import java.util.*;

public class c20B{
	
	public static void main(String[] args){
		Scanner in = new Scanner(System.in);
		int a = in.nextInt();
		int b = in.nextInt();
		int c = in.nextInt();
		if(a == 0){//linear
			if(b == 0){//constant
				if(c==0)
					System.out.println(0);
				else
					System.out.println(-1);
			}
			else{//actually linear
				//y = bx +c (b nonzero)
				//0 = bx +c  to find root
				//-bx = c
				// x = (-c/b)
				System.out.println(1);
				System.out.println((-1.0*c)/b);
			}
		}
		else{//use quadratic formula
			//b^2 - 4ac
			int discriminant = (b*b) - (4*a*c);
			if(discriminant < 0){//no roots
				System.out.println(-1);
			}
			else if(discriminant == 0){//1 root
				System.out.println(1);
				System.out.println((-1.0*b)/(2*a));
			}
			else{//2 roots
				double root1 = ((-1.0*b) + Math.sqrt(discriminant))/(2*a);
				double root2 = ((-1.0*b) - Math.sqrt(discriminant))/(2*a);
				System.out.println(2);
				if(root1 < root2){
					System.out.println(root1);
					System.out.println(root2);
				}
				else{
					System.out.println(root2);
					System.out.println(root1);
				}
			}
		}
	}
}

