Perfect Squares

Given an array a₁, a₂, ..., a_n 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, ..., a_n ( - 10⁶ ≤ a_i ≤ 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.

Example

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.

 

代码：

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cmath>
using namespace std;
int check(int t)
{
    if(t < 0)return 1;
    int i = 0;
    while(i <= t)
    {
        if(i * i == t)return 0;
        else if(i * i > t)return 1;
        i ++;
    }
}
int main()
{
    int n,m = -100000000;
    cin>>n;
    int d;
    for(int i = 0;i < n;i ++)
    {
        cin>>d;
        if(d > m && check(d))m = d;
    }
    cout<<m;
}