#include using namespace std; using ll = long long; using VI = vector; using VL = vector; using VS = vector; using VB = vector; using VVI = vector; using VVL = vector; using PII = std::pair; using PLL = std::pair; using TI3 = std::tuple; using TI4 = std::tuple; using TL3 = std::tuple; using TL4 = std::tuple; #define rep(i, n) for (int i = 0; i < (int)(n); i++) #define repr(i, n) for (int i = (int)(n)-1; i >= 0; i--) #define rep2(i, s, n) for (int i = (s); i < (int)(n); i++) #define rep3(i, s, n, d) for (int i = (s); i < (int)(n); i += (d)) #define allpt(v) (v).begin(), (v).end() #define allpt_c(v) (v).cbegin(), (v).cend() #define allpt_r(v) (v).rbegin(), (v).rend() const int mod1 = 1e9 + 7, mod2 = 998244353, mod3 = 1e9 + 9; const int mod = mod1; const ll inf = 1e18; const string wsp = " "; const string tb = "\t"; const string rt = "\n"; template void show1dvec(const vector &v) { if (v.size() == 0) return; int n = v.size() - 1; rep(i, n) cout << v[i] << wsp; cout << v[n] << rt; return; } template void show2dvec(const vector> &v) { int n = v.size(); rep(i, n) show1dvec(v[i]); } template void show1dpair(const vector> &v) { int n = v.size(); rep(i, n) cout << v[i].first << wsp << v[i].second << rt; return; } template void pairzip(const vector> &v, vector &t, vector &s) { int n = v.size(); rep(i, n) { t.push_back(v[i].first); s.push_back(v[i].second); } return; } template void maxvec(vector &v) { T s = v[0]; int n = v.size(); rep(i, n - 1) { if (s > v[i + 1]) { v[i + 1] = s; } s = v[i + 1]; } } template bool myfind(T t, S s) { return find(t.cbegin(), t.cend(), s) != t.cend(); } bool check(int y, int x, int h, int w) { return 0 <= y && y < h && 0 <= x && x < w; } template vector cumsum(const vector &v) { T s = 0; vector ret; rep(i, v.size()) { s += v[i]; s %= mod; ret.emplace_back(s); } return ret; } bool iskadomatsu(int a, int b, int c) { return (a != b && b != c && c != a) && ((a > b && b < c) || (a < b && b > c)); } VS split(string s, char c) { VS ret; string part; s += c; rep(i, s.length()) { if (s[i] == c) { ret.emplace_back(part); part = ""; } else if (s[i] != c) { part += s[i]; } } return ret; } string removezero(string &s) { string ret; for (auto z : s) if (z != '0') ret += z; return ret; } ll sumdigit(ll x) { ll ans{0}; while (x > 0) { ans += x % 10; x /= 10; } return ans; } template ll pow_mod(T p, S q, R mod = 1ll) { ll ret = 1, r = p; while (q) { if (q % 2) ret *= r, ret %= mod; r = (r * r) % mod, q /= 2; } return ret % mod; } template ll pow_no_mod(T p, S q) { ll ret = 1, r = p; while (q) { if (q % 2) ret *= r; r = (r * r), q /= 2; } return ret; } void make_frac_tables(VL &frac_list, VL &frac_inv_list) { rep(i, frac_list.size() - 1) { frac_list[i + 1] *= frac_list[i] * (i + 1); frac_list[i + 1] %= mod; frac_inv_list[i + 1] *= frac_inv_list[i] * pow_mod(i + 1, mod - 2, mod); frac_inv_list[i + 1] %= mod; } } ll comb(int a, int b, const VL &frac_list, const VL &frac_inv_list) { if (a < b) return 0; if (b < 0) return 0; ll ret = frac_list[a]; ret *= frac_inv_list[b]; ret %= mod; ret *= frac_inv_list[a - b]; ret %= mod; return ret; } ll getmedian_double(VL v) { ll ret; sort(allpt(v)); int n = v.size(); if (n % 2 == 0) { ret = v[n / 2] + v[n / 2 - 1]; } else { ret = 2 * v[n / 2]; } return ret; } class RangeMinorMaxorSumQuery // 0-index { int const intmax = 2147483647; int const intmin = 0; vector sgt; int n; int k; public: RangeMinorMaxorSumQuery(int n1, int f = -1) { if (f == -1) f = intmax; else if (f == 0) f = intmin; int na = 1; int ka = 0; while (na < n1) { na *= 2; ka++; } for (int i = 0; i < 2 * na; i++) sgt.push_back(f); n = na; k = ka; } void update_min(int i, int x) { i += n; sgt[i] = x; while (i > 1) { i /= 2; sgt[i] = min(sgt[2 * i], sgt[2 * i + 1]); } } void update_max(int i, int x) { i += n; sgt[i] = x; while (i > 1) { i /= 2; sgt[i] = max(sgt[2 * i], sgt[2 * i + 1]); } } void update_sum(int i, int x) { i += n; sgt[i] = x; while (i > 1) { i /= 2; sgt[i] = sgt[2 * i] + sgt[2 * i + 1]; } } void add_sum(int i, int x) { i += n; sgt[i] += x; while (i > 1) { i /= 2; sgt[i] = sgt[2 * i] + sgt[2 * i + 1]; } } int getmin(int a, int b, int k = 1, int l = 0, int r = -1) //閉区間 l <= x < r とする { if (r == -1) r = n; if (r <= a || b <= l) return intmax; if (a == l && b == r) return sgt[k]; else return min(getmin(a, min(b, (l + r) / 2), 2 * k, l, (l + r) / 2), getmin(max(a, (l + r) / 2), b, 2 * k + 1, (l + r) / 2, r)); } int getmax(int a, int b, int k = 1, int l = 0, int r = -1) //閉区間 l <= x < r とする { if (r == -1) r = n; if (r <= a || b <= l) return intmin; if (a == l && b == r) return sgt[k]; else return max(getmax(a, min(b, (l + r) / 2), 2 * k, l, (l + r) / 2), getmax(max(a, (l + r) / 2), b, 2 * k + 1, (l + r) / 2, r)); } int getsum(int a, int b, int k = 1, int l = 0, int r = -1) //閉区間 l <= x < r とする { if (r == -1) r = n; if (r <= a || b <= l) return intmin; if (a == l && b == r) return sgt[k]; else return getsum(a, min(b, (l + r) / 2), 2 * k, l, (l + r) / 2) + getsum(max(a, (l + r) / 2), b, 2 * k + 1, (l + r) / 2, r); } void printsegtree() { for (int i = 0; i < 2 * n; i++) { cout << sgt[i] << " "; } cout << endl; } }; int main() { cin.tie(0); ios::sync_with_stdio(false); #ifdef DEBUG cout << "DEBUG MODE" << endl; ifstream in("input.txt"); //for debug cin.rdbuf(in.rdbuf()); //for debug #endif ll ai, bi, ci; double a, b, c, d; cin >> ai >> bi >> ci; a = 1.0 * ai; b = 1.0 * bi; c = 1.0 * ci; if (a == 0) { if (b == 0) { if (c == 0) { cout << -1 << rt; } else { cout << 0 << rt; } } else { cout << 1 << endl; printf("%.12f\n", -c / b); } } else { if (bi * bi - 4 * ai * ci > 0) { d = b * b - 4 * a * c; if (b < 0) b *= -1.0; cout << 2 << endl; printf("%.12f\n", (-b - sqrt(d)) / (2.0 * a)); printf("%.12f\n", (-b + sqrt(d)) / (2.0 * a)); } else if (bi * bi - 4 * ai * ci == 0) { cout << 1 << endl; printf("%.12f\n", -b / (2.0 * a)); } else { cout << 0 << rt; } } return 0; }