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