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