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.awt.BorderLayout;
import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Scanner;
import java.util.StringTokenizer;
import java.util.logging.Level;
import java.util.logging.Logger;

public class Main {

    public static void main(String[] args) {
        InputReader reader = new InputReader(System.in);
        int number = reader.nextInt();
        int[] myArray = new int[number];
        for (int i = 0; i < number; i++) {
            myArray[i] = reader.nextInt();
        }
        Arrays.sort(myArray);
        for (int i = myArray.length - 1; i >= 0; i--) {
            double square = Math.sqrt(myArray[i]);
            if (square != (int) square) {
                System.out.println(myArray[i]);
                break;
            }
        }
    }

    static class InputReader {

        StringTokenizer tokenizer;
        BufferedReader reader;
        String token;
        String temp;

        public InputReader(InputStream stream) {
            tokenizer = null;
            reader = new BufferedReader(new InputStreamReader(stream));
        }

        public InputReader(FileInputStream stream) {
            tokenizer = null;
            reader = new BufferedReader(new InputStreamReader(stream));
        }

        public String nextLine() throws IOException {
            return reader.readLine();
        }

        public String next() {
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    if (temp != null) {
                        tokenizer = new StringTokenizer(temp);
                        temp = null;
                    } else {
                        tokenizer = new StringTokenizer(reader.readLine());
                    }

                } catch (IOException e) {
                }
            }
            return tokenizer.nextToken();
        }

        public double nextDouble() {
            return Double.parseDouble(next());
        }

        public int nextInt() {
            return Integer.parseInt(next());
        }

        public long nextLong() {
            return Long.parseLong(next());
        }
    }
}
