JAVA Help

import java.util.*;
class perfectsquare
{
    public static void main()
    {
        Scanner s=new Scanner(System.in);
        int n,i,c=0;
        System.out.println("enter a no.");
        n=s.nextInt();
        i=(int)Math.sqrt(n);
        if (i*i==n)
        System.out.println(n+"is perfect square");
        else
        System.out.println(n+"is not perfect square");
    }
}