a, b, h = map(int, input().split())
a, b = a*1000, b*1000
a, b = min(a, b), max(a, b)
c = 0
h1=h2=h
while a > h1:
    h1 *= 4
    h2 *= 2
    c += 1
while b > h2:
    h2 *= 4
    c += 1
print(c)