#include <iostream>
#include <iomanip>
#include <cmath>
#include <algorithm>
#include <vector>

using lint = long long;
using ldouble = long double;

void solve() {
    lint a, b, c;
    std::cin >> a >> b >> c;
    if (b < 0) {
        a = -a, b = -b, c = -c;
    }

    ldouble af = a, bf = b, cf = c;

    std::vector<ldouble> ans;
    if (a == 0) {
        if (b == 0) {
            if (c == 0) {
                std::cout << -1 << "\n";
                return;
            }
        } else {
            ans.push_back(-cf / bf);
        }
    } else {
        lint d = b * b - a * c * 4;

        if (d == 0) {
            ans.push_back(-bf / (af * 2));

        } else if (d > 0) {
            auto df = bf * bf - af * cf * 4;
            ans.push_back(-cf * 2 / (bf + std::sqrt(df)));
            ans.push_back((-bf - std::sqrt(df)) / (af * 2));
        }
    }

    std::sort(ans.begin(), ans.end());
    std::cout << ans.size() << "\n";
    for (auto& x : ans) std::cout << x << "\n";
}

int main() {
    std::cin.tie(nullptr);
    std::ios::sync_with_stdio(false);
    std::cout << std::fixed << std::setprecision(20);

    solve();

    return 0;
}