#include <bits/stdc++.h>

using namespace std;

#define rep(i, n) for(int i = 0; i < (int)n; ++i)
#define FOR(i, a, b) for(int i = a; i < (int)b; ++i)
#define rrep(i, n) for(int i = ((int)n - 1); i >= 0; --i)

typedef long long ll;
typedef long double ld;

const int Inf = 1e9;
const double EPS = 1e-9;
const int MOD = 1e9 + 7;

int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(0);
    cout << fixed << setprecision(12);
    vector<ld> res;
    ll a, b, c, t;
    cin >> a >> b >> c;
    t = b * b - 4 * a * c;
    if (t < 0) {
        cout << 0 << endl;
        return 0;
    }
    if (a == 0) {
        if (b == 0 && c == 0) cout << -1 << endl;
        else if (b == 0 || c == 0) cout << 0 << endl;
        else cout << -1 << endl;
        return 0;
    }
    if (t == 0) res.push_back(-b / (ld)(2 * a));
    if (t > 0) {
        res.push_back(((-b) + sqrt((ld)t)) / (ld)(2 * a));
        res.push_back(((-b) - sqrt((ld)t)) / (ld)(2 * a));
    }
    sort(res.begin(), res.end());
    cout << res.size() << endl;
    rep (i, res.size()) cout << res[i] << endl;
    
    return 0;
}