We guessed some integer number x. You are given a list of almost all its divisors. Almost all means that there are all divisors except 1 and x in the list.
Your task is to find the minimum possible integer x that can be the guessed number, or say that the input data is contradictory and it is impossible to find such number.
You have to answer t independent queries.
The first line of the input contains one integer t (1 ≤ t ≤ 25) — the number of queries. Then t queries follow.
The first line of the query contains one integer n (1 ≤ n ≤ 300) — the number of divisors in the list.
The second line of the query contains n integers d_1, d_2, ..., d_n (2 ≤ d_i ≤ 10^6), where d_i is the i-th divisor of the guessed number. It is guaranteed that all values d_i are distinct.
For each query print the answer to it.
If the input data in the query is contradictory and it is impossible to find such number x that the given list of divisors is the list of almost all its divisors, print -1. Otherwise print the minimum possible x.
2 8 8 2 12 6 4 24 16 3 1 2
48 4