#include<bits/stdc++.h>
using namespace std;
#define int long long
#define ff first
#define ss second
#define pb push_back
const int N=355;
int dp[N][N][2];
const int mod=1e9+7;
int arr[N];
int mult[N];
int modd(int a){
return((a%mod+mod)%mod);
}
int fun(int a, int b){
int ans=1;
for(int i=0;i<=31;i++){
if(b&(1<<i)){
ans=modd((ans*a));
}
a=modd(a*a);
}
return ans;
}
int find(int a, int b){
if(a==b)return 1;
if(a==0 or b==0)return 1;
int p=(arr[b]%mod*(arr[a-b]%mod))%mod;
return arr[a]%mod*fun(p,mod-2)%mod;
}
signed main(){
arr[0]=1;
for(int i=1;i<N;i++){
arr[i]=arr[i-1]*i%mod;
}
for(int i=0;i<N;i++){
mult[i]=fun(i,mod-2);
}
int n;
cin>>n;
dp[0][0][0]=1;
for(int i=1;i<=n;i++){
for(int j=0;j<=n;j++){
for(int k=0;k<=n;k++){
if(j+k>n)break;
if(k==i){
dp[i][j+k][1]+=(dp[i-1][j][1]+dp[i-1][j][0])*find(n-j,k);
}
else{
dp[i][j+k][1]+=dp[i-1][j][1]*find(n-j,k);
dp[i][j+k][0]+=dp[i-1][j][0]*find(n-j,k);
}
dp[i][j+k][1]%=mod;
dp[i][j+k][0]%=mod;
}
}
}
cout<<dp[n][n][1];
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
336 KB |
Output is correct |
2 |
Correct |
1 ms |
336 KB |
Output is correct |
3 |
Correct |
1 ms |
336 KB |
Output is correct |
4 |
Correct |
1 ms |
336 KB |
Output is correct |
5 |
Correct |
1 ms |
504 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
336 KB |
Output is correct |
2 |
Correct |
1 ms |
336 KB |
Output is correct |
3 |
Correct |
1 ms |
336 KB |
Output is correct |
4 |
Correct |
1 ms |
336 KB |
Output is correct |
5 |
Correct |
1 ms |
504 KB |
Output is correct |
6 |
Correct |
1 ms |
336 KB |
Output is correct |
7 |
Correct |
1 ms |
336 KB |
Output is correct |
8 |
Correct |
1 ms |
336 KB |
Output is correct |
9 |
Correct |
2 ms |
508 KB |
Output is correct |
10 |
Correct |
1 ms |
336 KB |
Output is correct |
11 |
Correct |
2 ms |
336 KB |
Output is correct |
12 |
Correct |
3 ms |
336 KB |
Output is correct |
13 |
Correct |
2 ms |
504 KB |
Output is correct |
14 |
Correct |
3 ms |
336 KB |
Output is correct |
15 |
Correct |
3 ms |
336 KB |
Output is correct |
16 |
Correct |
4 ms |
504 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
336 KB |
Output is correct |
2 |
Correct |
1 ms |
336 KB |
Output is correct |
3 |
Correct |
1 ms |
336 KB |
Output is correct |
4 |
Correct |
1 ms |
336 KB |
Output is correct |
5 |
Correct |
1 ms |
504 KB |
Output is correct |
6 |
Correct |
1 ms |
336 KB |
Output is correct |
7 |
Correct |
1 ms |
336 KB |
Output is correct |
8 |
Correct |
1 ms |
336 KB |
Output is correct |
9 |
Correct |
2 ms |
508 KB |
Output is correct |
10 |
Correct |
1 ms |
336 KB |
Output is correct |
11 |
Correct |
2 ms |
336 KB |
Output is correct |
12 |
Correct |
3 ms |
336 KB |
Output is correct |
13 |
Correct |
2 ms |
504 KB |
Output is correct |
14 |
Correct |
3 ms |
336 KB |
Output is correct |
15 |
Correct |
3 ms |
336 KB |
Output is correct |
16 |
Correct |
4 ms |
504 KB |
Output is correct |
17 |
Execution timed out |
1048 ms |
840 KB |
Time limit exceeded |
18 |
Halted |
0 ms |
0 KB |
- |