x, y, h = map(int, input().split())
cnt = 0
while True:
    if x * 1000 > h and y * 1000 > h:
        if x < y:
            x /= 2
            h *= 2
        else:
            y /= 2
            h *= 2
    elif x * 1000 > h:
        x /= 2
        h *= 2
    elif y * 1000 > h:
        y /= 2
        h *= 2
    else:
        break
    cnt += 1
print(cnt)