import math as m
a,b,c = map(int, input().split())
if a == 0:
    if b == 0:
        if c == 0:
            print(-1)
        else:
            print(0)
    else:
        print(1,c/b,sep='\n')
else:
    if b*b-4*a*c>=0:
        p,q=(-b-m.sqrt(b*b-4*a*c))/2/a,(-b+m.sqrt(b*b-4*a*c))/2/a
        if p!=q:
            print(2,p,q,sep='\n')
        else:
            print(1,p,sep='\n')
    else:
        print(0)