Problem:
Score : 200 points

Problem Statement

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.

Sample Input 1

10

Sample Output 1

9

10 is not square, but 9 = 3 × 3 is. Thus, we print 9.

Sample Input 2

81

Sample Output 2

81

Sample Input 3

271828182

Sample Output 3

271821169

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.util.Scanner;

public class Main
{
    public static void main(String args[])
    {
        Scanner sc = new Scanner(System.in);

        int n = sc.nextInt();

        for(int i = n; i > 0; i--) {
            int sq = (int)Math.sqrt(i);
            if(i == sq * sq) {
                n = i;
                break;
            }
        }

        System.out.println(n);
    }
}