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