//20B (Div.-2)

#include<iostream>
#include<cstdlib>
#include<algorithm>
#include<cmath>
//#include<conio.h>
using namespace std;


void main()
{
	double a,b,c;
	cin>>a>>b>>c;
	if(a==0 && b==0)
		cout<<"-1"<<endl;
	else if((b*b-4*a*c)<0)
		cout<<"-1"<<endl;
	else if(a==0)
	{
		cout<<"1"<<endl;
		cout<<-(c/b);
	}
	else if(b*b==4*a*c)
	{
		cout<<"2"<<endl;
		cout<<-(b/2*a)<<endl;
		cout<<-(b/2*a)<<endl;
	}
	else
	{
		float r1=(-b+pow((b*b-4*a*c),0.5))/(2*a);
		float r2=(-b-pow((b*b-4*a*c),0.5))/(2*a);
		cout<<"2"<<endl;
		if(r1>r2)
			cout<<float(r2)<<endl<<float(r1)<<endl;
		if(r2>r1)
			cout<<float(r1)<<endl<<float(r2)<<endl;
	}
	//getch();
}