Given an array a1, a2, ..., an 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, ..., an ( - 106 ≤ ai ≤ 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.

Examples

Input

2
4 2


Output

2


Input

8
1 2 4 8 16 32 64 576


Output

32

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.
import java.util.*;
import java.io.*;
public class CF914A
{
   public static void main(String[] args)
   {
      TomScanner sc = new TomScanner(System.in);
      int x =sc.nextInt();
      int[] nums = new int[x];
		for(int k=0; k<x; k++)
			nums[k]=sc.nextInt();
		int max = Integer.MIN_VALUE;
		for(int z:nums)
		{
			if(z>=0){
				int sqrt = (int)(Math.sqrt(z));
				if(sqrt*sqrt!=z)
					max=Math.max(max,z);
			}
			else if(z<=0)
				max=Math.max(max,z);
		}
		System.out.println(max);
   }
}
class TomScanner
{
   BufferedReader	br;
   StringTokenizer st;
      
   public TomScanner(String fileNameIn)
   {
      try{
         FileReader fr = new FileReader(fileNameIn);
         br	= new	BufferedReader(fr);
      }
      catch(Exception e){System.out.println("Read Error");}
   }
   public TomScanner(InputStream is)
   {
      br = new BufferedReader(new InputStreamReader(is));
   }
   public static StringTokenizer	getst(BufferedReader	br) throws Exception{
      return new StringTokenizer(br.readLine(),	" ");
   }
   public String next()
   {
      try{
         return st.nextToken();
      }
      catch(Exception e){
         try{
            st = getst(br);
            return st.nextToken();
         }
         catch(Exception e2){
            return null;}
      }
   }
   public long nextLong(){
      return Long.parseLong(next());
   }
   public int nextInt(){
      return Integer.parseInt(next());
   }
}