#include<bits/stdc++.h>
using namespace std;
#define N 105
#define L 1005
const int mod = 1e9+7;
int n,l,a[N],dp[N][N][L][3],ans=0;
int add(int a,int b){
return ((a % mod)+(b % mod)) % mod;
}
int mul(int a,int b){
return ((long long)(a * b)) % mod;
}
int main(){
scanf("%d%d",&n,&l);
for(int i=1;i<=n;i++) scanf("%d",&a[i]);
sort(a+1,a+n+1);
if(n == 1){ // special case
printf("1");
return 0;
}
dp[1][1][0][0] = 1;
dp[1][1][0][1] = 2;
for(int idx=1;idx<n;idx++){
for(int comp=1;comp<=idx;comp++){
for(int sum=0;sum<=l;sum++){
for(int ex=0;ex<=2;ex++){ // ex is number of endpoint(begin/end) which was filled
int n_sum = sum + (2 * comp - ex) * (a[idx+1] - a[idx]); // add a[idx+1] to every available spaces
int val = dp[idx][comp][sum][ex];
if(n_sum > l) continue;
if(ex < 2){
// add idx+1 to endpoint and merge to some components
dp[idx+1][comp][n_sum][ex+1] = add(dp[idx+1][comp][n_sum][ex+1], mul((2 - ex), val));
// add idx+1 to endpoint and create new component
dp[idx+1][comp+1][n_sum][ex+1] = add(dp[idx+1][comp+1][n_sum][ex+1], mul((2 - ex), val));
}
// create new component
dp[idx+1][comp+1][n_sum][ex] = add(dp[idx+1][comp+1][n_sum][ex], mul((comp + 1 - ex), val));
// add to begin or end of component
dp[idx+1][comp][n_sum][ex] = add(dp[idx+1][comp][n_sum][ex], mul((2 * comp - ex), val));
// add and merge between two components
dp[idx+1][comp-1][n_sum][ex] = add(dp[idx+1][comp-1][n_sum][ex], mul((comp - 1), val));
}
}
}
}
for(int i=0;i<=l;i++) ans = add(ans, dp[n][1][i][2]);
printf("%d",ans);
}
Compilation message
skyscraper.cpp: In function 'int main()':
skyscraper.cpp:14:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
14 | scanf("%d%d",&n,&l);
| ~~~~~^~~~~~~~~~~~~~
skyscraper.cpp:15:29: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
15 | for(int i=1;i<=n;i++) scanf("%d",&a[i]);
| ~~~~~^~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
212 KB |
Output is correct |
2 |
Correct |
0 ms |
212 KB |
Output is correct |
3 |
Correct |
0 ms |
340 KB |
Output is correct |
4 |
Correct |
1 ms |
340 KB |
Output is correct |
5 |
Correct |
1 ms |
724 KB |
Output is correct |
6 |
Correct |
1 ms |
596 KB |
Output is correct |
7 |
Correct |
1 ms |
468 KB |
Output is correct |
8 |
Correct |
1 ms |
468 KB |
Output is correct |
9 |
Correct |
2 ms |
724 KB |
Output is correct |
10 |
Correct |
1 ms |
468 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
724 KB |
Output is correct |
2 |
Correct |
1 ms |
724 KB |
Output is correct |
3 |
Correct |
1 ms |
852 KB |
Output is correct |
4 |
Correct |
1 ms |
724 KB |
Output is correct |
5 |
Correct |
1 ms |
724 KB |
Output is correct |
6 |
Correct |
1 ms |
852 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 |
852 KB |
Output is correct |
10 |
Correct |
1 ms |
724 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
212 KB |
Output is correct |
2 |
Correct |
0 ms |
212 KB |
Output is correct |
3 |
Correct |
0 ms |
340 KB |
Output is correct |
4 |
Correct |
1 ms |
340 KB |
Output is correct |
5 |
Correct |
1 ms |
724 KB |
Output is correct |
6 |
Correct |
1 ms |
596 KB |
Output is correct |
7 |
Correct |
1 ms |
468 KB |
Output is correct |
8 |
Correct |
1 ms |
468 KB |
Output is correct |
9 |
Correct |
2 ms |
724 KB |
Output is correct |
10 |
Correct |
1 ms |
468 KB |
Output is correct |
11 |
Correct |
1 ms |
724 KB |
Output is correct |
12 |
Correct |
1 ms |
724 KB |
Output is correct |
13 |
Correct |
1 ms |
852 KB |
Output is correct |
14 |
Correct |
1 ms |
724 KB |
Output is correct |
15 |
Correct |
1 ms |
724 KB |
Output is correct |
16 |
Correct |
1 ms |
852 KB |
Output is correct |
17 |
Correct |
1 ms |
724 KB |
Output is correct |
18 |
Correct |
1 ms |
852 KB |
Output is correct |
19 |
Correct |
1 ms |
852 KB |
Output is correct |
20 |
Correct |
1 ms |
724 KB |
Output is correct |
21 |
Correct |
2 ms |
3156 KB |
Output is correct |
22 |
Incorrect |
128 ms |
37560 KB |
Output isn't correct |
23 |
Halted |
0 ms |
0 KB |
- |