#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
using namespace std;

__int64 a, b, c;

int main()
{
	int a, b, c;
	while (scanf("%d%d%d", &a, &b, &c) != EOF)
	{
		__int64 jd = (__int64)b*b - (__int64)4*a*c;
	//	printf("jd = %I64d\n", jd);
		if (a == 0)
		{
			if (b == 0 && c == 0)
				printf("-1\n");
			else if (b == 0 && c != 0)
                printf("0");
            else
				printf("1\n%.6lf\n", (double)-c/(double)b);
		}
		else if (jd < 0)
			printf("0\n");
		else if (jd == 0)
			printf("1\n%.6lf\n", (double)-b/(double)2*a);
		else
		{
		    double sq = sqrt(jd);
      //      printf("sq = %lf\n", sq);
			double f1 = (double)-b - sq;
			double f2 = (double)-b + sq;
			printf("2\n%.6lf\n%.6lf\n", f1/2*a, f2/2*a);
		}
	}
	return 0;
}
