#include <bits/stdc++.h>
std::set<int, std::greater<int> > s;
int n, k;
int main() {
  scanf("%d", &n);
  while (n--) {
    scanf("%d", &k);
    s.insert(k);
  }
  for (std::set<int>::iterator it = s.begin(); it != s.end(); it++) {
    if (pow(int(sqrt(*it)), 2) != *it) {
      printf("%d ", *it);
      return 0;
    }
  }
  return 0;
}

### Prompt

In Cpp, your task is to solve the following problem:

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.

### Response

```cpp
#include <bits/stdc++.h>
std::set<int, std::greater<int> > s;
int n, k;
int main() {
  scanf("%d", &n);
  while (n--) {
    scanf("%d", &k);
    s.insert(k);
  }
  for (std::set<int>::iterator it = s.begin(); it != s.end(); it++) {
    if (pow(int(sqrt(*it)), 2) != *it) {
      printf("%d ", *it);
      return 0;
    }
  }
  return 0;
}

```