#include <bits/stdc++.h>
using namespace std;
const int mod = (int)1e9 + 7;
int a, b, c;
int main() {
  ios_base::sync_with_stdio(0), cin.tie(0);
  cin >> a >> b >> c;
  if (a == 0 && b == 0) {
    if (c != 0) return cout << "0\n", 0;
    return cout << "-1\n", 0;
  }
  cout.precision(6);
  if (a == 0) {
    cout << 1 << endl;
    cout << fixed << -c * 1.0 / b << endl;
    return 0;
  }
  double d = b * 1ll * b - 4 * 1ll * a * c;
  if (d < 0) return cout << "0\n", 0;
  if (d == 0) {
    cout << "1\n";
    cout << fixed << -b * 1.0 / 2 / a << endl;
    return 0;
  }
  cout << 2 << endl;
  cout << fixed << (-b - sqrt(d)) / 2.0 / a << endl;
  cout << fixed << (-b + sqrt(d)) / 2.0 / a << endl;
}
