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

print(ans)