// Problem: P1024 [NOIP2001 提高组] 一元三次方程求解 // URL: https://www.luogu.com.cn/problem/P1024 // Author: Pengfei Xu #include<iostream> //#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; }