/** I can do this all day **/
#pragma GCC optimize("Ofast")
#pragma GCC target("avx")
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
#define all(x) (x).begin(),(x).end()
#define F first
#define S second
#define Mp make_pair
#define SZ(x) (int)x.size()
#define fast_io ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define file_io freopen("in.txt" , "r+" , stdin) ; freopen("out.txt" , "w+" , stdout);
const int N = 1e2 + 10;
const ll mod = 1e9 + 7;
const ll mod2 = 998244353;
const ll inf = 8e18;
const int LOG = 22;
const int MXL = 1e3 + 10;
int n, L, A[N];
ll dp[2][2][2][N][MXL]; /// dp[i][left][right][j][k] -> tedad halati ke i taye aval j ta moalefe ke left left baste ast ya na va hamintor right ba sigma delta = k
ll tot;
int main()
{
scanf("%d%d", &n, &L);
for(int i = 1; i <= n; i ++)
{
scanf("%d", &A[i]);
}
if(n == 1) { return !printf("1"); }
sort(A + 1, A + n + 1);
dp[0][0][0][0][0] = 1;
for(int i = 0; i < n; i ++)
{
int I = i & 1, I2 = I ^ 1;
memset(dp[I2], 0, sizeof dp[I2]);
for(int l = 0; l < 2; l ++)
{
for(int r = 0; r < 2; r ++)
{
for(int j = 0; j <= i; j ++)
{
for(int k = 0; k <= L; k ++)
{
if(dp[I][l][r][j][k] == 0) continue;
ll cu = dp[I][l][r][j][k];
int k2 = k + (2 * j - l - r) * (A[i + 1] - A[i]);
///printf("here i = %d j = %d k = %d l = %d r = %d cu = %lld\n", i, j, k, l, r, cu);
if(k2 > L) continue;
if(l == 0)
{
if(j) dp[I2][1][r][j][k2] = (dp[I2][1][r][j][k2] + cu) % mod; /// bechasbe be left hazer L fix
dp[I2][1][r][j + 1][k2] = (dp[I2][1][r][j + 1][k2] + cu) % mod; /// L beshe fix moalefe jadid
}
if(r == 0)
{
if(j) dp[I2][l][1][j][k2] = (dp[I2][l][1][j][k2] + cu) % mod; /// bechasbe be right hazer R fix
dp[I2][l][1][j + 1][k2] = (dp[I2][l][1][j + 1][k2] + cu) % mod; /// R beshe fix moalefe jadid
}
/// moalefe jadid
dp[I2][l][r][j + 1][k2] = (dp[I2][l][r][j + 1][k2] + cu * (j + 1 - l - r)) % mod;
/// bechasbe be yeki
dp[I2][l][r][j][k2] = (dp[I2][l][r][j][k2] + cu * (2 * j - l - r)) % mod;
/// bechasbe be dota
if(j) dp[I2][l][r][j - 1][k2] = (dp[I2][l][r][j - 1][k2] + cu * (j - 1)) % mod;
}
}
}
}
}
for(int k = 0; k <= L; k ++)
{
tot = (tot + dp[n & 1][1][1][1][k]) % mod;
}
printf("%lld", tot);
return 0;
}
/** test corner cases(n = 1?) watch for overflow or minus indices **/
Compilation message
skyscraper.cpp: In function 'int main()':
skyscraper.cpp:35:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
35 | scanf("%d%d", &n, &L);
| ~~~~~^~~~~~~~~~~~~~~~
skyscraper.cpp:38:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
38 | scanf("%d", &A[i]);
| ~~~~~^~~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
300 KB |
Output is correct |
2 |
Correct |
3 ms |
7244 KB |
Output is correct |
3 |
Correct |
4 ms |
7244 KB |
Output is correct |
4 |
Correct |
5 ms |
7244 KB |
Output is correct |
5 |
Correct |
5 ms |
7244 KB |
Output is correct |
6 |
Correct |
5 ms |
7244 KB |
Output is correct |
7 |
Correct |
5 ms |
7244 KB |
Output is correct |
8 |
Correct |
5 ms |
7252 KB |
Output is correct |
9 |
Correct |
6 ms |
7244 KB |
Output is correct |
10 |
Correct |
5 ms |
7244 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
6 ms |
7244 KB |
Output is correct |
2 |
Correct |
10 ms |
7244 KB |
Output is correct |
3 |
Correct |
7 ms |
7244 KB |
Output is correct |
4 |
Correct |
9 ms |
7372 KB |
Output is correct |
5 |
Correct |
9 ms |
7244 KB |
Output is correct |
6 |
Correct |
7 ms |
7244 KB |
Output is correct |
7 |
Correct |
7 ms |
7252 KB |
Output is correct |
8 |
Correct |
6 ms |
7212 KB |
Output is correct |
9 |
Correct |
7 ms |
7244 KB |
Output is correct |
10 |
Correct |
7 ms |
7244 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
300 KB |
Output is correct |
2 |
Correct |
3 ms |
7244 KB |
Output is correct |
3 |
Correct |
4 ms |
7244 KB |
Output is correct |
4 |
Correct |
5 ms |
7244 KB |
Output is correct |
5 |
Correct |
5 ms |
7244 KB |
Output is correct |
6 |
Correct |
5 ms |
7244 KB |
Output is correct |
7 |
Correct |
5 ms |
7244 KB |
Output is correct |
8 |
Correct |
5 ms |
7252 KB |
Output is correct |
9 |
Correct |
6 ms |
7244 KB |
Output is correct |
10 |
Correct |
5 ms |
7244 KB |
Output is correct |
11 |
Correct |
6 ms |
7244 KB |
Output is correct |
12 |
Correct |
10 ms |
7244 KB |
Output is correct |
13 |
Correct |
7 ms |
7244 KB |
Output is correct |
14 |
Correct |
9 ms |
7372 KB |
Output is correct |
15 |
Correct |
9 ms |
7244 KB |
Output is correct |
16 |
Correct |
7 ms |
7244 KB |
Output is correct |
17 |
Correct |
7 ms |
7252 KB |
Output is correct |
18 |
Correct |
6 ms |
7212 KB |
Output is correct |
19 |
Correct |
7 ms |
7244 KB |
Output is correct |
20 |
Correct |
7 ms |
7244 KB |
Output is correct |
21 |
Correct |
14 ms |
7372 KB |
Output is correct |
22 |
Correct |
92 ms |
7244 KB |
Output is correct |
23 |
Correct |
61 ms |
7208 KB |
Output is correct |
24 |
Correct |
71 ms |
7244 KB |
Output is correct |
25 |
Correct |
69 ms |
7244 KB |
Output is correct |
26 |
Correct |
59 ms |
7244 KB |
Output is correct |
27 |
Correct |
52 ms |
7244 KB |
Output is correct |
28 |
Correct |
53 ms |
7244 KB |
Output is correct |
29 |
Correct |
78 ms |
7244 KB |
Output is correct |
30 |
Correct |
70 ms |
7244 KB |
Output is correct |