foo.cpp:1:1: error: 'include' does not name a type
 include <iostream>
 ^
foo.cpp: In function 'double f(double)':
foo.cpp:11:8: error: 'axxx' was not declared in this scope
 return axxx+bxx+cx+d; }
        ^
foo.cpp:11:13: error: 'bxx' was not declared in this scope
 return axxx+bxx+cx+d; }
             ^
foo.cpp:11:17: error: 'cx' was not declared in this scope
 return axxx+bxx+cx+d; }
                 ^
foo.cpp: In function 'int main()':
foo.cpp:14:21: error: 'cin' was not declared in this scope
 double ans=-100.00; cin>>a>>b>>c>>d; for(;ans<=100.00;ans+=e) { if(f(ans)<eps && f(ans)>-eps) { printf("%.2lf ",ans); } }
                     ^
foo.cpp:14:116: error: 'printf' was not declared in this scope
 double ans=-100.00; cin>>a>>b>>c>>d; for(;ans<=100.00;ans+=e) { if(f(ans)<eps && f(ans)>-eps) { printf("%.2lf ",ans); } }
                                                                                                                    ^
foo.cpp: In function 'double f(double)':
foo.cpp:11:23: warning: control reaches end of non-void function [-Wreturn-type]
 return axxx+bxx+cx+d; }
                       ^