#include<iostream>
using namespace std;
int main()
{
	int n,sq=1,i=1;
	cin>>n;
	while(sq<=n)
	{
		sq=i*i;
		i++;
	}
	i=i-2;
	sq=i*i;
	cout<<sq;
}
### Prompt

Create a solution in CPP for the following problem:

Find the largest square number not exceeding N. Here, a square number is an integer that can be represented as the square of an integer.

Constraints

* 1 \leq N \leq 10^9
* N is an integer.

Input

Input is given from Standard Input in the following format:


N


Output

Print the largest square number not exceeding N.

Examples

Input

10


Output

9


Input

81


Output

81


Input

271828182


Output

271821169

### Response

```cpp
#include<iostream>
using namespace std;
int main()
{
	int n,sq=1,i=1;
	cin>>n;
	while(sq<=n)
	{
		sq=i*i;
		i++;
	}
	i=i-2;
	sq=i*i;
	cout<<sq;
}
```