import sys
input=lambda: sys.stdin.readline().rstrip()
x,y,h=map(int,input().split())
x,y=x*1000,y*1000
if x<=y:
  x,y=y,x
ans=0
while y>h:
  ans+=1
  y/=2
  h*=2
while x>h:
  ans+=1
  x/=2
  h*=2
print(ans)