搜不到答案

#include<bits/stdc++.h>
using namespace std;
int main() {
	double a,b,c,d;
	cin >> a >> b >> c >> d;
	for(double i=-100.0;i<=100.0;i+=0.001){
		if(fabs((a*i*i*i+b*i*i*i+c*i+d)) <= 0.00001){
			printf("%.2lf ",i); 
		}
	} 
	return 0;
}