#include <math.h>
int masodfoku(double a, double b, double c, double *x1, double *x2)
{
 double d;
 if ( (a!=0) && (d = ((b*b)-4*a*c) )>=0 )
 {
      *x1 = (-1*b+sqrt(d))/(a*2) ;
      *x2 = (-1*b-sqrt(d))/(a*2) ;
      return 1;
} else if (a==0 && b!=0)
         {
             *x1=*x2=(-1*c)/b;
             return 1;
             } else if (a==0 && b==0 && c==0)
             {*x1=*x2=0; return 1;}
              else return 0;
}