#include <bits/stdc++.h>
using namespace std;
int main() {
  double a, b, c, det;
  cout.precision(15);
  cin >> a >> b >> c;
  det = b * b - 4 * a * c;
  if (a == 0 && b == 0 && c == 0)
    cout << -1;
  else if (a == 0 && b == 0 || det < 0)
    cout << 0;
  else if (a == 0)
    cout << 1 << endl << -c / b;
  else
    det == 0 ? cout << 1 << endl
                    << fixed << -1 * b / (2 * a)
             : cout << 2 << endl
                    << fixed << (-b - sqrt(det)) / (2 * a) << endl
                    << fixed << (-b + sqrt(det)) / (2 * a);
}
