import queue

h,a = map(int,input().split())
sr = queue.LifoQueue()
sr.put(h)
ans = 0

while True:
  if sr.empty():
    print(ans-1)
    exit()
  else:
    h_now = sr.get()
    if h_now//a!=0:
      sr.put(h_now//a)
    ans += 2