x, y, h = map(int, input().split())
x, y = min(x, y), max(x, y)
x *= 1000
y *= 1000
ans = 0
while x > h:
    ans += 1
    x /= 2
    h *= 2
while y > h:
    ans += 1
    y /= 2
    h *= 2
print(ans)