a,b,c=map(int,input().split())
count=0
while a*1000>c:
    a/=2
    a=float.fromhex(a.hex())
    c*=2
    count+=1
while b*1000>c:
    b/=2
    b=float.fromhex(b.hex())
    c*=2
    count+=1
print(count)