#include <bits/stdc++.h>
typedef long long ll;
using namespace std;
const int MOD = 1e9+7;
ll dp[102][102][3][1002], a[102];
inline void add(ll &x, ll y){
x += y;
if (x>=MOD) x -= MOD;
}
int main(){
int n, L;
scanf("%d %d", &n, &L);
for (int i=1;i<=n;i++) scanf("%lld", a+i);
if (n==1) {printf("1\n"); return 0;}
sort(a+1, a+n+1);
dp[n-1][0][1][(a[n]-a[n-1])] = 1;
if (a[n]-a[n-1]*2<=L) dp[n-1][0][2][(a[n]-a[n-1])*2] = 1;
for (int i=n-2;i;i--){
for (int j=0;j<=n;j++){
int val0 = (a[i+1] - a[i]) * (j*2);
int val1 = (a[i+1] - a[i]) * (j*2 + 1);
int val2 = (a[i+1] - a[i]) * (j*2 + 2);
if (j){
for (int k=val0;k<=L;k++){
add(dp[i][j][0][k], dp[i+1][j+1][0][k-val0] * (j+1) %MOD);
add(dp[i][j][0][k], dp[i+1][j][0][k-val0] * (j*2) %MOD);
add(dp[i][j][0][k], dp[i+1][j-1][0][k-val0] * (j-1) %MOD);
add(dp[i][j][0][k], dp[i+1][j][1][k-val0] *2 %MOD);
add(dp[i][j][0][k], dp[i+1][j-1][1][k-val0] *2 %MOD);
}}
for (int k=val1;k<=L;k++){
add(dp[i][j][1][k], dp[i+1][j+1][1][k-val1] * (j+1) %MOD);
add(dp[i][j][1][k], dp[i+1][j][1][k-val1] * (j*2+1) %MOD);
if (j) add(dp[i][j][1][k], dp[i+1][j-1][1][k-val1] * j %MOD);
add(dp[i][j][1][k], dp[i+1][j][2][k-val1]);
if (j) add(dp[i][j][1][k], dp[i+1][j-1][2][k-val1]);
}
for (int k=val2;k<=L;k++){
add(dp[i][j][2][k], dp[i+1][j+1][2][k-val2] * (j+1) %MOD);
add(dp[i][j][2][k], dp[i+1][j][2][k-val2] * (j*2+2) %MOD);
if (j) add(dp[i][j][2][k], dp[i+1][j-1][2][k-val2] * (j+1) %MOD);
}
}
}
ll ans = 0;
for (int k=0;k<=L;k++){
add(ans, dp[1][1][0][k]);
add(ans, dp[1][0][1][k]*2%MOD);
//if (k<=10) printf("%d %d\n", dp[1][1][0][k], dp[1][0][1][k]);
}
printf("%lld\n", ans);
return 0;
}
Compilation message
skyscraper.cpp: In function 'int main()':
skyscraper.cpp:15:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
15 | scanf("%d %d", &n, &L);
| ~~~~~^~~~~~~~~~~~~~~~~
skyscraper.cpp:16:33: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
16 | for (int i=1;i<=n;i++) scanf("%lld", a+i);
| ~~~~~^~~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Correct |
1 ms |
204 KB |
Output is correct |
3 |
Correct |
0 ms |
332 KB |
Output is correct |
4 |
Correct |
1 ms |
460 KB |
Output is correct |
5 |
Correct |
2 ms |
844 KB |
Output is correct |
6 |
Correct |
1 ms |
972 KB |
Output is correct |
7 |
Correct |
1 ms |
588 KB |
Output is correct |
8 |
Correct |
1 ms |
972 KB |
Output is correct |
9 |
Correct |
1 ms |
972 KB |
Output is correct |
10 |
Correct |
1 ms |
844 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
1996 KB |
Output is correct |
2 |
Correct |
2 ms |
1740 KB |
Output is correct |
3 |
Correct |
2 ms |
2380 KB |
Output is correct |
4 |
Correct |
1 ms |
1808 KB |
Output is correct |
5 |
Correct |
2 ms |
1868 KB |
Output is correct |
6 |
Correct |
2 ms |
2124 KB |
Output is correct |
7 |
Correct |
1 ms |
1612 KB |
Output is correct |
8 |
Correct |
2 ms |
2380 KB |
Output is correct |
9 |
Correct |
2 ms |
2508 KB |
Output is correct |
10 |
Correct |
1 ms |
1868 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Correct |
1 ms |
204 KB |
Output is correct |
3 |
Correct |
0 ms |
332 KB |
Output is correct |
4 |
Correct |
1 ms |
460 KB |
Output is correct |
5 |
Correct |
2 ms |
844 KB |
Output is correct |
6 |
Correct |
1 ms |
972 KB |
Output is correct |
7 |
Correct |
1 ms |
588 KB |
Output is correct |
8 |
Correct |
1 ms |
972 KB |
Output is correct |
9 |
Correct |
1 ms |
972 KB |
Output is correct |
10 |
Correct |
1 ms |
844 KB |
Output is correct |
11 |
Correct |
1 ms |
1996 KB |
Output is correct |
12 |
Correct |
2 ms |
1740 KB |
Output is correct |
13 |
Correct |
2 ms |
2380 KB |
Output is correct |
14 |
Correct |
1 ms |
1808 KB |
Output is correct |
15 |
Correct |
2 ms |
1868 KB |
Output is correct |
16 |
Correct |
2 ms |
2124 KB |
Output is correct |
17 |
Correct |
1 ms |
1612 KB |
Output is correct |
18 |
Correct |
2 ms |
2380 KB |
Output is correct |
19 |
Correct |
2 ms |
2508 KB |
Output is correct |
20 |
Correct |
1 ms |
1868 KB |
Output is correct |
21 |
Correct |
7 ms |
9548 KB |
Output is correct |
22 |
Correct |
226 ms |
141068 KB |
Output is correct |
23 |
Correct |
188 ms |
142716 KB |
Output is correct |
24 |
Correct |
191 ms |
168076 KB |
Output is correct |
25 |
Correct |
205 ms |
145284 KB |
Output is correct |
26 |
Correct |
175 ms |
144680 KB |
Output is correct |
27 |
Correct |
121 ms |
152304 KB |
Output is correct |
28 |
Correct |
155 ms |
165208 KB |
Output is correct |
29 |
Correct |
228 ms |
197812 KB |
Output is correct |
30 |
Correct |
193 ms |
144476 KB |
Output is correct |