Given an array a1, a2, ..., a**n of n integers, find the largest number in the array that is not a perfect square.

A number x is said to be a perfect square if there exists an integer y such that x = y2.

Input

The first line contains a single integer n (1 ≤ n ≤ 1000) — the number of elements in the array.

The second line contains n integers a1, a2, ..., a**n ( - 106 ≤ a**i ≤ 106) — the elements of the array.

It is guaranteed that at least one element of the array is not a perfect square.

Output

Print the largest number in the array which is not a perfect square. It is guaranteed that an answer always exists.

Note

In the first sample case, 4 is a perfect square, so the largest number in the array that is not a perfect square is 2.

Samples

2
4 2

2

8
1 2 4 8 16 32 64 576

32