#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
using namespace std;

//template
#define rep(i,a,b) for(int i=(a);i<(b);i++)
#define rrep(i,a,b) for(int i=(a);i>(b);i--)
#define ALL(v) (v).begin(),(v).end()
typedef long long int ll; const int inf = 0x3fffffff; const ll INF = 0x3fffffffffffffff;
template<class T> inline bool chmax(T& a,T b){ if(a<b){a=b;return 1;}return 0; }
template<class T> inline bool chmin(T& a,T b){ if(a>b){a=b;return 1;}return 0; }
//template end



int main(){
    ll a,b,c; scanf("%lld%lld%lld",&a,&b,&c);
    long double aa=a,bb=b,cc=c;
    if(a==0&&b==0)printf(c?"0\n":"-1\n");
    else if(a==0&&b!=0)printf("1\n%.15Lf\n",-cc/bb);
    else{
        long double d=bb*bb-4*aa*cc;
        if(d<-1e-23)printf("0\n");
        else if(d<=1e-23)printf("1\n%.15Lf\n",-bb/(2*aa));
        else{
            d=sqrt(d); double d1=(-bb+d)/(2*aa),d2=(-bb-d)/(2*aa);
            if(d1>d2)swap(d1,d2);
            printf("2\n%.15f\n%.15f\n",d1,d2);
        }
    }
    return 0;
}