roots of a quadratic quadratic equation

/* write a C program to find and output all the roots of a *
* quadratic equation, for non-zero coefficients. In case *
* of errors your program should report suitable error message*/

#include stdio.h
#include conio.h
#include stdlib.h
#include math.h

void main()
{
float A, B, C, root1, root2;
float realp, imagp, disc;

clrscr();

printf("Enter the values of A, B and C\n");
scanf("%f %f %f", &A,&B,&C);

/* If A = 0, it is not a quadratic equation */

if( A==0 || B==0 || C==0)
{
printf("Error: Roots cannot be determined\n");
exit(1);
}
else
{
disc = B*B - 4.0*A*C;
if(disc < 0)
{
printf("Imaginary Roots\n");
realp = -B/(2.0*A) ;
imagp = sqrt(abs(disc))/(2.0*A);
printf("Root1 = %f +i %f\n",realp, imagp);
printf("Root2 = %f -i %f\n",realp, imagp);
}
else if(disc == 0)
{
printf("Roots are real and equal\n");
root1 = -B/(2.0*A);
root2 = root1;
printf("Root1 = %f \n",root1);
printf("Root2 = %f \n",root2);
}
else if(disc > 0 )
{
printf("Roots are real and distinct\n");
root1 =(-B+sqrt(disc))/(2.0*A);
root2 =(-B-sqrt(disc))/(2.0*A);
printf("Root1 = %f \n",root1);
printf("Root2 = %f \n",root2);
}
}

} /* End of main() */

/*---------------------------
Output
RUN 1
Enter the values of A, B and C
3 2 1
Imaginary Roots
Root1 = -0.333333 +i 0.471405
Root2 = -0.333333 -i 0.471405

RUN 2
Enter the values of A, B and C
1 2 1
Roots are real and equal
Root1 = -1.000000
Root2 = -1.000000

RUN 3
Enter the values of A, B and C
3 5 2
Roots are real and distinct
Root1 = -0.666667
Root2 = -1.000000
---------------------------------*/

The important points to note in this program are the usage of stdlib and math header files. The use of latter is already mentioned. The first is used because here we have used a abs() funtion which takes the unsigned value of discriminent. The logic is straight. First we calculate discriminant of the equation and check if the roots are real. If they are real, then we calculate normal value, and if not we use the absolute value to calculate the imaginary roots