import heapq
from collections import defaultdict

n, a = map(int, input().split())

ans = 0
hp = []
heapq.heappush(hp, [-n, 1])	# 降順にするため負値

while(len(hp) > 0):
	val, cnt = heapq.heappop(hp)
	val *= -1
	ans += cnt

	n_val = val // a
	if n_val > 0: heapq.heappush(hp, [-n_val, cnt*2])

print(ans)