#include <cstdio>

int n;
int ans;

int main(){
	scanf("%d", &n);
	for(int i=0; i*i<=n; ++i)
		ans = i*i;
	printf("%d\n", ans);
}
### Prompt

Please create a solution in Cpp to 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 <cstdio>

int n;
int ans;

int main(){
	scanf("%d", &n);
	for(int i=0; i*i<=n; ++i)
		ans = i*i;
	printf("%d\n", ans);
}
```