#include <bits/stdc++.h>
//#pragma GCC optimize ("03")
#define FastIO ios_base::sync_with_stdio(false) , cin.tie(0) , cout.tie(0)
#define FILES freopen("in" , "r" , stdin) , freopen("out" , "w" , stdout)
#define ll long long
#define ull unsigned long long
#define ld long double
#define eb emplace_back
#define pb push_back
#define qwerty1 first
#define qwerty2 second
#define qwerty3 -> first
#define qwerty4 -> second
#define umap unordered_map
#define uset unordered_set
#define pii pair < ll , ll >
#define pq priority_queue
#define dbg(x) cerr << #x << ": " << x << '\n'
namespace FastRead
{
char __buff[5000];ll __lg = 0 , __p = 0;
char nc()
{
if(__lg == __p){__lg = fread(__buff , 1 , 5000 , stdin);__p = 0;if(!__lg) return EOF;}
return __buff[__p++];
}
template<class T>void read(T&__x)
{
T __sgn = 1; char __c;while(!isdigit(__c = nc()))if(__c == '-')__sgn = -1;
__x = __c - '0';while(isdigit(__c = nc()))__x = __x * 10 + __c - '0';__x *= __sgn;
}
}
using namespace FastRead;
using namespace std;
const ll N = 1e2 + 10;
const ll L = 4e3 + 10;
const ll M = 1e9 + 7;
const ld PI = acos(-1);
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
ll n , l;
ll a[N];
//array < array < array < ll , 4 > , 2 * L > , N > dp1 , dp_old;
ll curr_dp[N][2 * L][4] , old_dp[N][2 * L][4];
void add(ll &x , ll y)
{
y %= M;
x += y;
x %= M;
}
signed main()
{
// #ifndef ONLINE_JUDGE
// FastIO , FILES;
// #endif
ll i , j , s;
cin >> n >> l;
for(i = 1 ; i <= n ; i++)
cin >> a[i];
sort(a + 1 , a + n + 1);
old_dp[1][0 + L][0] = 1;
old_dp[1][-a[1] + L][1] = 1;
old_dp[1][-a[1] + L][2] = 1;
old_dp[1][-2 * a[1] + L][3] = 1;
for(i = 2 ; i <= n ; i++)
{
for(j = 1 ; j <= i ; j++)
{
for(s = -4 * l ; s <= 2 * l ; s++)
{
curr_dp[j][s][0] = curr_dp[j][s][1] = curr_dp[j][s][2] = curr_dp[j][s][3] = 0;
///merge
if(s - 2 * a[i] + L >= 0)
{
add(curr_dp[j][s + L][0] , 1ll * j * old_dp[j + 1][s - 2 * a[i] + L][0]);
add(curr_dp[j][s + L][1] , 1ll * j * old_dp[j + 1][s - 2 * a[i] + L][1]);
add(curr_dp[j][s + L][2] , 1ll * j * old_dp[j + 1][s - 2 * a[i] + L][2]);
add(curr_dp[j][s + L][3] , 1ll * j * old_dp[j + 1][s - 2 * a[i] + L][3]);
}
///concat
add(curr_dp[j][s + L][0] , 1ll * (2 * j - 2) * old_dp[j][s + L][0]);
add(curr_dp[j][s + L][1] , 1ll * (2 * j - 2) * old_dp[j][s + L][1]);
add(curr_dp[j][s + L][2] , 1ll * (2 * j - 2) * old_dp[j][s + L][2]);
add(curr_dp[j][s + L][3] , 1ll * (2 * j - 2) * old_dp[j][s + L][3]);
if(s - a[i] + L >= 0) add(curr_dp[j][s + L][0] , old_dp[j][s - a[i] + L][1]);
if(s - a[i] + L >= 0) add(curr_dp[j][s + L][2] , old_dp[j][s - a[i] + L][3]);
add(curr_dp[j][s + L][1] , old_dp[j][s + L][1]);
add(curr_dp[j][s + L][3] , old_dp[j][s + L][3]);
// add(curr_dp[j][s + L][3] , old_dp[j][s + L][1]);
if(s - a[i] + L >= 0) add(curr_dp[j][s + L][0] , old_dp[j][s - a[i] + L][2]);
add(curr_dp[j][s + L][2] , old_dp[j][s + L][2]);
add(curr_dp[j][s + L][3] , old_dp[j][s + L][3]);
if(s - a[i] + L >= 0) add(curr_dp[j][s + L][1] , old_dp[j][s - a[i] + L][3]);
// add(curr_dp[j][s + L][3] , old_dp[j][s + L][2]);
///new
if(j > 2 && s + 2 * a[i] + L < 2 * L)
{
add(curr_dp[j][s + L][0] , 1ll * (j - 2) * old_dp[j - 1][s + 2 * a[i] + L][0]);
add(curr_dp[j][s + L][1] , 1ll * (j - 2) * old_dp[j - 1][s + 2 * a[i] + L][1]);
add(curr_dp[j][s + L][2] , 1ll * (j - 2) * old_dp[j - 1][s + 2 * a[i] + L][2]);
add(curr_dp[j][s + L][3] , 1ll * (j - 2) * old_dp[j - 1][s + 2 * a[i] + L][3]);
}
if(s + a[i] + L < 2 * L) add(curr_dp[j][s + L][0] , old_dp[j - 1][s + a[i] + L][1]);
if(s + a[i] + L < 2 * L) add(curr_dp[j][s + L][0] , old_dp[j - 1][s + a[i] + L][2]);
if(s + 2 * a[i] + L < 2 * L) add(curr_dp[j][s + L][1] , old_dp[j - 1][s + 2 * a[i] + L][1]);
if(s + 2 * a[i] + L < 2 * L) add(curr_dp[j][s + L][2] , old_dp[j - 1][s + 2 * a[i] + L][2]);
if(s + 2 * a[i] + L < 2 * L) add(curr_dp[j][s + L][3] , old_dp[j - 1][s + 2 * a[i] + L][3]);
if(s + 2 * a[i] + L < 2 * L) add(curr_dp[j][s + L][3] , old_dp[j - 1][s + 2 * a[i] + L][3]);
if(s + a[i] + L < 2 * L) add(curr_dp[j][s + L][2] , old_dp[j - 1][s + a[i] + L][3]);
if(s + a[i] + L < 2 * L) add(curr_dp[j][s + L][1] , old_dp[j - 1][s + a[i] + L][3]);
}
}
swap(curr_dp , old_dp);
//memset(curr_dp , 0 , sizeof curr_dp);
}
ll ans = 0;
for(ll s = 0 ; s <= l ; s++)
add(ans , old_dp[1][s + L][0]);
cout << ans;
return 0;
}
Compilation message
skyscraper.cpp: In function 'int main()':
skyscraper.cpp:101:17: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
101 | if(s - a[i] + L >= 0) add(curr_dp[j][s + L][2] , old_dp[j][s - a[i] + L][3]);
| ^~
skyscraper.cpp:102:39: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
102 | add(curr_dp[j][s + L][1] , old_dp[j][s + L][1]);
| ^~~
skyscraper.cpp:106:17: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
106 | if(s - a[i] + L >= 0) add(curr_dp[j][s + L][0] , old_dp[j][s - a[i] + L][2]);
| ^~
skyscraper.cpp:107:39: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
107 | add(curr_dp[j][s + L][2] , old_dp[j][s + L][2]);
| ^~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
0 ms |
212 KB |
Output is correct |
| 2 |
Correct |
35 ms |
55472 KB |
Output is correct |
| 3 |
Incorrect |
39 ms |
55508 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
85 ms |
55532 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
0 ms |
212 KB |
Output is correct |
| 2 |
Correct |
35 ms |
55472 KB |
Output is correct |
| 3 |
Incorrect |
39 ms |
55508 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
