#include<bits/stdc++.h>
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;
}