#include<bits/stdc++.h> using namespace std; double a,b,c,d; const double dx=0.001; double f(double x){ return a*x*x*x+b*x*x+c*x+d; } int main(){ cin>>a>>b>>c>>d; double l=-200,r=200; for(double x=l;x<=r;x+=dx){ if(f(x)*f(x+dx)<=0) printf("%.2f",x); } return 0; }