#include <cstdio>
 
int main() {
  int i, N;
 
  scanf("%d", &N);
 
  for (i = 1; i * i <= N; i++);
 
  printf("%d\n", (i - 1) * (i - 1));
}
### 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 main() {
  int i, N;
 
  scanf("%d", &N);
 
  for (i = 1; i * i <= N; i++);
 
  printf("%d\n", (i - 1) * (i - 1));
}
```