Perfect Squares （水题）

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.

唯一需要注意的是给定的数有可能是负数，负数一定不是

coed：

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cmath>
#define INF 0x3f3f3f3f
using namespace std;
int main(){
    int n;
    int a[1010];
    scanf("%d",&n);
    int i;
    for(i = 0; i < n; i++){
        scanf("%d",&a[i]);
    }
    int ans = -INF;
    for(i = 0; i < n; i++){
        int tmp = (int)sqrt((double)a[i]);
        if(a[i]<0||tmp*tmp!=a[i]){
            ans = max(ans,a[i]);
        }
    }
    printf("%d\n",ans);
    return 0;
}