#include <bits/stdc++.h>
using namespace std;
int main(){
    int a,b,c;
    cin>>a>>b>>c;
    if(a==0){
        if(b==0){
            if(c==0){
                cout<<-1;
            }else{
                cout<<0;
            }
        }else{
            cout<<1<<endl<<(double)(c)/(double)(b);
        }
    }else{
        int D=b*b-4*a*c;
        if(D>0)cout<<0;
        else if(D=0)cout<<1<<endl<<-(double)(b)/(double)(a)*2;
        else cout<<2<<endl<<(-(double)(b)-sqrt(D))/(double)(a)*2<<endl<<(-(double)(b)+sqrt(D))/(double)(a)*2;
    }
}