#include <bits/stdc++.h>
using namespace std;
inline void solve();
int main() {
  solve();
  return 0;
}
inline void solve() {
  double a, b, c;
  cin >> a >> b >> c;
  if (a == 0 && b == 0 && c == 0) {
    cout << -1;
    return;
  }
  if (a == 0 && b != 0 && c != 0) {
    cout << 1 << endl;
    cout << -c / b;
    return;
  }
  if (a == 0 && b == 0) {
    cout << -1 << endl;
  }
  double d = b * b - 4 * a * c;
  if (d < 0) {
    cout << 0;
    return;
  }
  if (d == 0) {
    cout << 1 << endl;
    cout << (-b + sqrt(d)) / 2 / a;
    return;
  }
  cout << 2 << endl;
  cout << fixed << setprecision(6) << (-b - sqrt(d)) / 2 / a << endl;
  cout << fixed << setprecision(6) << (-b + sqrt(d)) / 2 / a << endl;
}
