/**
____ ____ ____ ____ ____ ____
||l |||e |||i |||n |||a |||d ||
||__|||__|||__|||__|||__|||__||
|/__\|/__\|/__\|/__\|/__\|/__\|
**/
#include<bits/stdc++.h>
#define endl '\n'
using namespace std;
typedef long long ll;
void speed()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
}
const int maxn = 110, maxl = 1e3 + 10;
const ll mod = 1e9 + 7;
int n, l, a[maxn];
void add(ll &cell, ll val)
{
val %= mod;
cell += val;
if (cell >= mod)
cell -= mod;
}
ll dp[maxn][maxl][maxn][3];
void solve()
{
cin >> n >> l;
for (int i = 1; i <= n; i ++)
cin >> a[i];
sort(a + 1, a + n + 1);
a[n + 1] = a[n];
if (n == 1)
{
cout << 1 << endl;
return;
}
if (n == 2)
{
if (a[2] - a[1] <= l)
{
cout << 2 << endl;
}
else
{
cout << 0 << endl;
}
return;
}
dp[1][2 * (a[2] - a[1])][1][0] = 1;
dp[1][a[2] - a[1]][1][1] = 1;
///cout << a[1] << " " << a[2] << endl;
for (int i = 1; i < n; i ++)
{
for (int j = 0; j <= l; j ++)
{
for (int k = 0; k <= n; k ++)
{
for (int p = 0; p < 3; p ++)
{
if (dp[i][j][k][p] == 0)
continue;
///cout << i << " " << j << " " << k << " " << p << " " << dp[i][j][k][p] << endl;
int new_diff = j + (k * 2 - p + 2) * (a[i + 2] - a[i + 1]); /// add a new component
///cout << new_diff << endl;
if (new_diff <= l)
add(dp[i + 1][new_diff][k + 1][p], dp[i][j][k][p] * (ll)(k + 1 - p));
new_diff = j + (k * 2 - p) * (a[i + 2] - a[i + 1]); /// add to an existing component
///cout << new_diff << endl;
if (new_diff <= l)
add(dp[i + 1][new_diff][k][p], dp[i][j][k][p] * (ll)((k * 2 - p)));
if (p != 2)
{
new_diff = j + (k * 2 - p - 1) * (a[i + 2] - a[i + 1]);
if (new_diff <= l)
add(dp[i + 1][new_diff][k][p + 1], dp[i][j][k][p]);
new_diff = j + (k * 2 - p + 1) * (a[i + 2] - a[i + 1]);
if (new_diff <= l)
add(dp[i + 1][new_diff][k + 1][p + 1], dp[i][j][k][p]);
}
new_diff = j + (k * 2 - p - 2) * (a[i + 2] - a[i + 1]);
//cout << i << " " << j << " " << k << " " << p << " " << dp[i][j][k][p] << endl;
// cout << new_diff << endl;
if (new_diff <= l && k > 1)
add(dp[i + 1][new_diff][k - 1][p], dp[i][j][k][p] * (k - 1));
}
}
}
}
ll ans = 0;
for (int s = 0; s <= l; s ++)
{
ans = ans + dp[n][s][1][2];
///cout << s << " :: " << dp[n][s][1][2] << endl;
if (ans >= mod)
ans -= mod;
}
cout << (ans * 2)% mod << endl;
}
int main()
{
solve();
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
312 KB |
Output is correct |
2 |
Correct |
0 ms |
212 KB |
Output is correct |
3 |
Correct |
1 ms |
340 KB |
Output is correct |
4 |
Correct |
1 ms |
596 KB |
Output is correct |
5 |
Correct |
3 ms |
816 KB |
Output is correct |
6 |
Correct |
3 ms |
1876 KB |
Output is correct |
7 |
Correct |
1 ms |
852 KB |
Output is correct |
8 |
Correct |
1 ms |
1080 KB |
Output is correct |
9 |
Correct |
5 ms |
2644 KB |
Output is correct |
10 |
Correct |
2 ms |
1492 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
1492 KB |
Output is correct |
2 |
Correct |
2 ms |
2104 KB |
Output is correct |
3 |
Correct |
2 ms |
1328 KB |
Output is correct |
4 |
Correct |
2 ms |
1876 KB |
Output is correct |
5 |
Correct |
2 ms |
1876 KB |
Output is correct |
6 |
Correct |
2 ms |
2260 KB |
Output is correct |
7 |
Correct |
1 ms |
852 KB |
Output is correct |
8 |
Correct |
1 ms |
1332 KB |
Output is correct |
9 |
Correct |
2 ms |
1876 KB |
Output is correct |
10 |
Correct |
2 ms |
1876 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
312 KB |
Output is correct |
2 |
Correct |
0 ms |
212 KB |
Output is correct |
3 |
Correct |
1 ms |
340 KB |
Output is correct |
4 |
Correct |
1 ms |
596 KB |
Output is correct |
5 |
Correct |
3 ms |
816 KB |
Output is correct |
6 |
Correct |
3 ms |
1876 KB |
Output is correct |
7 |
Correct |
1 ms |
852 KB |
Output is correct |
8 |
Correct |
1 ms |
1080 KB |
Output is correct |
9 |
Correct |
5 ms |
2644 KB |
Output is correct |
10 |
Correct |
2 ms |
1492 KB |
Output is correct |
11 |
Correct |
1 ms |
1492 KB |
Output is correct |
12 |
Correct |
2 ms |
2104 KB |
Output is correct |
13 |
Correct |
2 ms |
1328 KB |
Output is correct |
14 |
Correct |
2 ms |
1876 KB |
Output is correct |
15 |
Correct |
2 ms |
1876 KB |
Output is correct |
16 |
Correct |
2 ms |
2260 KB |
Output is correct |
17 |
Correct |
1 ms |
852 KB |
Output is correct |
18 |
Correct |
1 ms |
1332 KB |
Output is correct |
19 |
Correct |
2 ms |
1876 KB |
Output is correct |
20 |
Correct |
2 ms |
1876 KB |
Output is correct |
21 |
Correct |
2 ms |
2388 KB |
Output is correct |
22 |
Correct |
129 ms |
122188 KB |
Output is correct |
23 |
Correct |
151 ms |
105548 KB |
Output is correct |
24 |
Correct |
139 ms |
115488 KB |
Output is correct |
25 |
Correct |
141 ms |
117316 KB |
Output is correct |
26 |
Correct |
124 ms |
101232 KB |
Output is correct |
27 |
Correct |
48 ms |
45712 KB |
Output is correct |
28 |
Correct |
59 ms |
57908 KB |
Output is correct |
29 |
Correct |
115 ms |
107748 KB |
Output is correct |
30 |
Correct |
138 ms |
117828 KB |
Output is correct |