/* Arithmetic: Cubic equation solver
   =================================================================
   Description: Finds solutions to the cubic equation:
                           ax^3+bx^2+cx+d = 0
  
   Complexity:  O(1)
   -----------------------------------------------------------------
   Author:      Gilbert Lee
   Date:        Sept 8, 2002
   References:  www.snippets.org/snippets/portable/CUBIC+C.php3
   -----------------------------------------------------------------
   Reliability: 0
   Notes:      
*/

#include <stdio.h>
#include <math.h>

typedef struct{
  int n;        /* Number of solutions */
  double x[3];  /* Solutions */
} Result;

double PI;

Result solve_cubic(double a, double b, double c, double d){
  Result s;
  long double a1 = b/a, a2 = c/a, a3 = d/a;
  long double q = (a1*a1 - 3*a2)/9.0, sq = -2*sqrt(q);
  long double r = (2*a1*a1*a1 - 9*a1*a2 + 27*a3)/54.0;
  double z = r*r-q*q*q;
  double theta;

  if(z <= 0){
    s.n = 3;
    theta = acos(r/sqrt(q*q*q));
    s.x[0] = sq*cos(theta/3.0) - a1/3.0;
    s.x[1] = sq*cos((theta+2.0*PI)/3.0) - a1/3.0;
    s.x[2] = sq*cos((theta+4.0*PI)/3.0) - a1/3.0;
  } else {
    s.n = 1;
    s.x[0] = pow(sqrt(z)+fabs(r),1/3.0);
    s.x[0] += q/s.x[0];
    s.x[0] *= (r < 0) ? 1 : -1;
    s.x[0] -= a1/3.0;
  }
  return s;
}

int main(){
  double a,b,c,d;
  Result r;
  int i;

  PI = acos(-1);
  while(scanf("%lf %lf %lf %lf", &a, &b, &c, &d) == 4){
    r = solve_cubic(a,b,c,d);
    printf("%d solution(s)\n", r.n);
    for(i = 0; i < r.n; i++){
      printf("x = %f\n", r.x[i]);
    }
  }
  return 0;
}