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

print(ans)