#include <bits/stdc++.h>
using namespace std;
int main(){
int t;cin>>t;
z:while(t--){
int n;cin>>n;
int arr[n+1],pos[n+1];
for(int i = 1;i<=n;i++){
cin>>arr[i];pos[arr[i]] = i;
}
int g = 0;
for(int i = 1;i<=n/2;i++){
if(arr[i]!=i)g++;
if(n-arr[i]+1!=arr[n-i+1]){
cout<<-1<<endl;
goto z;
}
}
int e = 0;
for(int i = 1;i<=n;i++){
int x = pos[i];
if(arr[i]==i)continue;
if(arr[n-i+1]==n-x+1&&arr[n-x+1]==n-i+1&&arr[x]==i){
e++;
}
}
cout<<g-(e/4)<<" "<<0<<endl;
}
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
8 ms |
348 KB |
Wrong answer |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
28 ms |
348 KB |
Correctly distinguished between possibility and impossibility |
2 |
Correct |
29 ms |
860 KB |
Correctly distinguished between possibility and impossibility |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
8 ms |
348 KB |
Wrong answer |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
28 ms |
348 KB |
Correctly distinguished between possibility and impossibility |
2 |
Correct |
29 ms |
860 KB |
Correctly distinguished between possibility and impossibility |
3 |
Correct |
543 ms |
16292 KB |
Correctly distinguished between possibility and impossibility |
4 |
Correct |
529 ms |
16212 KB |
Correctly distinguished between possibility and impossibility |
5 |
Correct |
548 ms |
16208 KB |
Correctly distinguished between possibility and impossibility |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
8 ms |
348 KB |
Wrong answer |
2 |
Halted |
0 ms |
0 KB |
- |