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.
#include <bits/stdc++.h>
int main() {
  int cmpfunc(const void* a, const void* b);
  int n, a[1000], i, c, d;
  while (scanf("%d", &n) == 1) {
    for (i = 0; i < n; i++) {
      scanf("%d", &a[i]);
    }
    qsort(a, n, sizeof(int), cmpfunc);
    for (i = n - 1; i >= 0; i--) {
      c = a[i];
      d = sqrt(c);
      if (d * d != c) break;
    }
    printf("%d\n", c);
  }
  return 0;
}
int cmpfunc(const void* a, const void* b) { return (*(int*)a - *(int*)b); }
