#include<stdio.h>
#include<cmath>

int N;

int main(){
    scanf("%d", &N);

    printf("%d", int(sqrt(N))*int(sqrt(N)));

    return 0;
}
### Prompt

Your task is to create a cpp solution 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<stdio.h>
#include<cmath>

int N;

int main(){
    scanf("%d", &N);

    printf("%d", int(sqrt(N))*int(sqrt(N)));

    return 0;
}
```