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)