#pragma GCC optimize ("O3")
#include <bits/stdc++.h>
//#include<ext/pb_ds/assoc_container.hpp>
//#include<ext/pb_ds/tree_policy.hpp>
#define pii pair<int, int>
#define piii pair<pii, int>
#define vi vector<int>
#define vll vector<ll>
#define vvi vector<vi>
#define vpii vector<pii>
#define vvpii vector<vpii>
#define f first
#define s second
#define oo 1000000001
#define eb emplace_back
#define pb push_back
#define mpr make_pair
#define size(v) (int)v.size()
#define ln '\n'
#define ull unsigned long long
#define ll long long
#define all(v) v.begin(), v.end()
#define iospeed ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0)
using namespace std;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
//using namespace __gnu_pbds;
//template <typename T>
//using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template <typename T>
void show(vector<T> &v) {
for (T i : v) {
cout << i << ' ';
}
cout << ln;
}
const int MAXN = 102;
const int MAXL = 1003;
const int MOD = 1e9 + 7;
int dp[MAXN][MAXN][MAXL][3];
void solve() {
int n, l;
cin >> n >> l;
vi a(n + 1);
for (int i = 1; i <= n; ++i) {
cin >> a[i];
}
if (n == 1) {
cout << (a[1] <= l ? 1 : 0) << ln;
return;
}
sort(a.begin() + 1, a.end());
dp[0][0][0][0] = 1;
for (int i = 1; i <= n; ++i) {
int diff = (i == n ? 0 : a[i + 1] - a[i]);
for (int j = 0; j < i; ++j) {
for (int s = 0; s <= l; ++s) {
for (int k = 0; k < 3; ++k) {
if (!dp[i - 1][j][s][k]) continue;
int sum = s + (2 * j + 2 - k) * diff;
if (sum <= l) dp[i][j + 1][sum][k] = (1ll * (j + 1 - k) * dp[i - 1][j][s][k] + dp[i][j + 1][sum][k]) % MOD; // new group (not an end position)
if (k < 2) {
sum = s + (2 * j + 1 - k) * diff;
if (sum <= l) dp[i][j + 1][sum][k + 1] = (1ll * (2 - k) * dp[i - 1][j][s][k] + dp[i][j + 1][sum][k + 1]) % MOD; // new group (an end position)
}
if (j) {
sum = s + (2 * j - k) * diff;
if (sum <= l) dp[i][j][sum][k] = (1ll * (2 * j - k) * dp[i - 1][j][s][k] + dp[i][j][sum][k]) % MOD; // next to a group (not an end position)
if (k < 2) {
sum = s + (2 * j - k - 1) * diff;
if (sum <= l) dp[i][j][sum][k + 1] = (1ll * (2 - k) * dp[i - 1][j][s][k] + dp[i][j][sum][k + 1]) % MOD; // next to a group (an end position)
}
}
if (j >= 2) {
sum = s + (2 * j - 2 - k) * diff;
if (sum <= l) dp[i][j - 1][sum][k] = (1ll * (j - 1) * dp[i - 1][j][s][k] + dp[i][j - 1][sum][k]) % MOD; // combine two groups
}
}
}
}
}
int res = 0;
for (int i = 0; i <= l; ++i) {
res += dp[n][1][i][2];
if (res >= MOD) res -= MOD;
}
cout << res << ln;
}
int main() {
iospeed;
solve();
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
1 ms |
344 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
604 KB |
Output is correct |
2 |
Correct |
0 ms |
604 KB |
Output is correct |
3 |
Correct |
1 ms |
604 KB |
Output is correct |
4 |
Correct |
1 ms |
604 KB |
Output is correct |
5 |
Correct |
0 ms |
604 KB |
Output is correct |
6 |
Correct |
1 ms |
604 KB |
Output is correct |
7 |
Correct |
1 ms |
604 KB |
Output is correct |
8 |
Correct |
1 ms |
604 KB |
Output is correct |
9 |
Correct |
1 ms |
604 KB |
Output is correct |
10 |
Correct |
1 ms |
604 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
1 ms |
344 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |