Interesting number 
Time limit:  1.00 s 
Memory limit:  256 MB 

There are $n$ numbers written on a blackboard. Exactly one of the numbers is interesting because it is both prime and palindrome. Can you find it?
Input
The first input line contains an integer $t$: the number of test cases.
Each test case consists of two lines. The first line contains an integer $n$: the amount of numbers. The second line contains $n$ numbers on the blackboard.
Output
For each test case, output the interesting number.
Constraints
 $1 \le t \le 1000$
 each number is between $1$ and $1000$
 the sum of all $n$ values is at most $10^5$
Example
Input:
3
5
12 8 11 14 19
3
6 7 8
4
44 85 100 131
Output:
11
7
131