#include using namespace std; int main() { long long a,b,c; scanf("%lld%lld%lld",&a,&b,&c); if(a==0) { if(b==0) puts(c?"0":"-1"); else printf("1\n%.15f\n",-c*1.0/b); } else { if(a<0)a=-a,b=-b,c=-c; long double d=b*b-4.0*a*c; if(fabs(d)<1e-12) printf("1\n%.15lf\n",-b/2.0/a); else if(d<0) puts("0"); else { double x,y; if(b>0) { x=(-b-sqrt(d))/2/a; y=c*1.0/a/x; } else { y=(-b+sqrt(d))/2/a; x=c*1.0/a/y; } printf("2\n%.15lf\n%.15lf\n",x,y); } } return 0; }