#include <bits/stdc++.h>
using namespace std;
float a, b, c;
int main() {
  scanf("%f%f%f", &a, &b, &c);
  if (!a && !b && !c) {
    printf("-1");
    return 0;
  }
  if (!a) {
    if (!b || !c)
      printf("0");
    else {
      printf("-1\n");
      printf("%0.5f", -c / b);
      return 0;
    }
  }
  int delt = (b * b) - 4 * a * c;
  float x1 = (-b + sqrt(delt)) / (2 * a);
  float x2 = (-b - sqrt(delt)) / (2 * a);
  if (delt < 0) {
    printf("0");
    return 0;
  }
  if (x1 == x2) {
    printf("1\n");
    printf("%0.5f", x1);
    return 0;
  }
  if (x1 < x2) printf("2\n"), printf("%0.5f\n%0.5f", x1, x2);
  if (x1 > x2) printf("2\n"), printf("%0.5f\n%0.5f", x2, x1);
}
