Given  integers, each time one can perform the following operation: select the maximum interger  and the minimum integer  among them, and then replace both  and  with .

    Is it possible to make all integers equal after a finite number of operations? If yes, what's the final result?

输入描述:

    There are multiple test cases. The first line of the input contains an integer  (about 20) indicating the number of test cases. For each test case:
    The first line contains an integer  () indicating the number of integers.
    The second line contains  integers  () indicating the given integers.

输出描述:

    For each test case output one line. If it's possible to make all integers equal, output the integer they'll become; Otherwise output "Impossible" (without quotes).

2
3
1 2 3
2
5 5

2
5