#include <bits/stdc++.h>
int main() {
  double a, b, c;
  scanf("%lf %lf %lf", &a, &b, &c);
  if (a == 0) {
    if (b == 0) {
      puts(c ? "0" : "-1");
    } else {
      printf("1\n%.6lf\n", -c / b);
    }
  } else {
    if (a < 0) {
      a = -a;
      b = -b;
      c = -c;
    }
    double d = b * b - 4 * a * c;
    if (d < 0) {
      puts("0");
    } else if (d == 0) {
      printf("1\n%.6lf\n", -b / (2 * a));
    } else if (d > 0) {
      printf("2\n%.6lf\n%.6lf\n", (-b - sqrt(d)) / (2 * a),
             (-b + sqrt(d)) / (2 * a));
    }
  }
  return 0;
}
