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.io.*;
import java.util.StringTokenizer;

public class Main {

    void solve(FastScanner in, PrintWriter out) throws IOException {
        int n = in.nextInt();
        int max = Integer.MIN_VALUE;
        for (int i = 0; i < n; i++) {
            int a = in.nextInt();
            if (a >= 0) {
                if ((int) Math.sqrt(1.0*a) != Math.sqrt(1.0*a)) {
                    if (a > max) {
                        max = a;
                    }
                }
            } else {
                if (a > max) {
                    max = a;
                }
            }
        }
        out.println(max);
        out.close();
    }

    public static void main(String[] args) throws IOException {
//        FastScanner in = new FastScanner(new FileReader("input.txt"));
//        PrintWriter out = new PrintWriter(new FileWriter("output.txt"));
        FastScanner in = new FastScanner(System.in);
        PrintWriter out = new PrintWriter(System.out);
        new Main().solve(in, out);
    }

    static class FastScanner {
        StringTokenizer st;
        BufferedReader br;

        public FastScanner(InputStream s) {
            br = new BufferedReader(new InputStreamReader(s));
        }

        public FastScanner(FileReader f) {
            br = new BufferedReader(f);
        }

        public String next() {
            while (st == null || !st.hasMoreTokens())
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (Exception e) { }
            return st.nextToken();
        }

        public String nextLine() {
            String str = "";
            try {
                str = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        }

        public boolean hasNext() {
            return st.hasMoreElements();
        }

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

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

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

        public boolean nextBoolean() {
            return Boolean.parseBoolean(next());
        }

        public void close() throws IOException {
            br.close();
        }
    }
}