from decimal import *
getcontext().prec = 50

a,b,c=map(int,input().split())
a,b,c=Decimal(a),Decimal(b),Decimal(c)

if a==b==0:
    if c==0:
        print(-1)
    else:
        print(0)
        
elif a==0:
    x=-c/b
    print(1)
    print(x)
else:
    D=b**2-4*a*c
    if D<0:
        print(0)
    elif D==0:
        x=-b/(2*a)
        print(1)
        print(x)
    else:
        k=D**(Decimal(0.5))
        if a>0:
            print(2)
            print((-b-k)/(2*a))
            print((-b+k)/(2*a))
        else:
            print(2)
            print((-b+k)/(2*a))
            print((-b-k)/(2*a))