Function not working

This program should return the number of roots of a 2nd degree polynomial, but it always returns 2 roots, whatever coefficients I put.
What´s wrong??

It´s in spanish, so RAICES=ROOTS, and disc means the discriminant of the equation (b^2 - 4*a*c).

Thanks in advance.

Code:

---

#include <stdio.h>
#include <stdlib.h>

  int raices (int a, int b, int c)
    {
    int x,y,z,disc;
    disc=((y*y)-(4*x*z));
   
    if (disc<0)
        return 0;
    if(disc==0)
        return 1;
    if(disc>0)
        return 2;
   
    }

int main()
{       
  int a,b,c;
 
  printf("a= ");
  scanf("%d",&a);
  printf("b= ");
  scanf("%d",&b);
  printf("c= ");
  scanf("%d",&c);
  printf("El polinomio tiene %d raices\n",raices(a,b,c));
 
  system("PAUSE");       
  return 0;
}

---

> disc=((y*y)-(4*x*z));
Try it with a,b,c and not x,y,z

excellent!

Now I must think why it doesn´t work the other way...

thanks!!!!