#include<bits/stdc++.h>
using namespace std;
//#pragma GCC optimize("O3,unroll-loops")
//#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#define rep(i, x, y) for(int i = x; i <= y; ++i)
#define repi(i,x,y) for(int i = x; i >= y; --i)
#define ci(x) int x; cin>> x
#define TC(t) ci(t); while(t--)
#define fi first
#define se second
#define pb push_back
#define all(x) x.begin(), x.end()
#define cii(x, y) ci(x); ci(y)
#define ciii(x, y, z) ci(x); ci(y); ci(z)
#define mp make_pair
//#define int long long
typedef long long ll;
typedef vector<int> vi;
const int N = 1e2 + 5;
const int NN = 16 + 15;
const int mod = 1e9+7;
const int mod1 = 1e9 + 9;
const int pi = 31;
const ll inf = 1e15 + 6;
const int block = 500;
const int dx[4] = {-1, 0, 1, 0};
const int dy[4] = {0, -1, 0, 1};
void readfile(){
#ifdef ONLINE_JUDGE
#else
freopen("text.inp", "r", stdin);
#endif // ONLINE_JUDGE
// freopen("text.inp", "r", stdin);
// freopen("template.out", "w", stdout);
}
int n, L;
int a[N], S[N];
void inp(){
cin >> n >> L;
for(int i = 1; i <= n; ++i) cin >> a[i];
sort(a + 1, a + n + 1);
for(int i = n; i >= 1; --i) S[i] = S[i + 1] + a[i];
}
int add(int x, int y){
x += y;
while(x < 0) x += mod;
while(x >= mod) x -= mod;
return x;
}
int mul(int x, int y){
return (x * 1LL * y) % mod;
}
map<int,int> f[N][N][3];
set<int> s[N][N][3];
void process(){
f[1][1][0][-2*a[1]] = 1;
f[1][1][1][-a[1]] = 2;
f[1][1][2][0] = 1;
s[1][1][0].insert(-2*a[1]);
s[1][1][1].insert(-a[1]);
s[1][1][2].insert(0);
for(int i = 1; i < n; ++i){
for(int j = 1; j <= i; ++j){
for(int t = 0; t <= 2; ++t){
for(int sum : s[i][j][t]){
if(j >= 2){
// merge two cc
f[i + 1][j - 1][t][sum + 2*a[i + 1]] = add(f[i + 1][j - 1][t][sum + 2*a[i + 1]], mul(f[i][j][t][sum], j - 1));
s[i + 1][j - 1][t].insert(sum + 2*a[i + 1]);
}
if(t==0){ // not having any at the end or beginning
// new cc
if(sum - 2*a[i + 1] + S[i + 2] > 0 && sum - 2*a[i + 1] + 2*S[i + 2] <= L){
f[i + 1][j + 1][0][sum + -2*a[i + 1]] = add(f[i + 1][j + 1][0][sum + -2*a[i + 1]], mul(f[i][j][t][sum], j + 1));
s[i + 1][j + 1][0].insert(sum - 2*a[i + 1]);
}
if(sum - a[i + 1] + S[i + 2] > 0 && sum - a[i + 1] + 2*S[i + 2] <= L){
f[i + 1][j + 1][1][sum + -a[i + 1]] = add(f[i + 1][j + 1][1][sum + -a[i + 1]], mul(f[i][j][t][sum], 2)); // new cc but at the end or beginning
s[i + 1][j + 1][1].insert(sum - a[i + 1]);
}
// attach to existing cc
f[i + 1][j][0][sum] = add(f[i + 1][j][0][sum], mul(f[i][j][t][sum], 2*j));
s[i + 1][j][0].insert(sum);
f[i + 1][j][1][sum + a[i + 1]] = add(f[i + 1][j][1][sum + a[i + 1]], mul(f[i][j][t][sum], 2)); // increasing one endpoint
s[i + 1][j][1].insert(sum + a[i + 1]);
}
else if(t==1){
// new cc
if(sum - 2*a[i + 1] + S[i + 2] > 0 && sum - 2*a[i + 1] + 2*S[i + 2] <= L){
f[i + 1][j + 1][1][sum -2*a[i + 1]] = add(f[i + 1][j + 1][1][sum - 2*a[i + 1]], mul(f[i][j][t][sum], j));
s[i + 1][j + 1][1].insert(sum - 2*a[i + 1]);
}
if(sum - a[i + 1] + S[i + 2] > 0 && sum - a[i + 1] + 2*S[i + 2] <= L){
f[i + 1][j + 1][2][sum - a[i + 1]] = add(f[i + 1][j + 1][2][sum - a[i + 1]], f[i][j][t][sum]); // new cc but at one endpoint
s[i + 1][j + 1][2].insert(sum - a[i + 1]);
}
// attach to existing cc
f[i + 1][j][1][sum] = add(f[i + 1][j][1][sum], mul(f[i][j][t][sum], 2*j - 1));
f[i + 1][j][2][sum + a[i + 1]] = add(f[i + 1][j][2][sum + a[i + 1]], f[i][j][t][sum]); // increasing one endpoint to two endpoints
s[i + 1][j][1].insert(sum);
s[i + 1][j][2].insert(sum + a[i + 1]);
}
else{
if(j >= 2){
// new cc
if(sum - 2*a[i + 1] + S[i + 2] > 0 && sum - 2*a[i + 1] + 2*S[i + 2] <= L){
f[i + 1][j + 1][2][sum - 2*a[i + 1]] = add(f[i + 1][j + 1][2][sum - 2*a[i + 1]], mul(f[i][j][t][sum], j - 1));
s[i + 1][j + 1][2].insert(sum - 2*a[i + 1]);
}
// attach to existing cc
f[i + 1][j][2][sum] = add(f[i + 1][j][2][sum], mul(f[i][j][t][sum], 2*j - 2));
s[i + 1][j][2].insert(sum);
}
}
}
}
}
}
int res = 0;
for(int i = 0; i <= L; ++i)
res = add(res, f[n][1][2][i]);
cout << res;
}
int main() {
// readfile();
ios_base::sync_with_stdio(0);
cin.tie(0);
inp();
process();
return 0;
}
Compilation message
skyscraper.cpp: In function 'void readfile()':
skyscraper.cpp:33:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
33 | freopen("text.inp", "r", stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
2 ms |
3404 KB |
Output is correct |
| 2 |
Correct |
2 ms |
3404 KB |
Output is correct |
| 3 |
Correct |
2 ms |
3404 KB |
Output is correct |
| 4 |
Incorrect |
2 ms |
3316 KB |
Output isn't correct |
| 5 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
3404 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
2 ms |
3404 KB |
Output is correct |
| 2 |
Correct |
2 ms |
3404 KB |
Output is correct |
| 3 |
Correct |
2 ms |
3404 KB |
Output is correct |
| 4 |
Incorrect |
2 ms |
3316 KB |
Output isn't correct |
| 5 |
Halted |
0 ms |
0 KB |
- |
