#include<bits/stdc++.h>
using lint=long long;
using real=long double;
int main(){
    std::cin.tie(nullptr);std::ios_base::sync_with_stdio(false);
    std::cout.setf(std::ios_base::fixed);std::cout.precision(30);
    lint a,b,c;std::cin>>a>>b>>c;
    auto ans=[a,b,c]()->std::vector<real>{
        if(a==0){
            if(b==0){
                if(c==0){
                    std::cout<<-1<<'\n';
                    exit(0);
                }
                return {};
            }
            return {-real{c}/b};
        }
        lint D=b*b-4*a*c;
        real x=-real{b}/(2*a);
        if(D<0)return {};
        if(D==0)return {x};
        real y=real(4)*a*c/(b*b);
        return {x*(1+std::sqrt(1-y)),std:abs(y)<1e-6
            ?x*(-y/2-y*y/8-y*y*y/16)
            :x*(1-std::sqrt(1-y))};
    }();
    std::sort(ans.begin(),ans.end());
    std::cout<<ans.size()<<'\n';
    for(real x:ans){
        std::cout<<x<<'\n';
    }
}