#include <bits/stdc++.h>
#define rep(i,n) for(int i = 0; i < (n); i++)
using namespace std;
typedef long long ll;

int main(){
    cin.tie(0);
    ios::sync_with_stdio(0);
    
    using ld = long double;
    ld a,b,c; cin >> a >> b >> c;
    if(a == 0) {
        if(b == 0) {
            if(c == 0) {
                cout << -1 << endl;
            } else {
                cout << 0 << endl;
            }
        } else {
            cout << fixed << setprecision(20) << -c/b << endl;
        }
    } else {
        ld D = b * b - 4.0 * a * c;
        if(D < 0) {
            cout << 0 << endl;
        } else if(D == 0) {
            cout << 1 << endl;
            cout << fixed << setprecision(20) << -b/(2.0*a) << endl;
        } else {
            cout << 2 << endl;
            set<ld> st;
            st.insert((-b - sqrtl(D)) / (2.0 * a));
            st.insert((-b + sqrtl(D)) / (2.0 * a));
            for(ld x : st) cout << fixed << setprecision(20) << x << endl;
        }
    }
}