x, y, h = map(int, input().split())
x *= 1000
y *= 1000
if x > y:
    x, y = y, x
cnt = 0

while x > h:
    x /= 2
    h *= 2
    cnt += 1

while y > h:
    y /= 2
    h *= 2
    cnt += 1

print(cnt)