - 1] * i % mod;
inv[n] = pw(fac[n], mod - 2);
for (int i = n; i >= 1; --i) inv[i - 1] = 1LL * inv[i] * i % mod;
}
int nCk(int n, int k) {
if (k > n || k < 0) return 0;
return 1LL * fac[n] * inv[k] % mod * inv[n - k] % mod;
}
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
pre();
cin >> n >> l;
for (int i = 1; i <= n; ++i)
cin >> a[i];
sort(a + 1, a + n + 1);
f[0][0][0] = 1;
for (int i = 1; i <= n; ++i)
for (int j = 1; j <= i; ++j)
for (int k = 1; k <= l; ++k) {
int r = a[i];
// new component
f[i][j][k] = f[i - 1][j - 1][k - 1];
// append
if (k - r >= 0)
add(f[i][j][k], 1LL * f[i - 1][j][k - r] * 2 * j % mod);
// join
// (r - 1) + (r - 1) + 1 = 2r - 1
if (k - 2 * r + 1 >= 0)
add(f[i][j][k], 1LL * f[i - 1][j + 1][k - 2 * r + 1] * j * (j + 1) % mod);
}
int res = 0;
for (int i = 1; i <= l; ++i)
add(res, 1LL * f[n][1][i] * nCk(n + l - i, n) % mod);
cout << res;
return 0;
}
/*
*/
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
89 ms |
121668 KB |
Output is correct |
2 |
Correct |
22 ms |
121692 KB |
Output is correct |
3 |
Correct |
16 ms |
35420 KB |
Output is correct |
4 |
Correct |
12 ms |
20956 KB |
Output is correct |
5 |
Correct |
20 ms |
57940 KB |
Output is correct |
6 |
Correct |
35 ms |
72284 KB |
Output is correct |
7 |
Correct |
32 ms |
117572 KB |
Output is correct |
8 |
Correct |
11 ms |
12892 KB |
Output is correct |
9 |
Correct |
21 ms |
90716 KB |
Output is correct |
10 |
Correct |
11 ms |
12892 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
16 ms |
33372 KB |
Output is correct |
2 |
Correct |
11 ms |
16988 KB |
Output is correct |
3 |
Correct |
15 ms |
33372 KB |
Output is correct |
4 |
Correct |
12 ms |
21084 KB |
Output is correct |
5 |
Correct |
16 ms |
33424 KB |
Output is correct |
6 |
Correct |
13 ms |
25180 KB |
Output is correct |
7 |
Correct |
16 ms |
33372 KB |
Output is correct |
8 |
Correct |
13 ms |
33248 KB |
Output is correct |
9 |
Correct |
12 ms |
23132 KB |
Output is correct |
10 |
Correct |
11 ms |
12892 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
18 ms |
76380 KB |
Output is correct |
2 |
Correct |
16 ms |
56024 KB |
Output is correct |
3 |
Correct |
18 ms |
76516 KB |
Output is correct |
4 |
Correct |
16 ms |
57948 KB |
Output is correct |
5 |
Correct |
18 ms |
76380 KB |
Output is correct |
6 |
Correct |
15 ms |
53852 KB |
Output is correct |
7 |
Correct |
18 ms |
76380 KB |
Output is correct |
8 |
Correct |
13 ms |
33460 KB |
Output is correct |
9 |
Correct |
15 ms |
57948 KB |
Output is correct |
10 |
Correct |
13 ms |
33432 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
89 ms |
121668 KB |
Output is correct |
2 |
Correct |
22 ms |
121692 KB |
Output is correct |
3 |
Correct |
16 ms |
35420 KB |
Output is correct |
4 |
Correct |
12 ms |
20956 KB |
Output is correct |
5 |
Correct |
20 ms |
57940 KB |
Output is correct |
6 |
Correct |
35 ms |
72284 KB |
Output is correct |
7 |
Correct |
32 ms |
117572 KB |
Output is correct |
8 |
Correct |
11 ms |
12892 KB |
Output is correct |
9 |
Correct |
21 ms |
90716 KB |
Output is correct |
10 |
Correct |
11 ms |
12892 KB |
Output is correct |
11 |
Correct |
16 ms |
33372 KB |
Output is correct |
12 |
Correct |
11 ms |
16988 KB |
Output is correct |
13 |
Correct |
15 ms |
33372 KB |
Output is correct |
14 |
Correct |
12 ms |
21084 KB |
Output is correct |
15 |
Correct |
16 ms |
33424 KB |
Output is correct |
16 |
Correct |
13 ms |
25180 KB |
Output is correct |
17 |
Correct |
16 ms |
33372 KB |
Output is correct |
18 |
Correct |
13 ms |
33248 KB |
Output is correct |
19 |
Correct |
12 ms |
23132 KB |
Output is correct |
20 |
Correct |
11 ms |
12892 KB |
Output is correct |
21 |
Correct |
18 ms |
76380 KB |
Output is correct |
22 |
Correct |
16 ms |
56024 KB |
Output is correct |
23 |
Correct |
18 ms |
76516 KB |
Output is correct |
24 |
Correct |
16 ms |
57948 KB |
Output is correct |
25 |
Correct |
18 ms |
76380 KB |
Output is correct |
26 |
Correct |
15 ms |
53852 KB |
Output is correct |
27 |
Correct |
18 ms |
76380 KB |
Output is correct |
28 |
Correct |
13 ms |
33460 KB |
Output is correct |
29 |
Correct |
15 ms |
57948 KB |
Output is correct |
30 |
Correct |
13 ms |
33432 KB |
Output is correct |
31 |
Correct |
100 ms |
121516 KB |
Output is correct |
32 |
Correct |
78 ms |
111300 KB |
Output is correct |
33 |
Correct |
105 ms |
121664 KB |
Output is correct |
34 |
Correct |
31 ms |
70224 KB |
Output is correct |
35 |
Correct |
99 ms |
121564 KB |
Output is correct |
36 |
Correct |
17 ms |
41564 KB |
Output is correct |
37 |
Correct |
102 ms |
121536 KB |
Output is correct |
38 |
Correct |
33 ms |
117332 KB |
Output is correct |
39 |
Correct |
96 ms |
121588 KB |
Output is correct |
40 |
Correct |
35 ms |
72272 KB |
Output is correct |
41 |
Correct |
90 ms |
121684 KB |
Output is correct |
42 |
Correct |
13 ms |
29272 KB |
Output is correct |
43 |
Correct |
87 ms |
121684 KB |
Output is correct |
44 |
Correct |
21 ms |
53852 KB |
Output is correct |
45 |
Correct |
86 ms |
121684 KB |
Output is correct |
46 |
Correct |
11 ms |
14940 KB |
Output is correct |
47 |
Correct |
23 ms |
78596 KB |
Output is correct |
48 |
Correct |
21 ms |
94812 KB |
Output is correct |
49 |
Correct |
13 ms |
27228 KB |
Output is correct |
50 |
Correct |
13 ms |
35420 KB |
Output is correct |