#include <bits/stdc++.h>
using namespace std;
int main(){
	double a,b,c,d;
	cin>>a>>b>>c>>d;
	for(double i=-100;i<=100;i+=0.001){
		double k=i+0.001;
	    if((a*i*i*i+b*i*i+c*i+d)*(a*k*k*k+b*k*k+c*k+d)<0);
		printf("%0.2lf",i);
	}
	return 0;
}