#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
#define rep(i,n) for(int i=0;i<n;i++)
#define cinf(n,x) for(int i=0;i<(n);i++)cin>>x[i];
#define ft first
#define sc second
#define pb push_back
#define lb lower_bound
#define ub upper_bound
#define all(v) (v).begin(),(v).end()
#define mod 1000000007
using namespace std;
typedef long long ll;
template<class T> using V=vector<T>;
using Graph = vector<vector<int>>;
using P=pair<ll,ll>;
typedef unsigned long long ull;
typedef long double ldouble;
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; }
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; }

const ll INF=1e18;

int main(){
    ll a,b,c;
    cin>>a>>b>>c;
    bool ok=1;
    set<double> x;
    if(a==0){
        if(b==0){
            if(c==0){
                ok=0;
            }
        }else{
            x.insert((double)-c/b);
        }
    }else{
        if(b*b-4*a*c>=0){
            ll d=b*b-4*a*c;
            if(d==0){
                x.insert((double)-b/(2*a));
            }else{
                x.insert((double)(-b+sqrt(d))/(2*a));
                x.insert((double)(-b-sqrt(d))/(2*a));
            }
        }
    }
    if(ok){
        cout<<x.size()<<endl;
        if(x.size()>0){
            while(!x.empty()){
                double xx=*begin(x);
                cout<<fixed<<setprecision(15)<<xx<<endl;
                x.erase(xx);
            }
        }
    }else cout<<-1<<endl;
}