#include <bits/stdc++.h>
using namespace std;
using LL = long long int;
#define incID(i, l, r) for(int i = (l)    ; i <  (r); ++i)
#define incII(i, l, r) for(int i = (l)    ; i <= (r); ++i)
#define decID(i, l, r) for(int i = (r) - 1; i >= (l); --i)
#define decII(i, l, r) for(int i = (r)    ; i >= (l); --i)
#define inc(i, n)  incID(i, 0, n)
#define inc1(i, n) incII(i, 1, n)
#define dec(i, n)  decID(i, 0, n)
#define dec1(i, n) decII(i, 1, n)
#define inID(v, l, r) ((l) <= (v) && (v) <  (r))
#define inII(v, l, r) ((l) <= (v) && (v) <= (r))
#define PB push_back
#define EB emplace_back
#define MP make_pair
#define FI first
#define SE second
#define  ALL(v)  v.begin(),  v.end()
#define RALL(v) v.rbegin(), v.rend()
auto setmin   = [](auto & a, auto b) { return (b <  a ? a = b, true : false); };
auto setmax   = [](auto & a, auto b) { return (b >  a ? a = b, true : false); };
auto setmineq = [](auto & a, auto b) { return (b <= a ? a = b, true : false); };
auto setmaxeq = [](auto & a, auto b) { return (b >= a ? a = b, true : false); };
auto fl = [](auto a, auto b) { assert(b != 0); return a / b - (a % b != 0 && ((a >= 0) != (b >= 0)) ? 1 : 0); };
auto ce = [](auto a, auto b) { assert(b != 0); return a / b + (a % b != 0 && ((a >= 0) == (b >= 0)) ? 1 : 0); };
auto mo = [](auto a, auto b) { assert(b != 0); a %= b; if(a < 0) { a += abs(b); } return a; };
LL gcd(LL a, LL b) { return (b == 0 ? a : gcd(b, a % b)); }
LL lcm(LL a, LL b) { return a / gcd(a, b) * b; }
#define bit(b, i) (((b) >> (i)) & 1)
#define SI(v) static_cast<int>(v.size())
#define RF(e, v) for(auto & e: v)
#define until(e) while(! (e))
#define if_not(e) if(! (e))
#define ef else if
#define UR assert(false)

// ---- ----

using LD = long double;

int main() {
	LL a, b, c, d;
	cin >> a >> b >> c;
	d = b * b - 4 * a * c;
	LD A = a, B = b, C = c, D = d;
	
	multiset<LD> ans;
	if(a != 0) {
		if(d <  0) { }
		if(d == 0) { ans.insert(-B / (2 * A)); }
		if(d >  0) {
			auto f  = [&](LD x) -> LD { return a * x * x + b * x + c; };
			auto fd = [&](LD x) -> LD { return 2 * a * x + b; };
			
			LD x0 = -(B + sqrt(D)) / (2 * A);
			LD x1 = -(2 * C) / (B + sqrt(D));
			inc(i, 3) {
				x0 -= f(x0) / fd(x0);
				x1 -= f(x1) / fd(x1);
			}
			ans.insert(x0);
			ans.insert(x1);
		}
	}
	ef(b != 0) {
		ans.insert(-C / B);
	}
	ef(c != 0) { } else { cout << -1 << endl; return 0; }
	
	cout << SI(ans) << endl;
	RF(e, ans) { printf("%.15Lf\n", e); }
	
	return 0;
}