#include<stdio.h>
#include<assert.h>
#include<math.h>
int main(){
  long long a, b, c, p;
  scanf("%lld%lld%lld", &a, &b, &c);
  if (a){
    if (a < 0){
      a = -a;
      b = -b;
      c = -c;
    }
    p = b*b-a*c*4;
    if (!p) printf("1\n%.14Lf\n", -b*0.5l / a);
    else if (p>0) {
      long double s = -0.5*(sqrtl(p) + b) / a;
      long double t = (sqrtl(p) - b)*0.5 / a;
      if (s < 0) s -= 5e-12;
      else s += 5e-12;
      if (t < 0) t -= 5e-12;
      else t += 5e-12;
      printf("2\n%.14Lf\n%.14Lf\n", s, t);
    }
    else puts("0");
  }
  else{
    if (b) printf("1\n%.14Lf\n", -c / (long double)b);
    else puts(c ? "0" : "-1");
  }
  return 0;
}