#include <bits/stdc++.h>
using namespace std;
int main() {
  double a, b, c;
  cin >> a >> b >> c;
  if (a == 0) {
    if (b == 0 && c != 0) {
      cout << "0" << endl;
    }
    if (c == 0 && b != 0) {
      cout << "1" << endl << "0";
    }
    if (b != 0 && c != 0) {
      cout << "1" << endl;
      double x = -1.0 * c / b;
      printf("%.10f", x);
    }
  }
  if (b == 0) {
    if (a != 0 && c == 0) {
      cout << "1" << endl << "0";
    }
    if (c != 0 && a != 0 && (c / a) <= 0) {
      double x = sqrt(-c / a);
      printf("1\n%.10f", x);
    }
    if (a == c && c != 0) cout << "0";
  }
  if (c == 0) {
    if (a != 0 && b != 0) {
      double x = -b / a;
      if (x < 0) {
        cout << x << endl << "0";
      } else if (x > 0) {
        cout << "0 " << endl << x;
      }
    }
  }
  if (a != 0 && b != 0 && c != 0) {
    if ((b * b - 4 * a * c) >= 0) {
      double x = (-b + sqrt(b * b - 4.0 * a * c)) / (2.0 * a);
      double x2 = (-b - sqrt(b * b - 4 * a * c)) / (2.0 * a);
      if (sqrt(b * b - 4 * a * c) == 0) {
        x = -b / (2 * a);
        printf("1\n%.10f", x);
      } else {
        if (x < x2) {
          swap(x, x2);
        }
        printf("2\n%.10f %.10f", x2, x);
      }
    } else {
      cout << "0";
    }
  }
  if (a == 0 && b == 0 && c == 0) cout << "-1";
  return 0;
}
