#include <bits/stdc++.h>
#define oo 1000000007
#define ll long long
#define ld long double
#define ii pair<int, int>
#define pll pair<ll, ll>
#define ff first
#define ss second
#define mp make_pair
#define vi vector<int>
#define vii vector<ii>
#define isz(a) (int)(a.size())
#define pb push_back
#define fto(i, a, b) for (int i = (a); i <= (b); ++i)
#define fdto(i, a, b) for (int i = (a); i >= (b); --i)
#define bug(x) "["#x" = "<<(x)<<"] "
#define maxN 105
using namespace std;
const int MOD = oo;
int n, L, a[maxN];
ll f[maxN][maxN][1005][6];
int main() {
#ifdef LOCALME
freopen("JOI16_skyscraper.INP", "r", stdin);
freopen("JOI16_skyscraper.OUT", "w", stdout);
#endif
ios_base::sync_with_stdio(false); cin.tie(NULL);
cin >> n >> L;
fto(i, 1, n) cin >> a[i];
if (n == 1) return cout << "1\n", 1;
sort(a+1, a+n+1);
a[n+1] = 10000;
//f[1][1][2*a[2] - 2*a[1]][0] = f[1][1][a[2] - a[1]][1] = 1;
f[0][0][0][0] = 1;
fto(i, 1, n) {
fto(j, 1, i) {
fto(k, 0, L) {
fto(m, 0, 2) {
int delta = (2*j - m)*(a[i+1] - a[i]);
if (k < delta) continue;
f[i][j][k][m] = f[i-1][j][k - delta][m]*(2*j - m)%MOD;
f[i][j][k][m] = (f[i][j][k][m] + f[i-1][j-1][k - delta][m]*(j - m)) % MOD;
f[i][j][k][m] = (f[i][j][k][m] + f[i-1][j+1][k - delta][m]*j) % MOD;
if (m >= 1) {
f[i][j][k][m] = (f[i][j][k][m] + f[i-1][j][k - delta][m-1]*(3-m)) % MOD;
f[i][j][k][m] = (f[i][j][k][m] + f[i-1][j-1][k - delta][m-1]*(3-m)) % MOD;
}
// if (i == 2 && j == 1 && k == 4 && m == 1) {
// cerr << f[i-1][j][k - (2*j - m)*(a[i+1] - a[i])][m]*(2*j - m) << "\n"
// << f[i-1][j-1][k + (2*(j-1) - m)*a[i] - (2*j - m)*a[i+1] + 2*a[i]][m]*(j - m) << "\n"
// << f[i-1][j+1][k + (2*(j+1) - m)*a[i] - (2*j - m)*a[i+1] - 2*a[i]][m]*j << "\n"
// << f[i-1][j][k + (2*j - (m-1))*a[i] - (2*j - m)*a[i+1] - a[i]][m-1]*(3-m) << "\n"
// << f[i-1][j-1][k + (2*(j-1) - (m-1))*a[i] - (2*j - m)*a[i+1] + a[i]][m-1]*(3-m) << "\n";
// }
//
// if (f[i][j][k][m] != 0) cerr << bug(i) << bug(j) << bug(k) << bug(m) << bug(f[i][j][k][m]) << "\n";
}
}
}
}
int ans = 0;
fto(i, 1, L) ans = (ans + f[n][1][i][2]) % MOD;
cout << ans << "\n";
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
0 ms |
212 KB |
Execution failed because the return code was nonzero |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
724 KB |
Output is correct |
2 |
Correct |
1 ms |
852 KB |
Output is correct |
3 |
Correct |
1 ms |
852 KB |
Output is correct |
4 |
Correct |
1 ms |
852 KB |
Output is correct |
5 |
Correct |
1 ms |
852 KB |
Output is correct |
6 |
Correct |
1 ms |
980 KB |
Output is correct |
7 |
Correct |
1 ms |
724 KB |
Output is correct |
8 |
Correct |
1 ms |
852 KB |
Output is correct |
9 |
Correct |
1 ms |
980 KB |
Output is correct |
10 |
Correct |
1 ms |
724 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
0 ms |
212 KB |
Execution failed because the return code was nonzero |
2 |
Halted |
0 ms |
0 KB |
- |