#include <iostream>
#include <algorithm>
#include <vector>
#include <queue>
#include <cmath>
#include <functional>
#include <iomanip>

using namespace std;
using ll = long long;
using pii = pair<int, int>;
using vi = vector<int>;
using vvi = vector<vi>;

// #define rep(i,n) for(int i=0;i<(n);++i)
#define all(f,c,...) (([&](decltype((c)) cccc) { return (f)(begin(cccc), end(cccc), ## __VA_ARGS__); })(c))
#define _overload3(_1,_2,_3,name,...) name
#define _rep(i,n) for(int i=0;i<(n);++i)
#define repi(i,a,b) for(int i=(a);i<(b);++i)
#define rep(...) _overload3(__VA_ARGS__,repi,_rep,)(__VA_ARGS__)
#define _fromto2(i,n) for(int i=0;i<=(n);++i)
#define _fromto3(i,a,b) for(int i=(a);i<=(b);++i)
#define fromto(...) _overload3(__VA_ARGS__,_fromto3,_fromto2,)(__VA_ARGS__)

#define rrep(i,n) for(int i=(n);i>=0;--i)
const int MOD = 1e9+7;
const int INF = 1e9;
const int dx[4]={1,0,-1,0}, dy[4]={0,1,0,-1};
template<class T>bool chmax(T &a,const T &b){if(a<b){a=b;return 1;}return 0;}
template<class T>bool chmin(T &a,const T &b){if(b<a){a=b;return 1;}return 0;}

// debug
template<class T>ostream& operator<<(ostream& os,const vector<T>& vec){os<<"{";for(int i=0;i<vec.size();++i)os<<(i?", ":"")<<vec[i];os<<"}";return os;}
template<class T1,class T2>ostream& operator<<(ostream& os,const pair<T1,T2>& rhs){os<<"("<<rhs.first<<", "<<rhs.second<<")";return os;}

#ifdef LOCAL
void debug() {cerr << "\n";}
template<class First> void debug(const First& first) {cerr<<first<<"\n";}
template<class First, class... Rest> void debug(const First& first, const Rest&... rest) {cerr<<first<<",";debug(rest...);}
#else
#define debug(...) 42
#endif


int main() {
  ll a, b, c;
  cin >> a >>  b >>  c;

  if (a < 0) {
    a *= -1;
    b *= -1;
    c *= -1;
  }
  if (a == b && b == c && c == 0) {
    cout << -1 << endl;
    return 0;
  }

  if (a == 0) {
    if (b == 0 || c < 0) {
      cout << -1 << endl;
      return 0;
    }
    cout << 1 << endl;
    cout << (double)-c / b << endl;
    return 0;
  }

  ll D = b * b - 4 * a * c;
  if (D < 0) {
    cout << 0 << endl;
    return 0;
  }
  if (D == 0) {
    cout << 1 << endl;
    cout << fixed << setprecision(16) << (double)(-b) / (2 * a) << endl;
    return 0;
  }
  cout << 2 << endl;
  cout << fixed << setprecision(16) << (double)(-b - sqrt(D)) / (2 * a) << endl;
  cout << fixed << setprecision(16) << (double)(-b + sqrt(D)) / (2 * a) << endl;

  return 0;
}