#include<stdio.h>
#include<math.h>
int main()
{
	long long x;
	scanf("%lld",&x);
	x=sqrt(x);
	x=x*x;
	printf("%lld\n",x);
	return 0;
 } 
### 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<stdio.h>
#include<math.h>
int main()
{
	long long x;
	scanf("%lld",&x);
	x=sqrt(x);
	x=x*x;
	printf("%lld\n",x);
	return 0;
 } 
```