DMOPC '21 Contest 5 P4 - Permutations & Primes
View as PDFGiven an integer , find any permutation 
 of 
 that satisfies the following, or report that no such permutation exists:
- For all 
,
is prime.
 - The number of distinct 
as
is the minimum possible among all permutations satisfying the first condition.
 
Note that there is no absolute value in the second condition.
To ensure the integrity of your solution, there may be up to  test cases.
Constraints
The sum of  over all test cases does not exceed 
.
Subtask 1 [20%]
 is a multiple of 
.
Subtask 2 [40%]
 is even.
Subtask 3 [40%]
No additional constraints.
Input Specification
The first line contains an integer .
The next  lines each contain a single integer 
, describing one test case.
Output Specification
For each test case, if no such permutation exists, output  on a line by itself. Otherwise, output 
 space-separated integers 
, a permutation that satisfies the conditions.
Sample Input
2
4
3
Sample Output
3 1 4 2
-1
Explanation
For the first test case, , 
, and 
 are all primes, and there are 
 distinct numbers among 
, 
, and 
.
For the second test case, it is not possible for all adjacent absolute differences to be prime.
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