x, y, h = map(int, input().split())

x *= 1000
y *= 1000
ans = 0

if x > y:
    x, y = y, x
    
while True:
    if h < x:
        h *= 4
        y *= 2
        ans += 1
    else:
        break
while True:
    if h < y:
        h *= 4
        x *= 2
        ans += 1
    else:
        break
print(ans)