C++ :

#include<iostream>

#include<cmath>

using namespace std;

double x[3];

double a,b,c,d,u,v;

int i,t;

double f(double x)

 {

     double temp;

     temp=((a*x+b)*x+c)*x+d;

     return temp;

 }    

int main()

 {  

         while(cin>>a>>b>>c>>d)

      {

          t=-1;

          for(i=-100;i<=100;i++)

           {

               u=double(i);

               v=u+0.99999;

               if(fabs(f(u))<0.00001||f(u)*f(v)<=0)

                {

                    t++;

                    if(fabs(f(u))<0.00001)

                       x[t]=u;

                    else

                       {

                        while((u+0.001<v)&&fabs(f((u+v)/2))>=0.00001)   

                           

                           {

                               if(f(u)*f((u+v)/2)<0)

                                 v=(u+v)/2;

                               else

                                 u=(u+v)/2;  

                           } 

                        x[t]=(u+v)/2;      

                       }       

                }    

           }    

      cout.setf(ios::fixed);

      cout.precision(2);

      cout<<x[0]<<" "<<x[1]<<" "<<x[2]<<endl;

      } 

     

     return 0;

 }    

Pascal :

Program a2;
Var
    t,k:integer;
    a,b,c,d,x:extended;
    ans:array[1..3] of extended;
Function f(x:extended):extended;
   Begin
        f:=a*x*x*x+b*x*x+c*x+d;
   End;

Begin
    t:=0;
    Read(a,b,c,d);
    For k:=-10000 to 10000 do
        Begin 
            x:=k/100;
            If  (f(x-0.005)*f(x+0.005)<0 ) or  (f(x-0.005)=0) then 
             begin
                inc(t);
                ans[t]:=x;
             end;
        End;
    writeln(ans[1]:0:2,' ',ans[2]:0:2,' ',ans[3]:0:2);
End.