java progrme for quadratic equation to find roots

import java.util.*;
class Abc
{
public static void main(String args[])
{

Scanner s=new Scanner(System.in);
float a,b,c,d;
float r1,r2;
System.out.println("enter equation numbers");
a=s.nextInt();
b=s.nextInt();
c=s.nextInt();
d=(b*b)-(4*a*c);
if(d<0)
{
System.out.println("roots are imaginary");
}
else if(d==0)
{
r1=(float)(-b+Math.sqrt(d))/(2*a);
r2=(float)(-b-Math.sqrt(d))/(2*a);
System.out.println(r1+" "+r2);
}
else
{
r1=r2=-b/(2*a);
System.out.println(r1);
}
}
}