5 3
 1000 3
 777 17
 4 3
 2 2
 100 4
 10 4
 999 2
 6 4
 1 2
 17 3
 1 4
 26 8
 91 5
 1 3
 1000 2
 20 3
 9 4
 123 5
 1000 1000
 3 2
 3 3
 80 970
 1000 4
 1 1000

7
 1499
 825
 5
 3
 133
 13
 1997
 7
 1
 25
 1
 29
 113
 1
 1999
 29
 11
 153
 1001
 5
 4
 80
 1333
 1

import sys
import math

def main():
	inputString = raw_input()
	inputList = inputString.split()
	candlesAvailable = int(inputList[0])
	usedCandleCost = int(inputList[1])
	totalHours = 0
	extraCandles = 0
	while (candlesAvailable >= 1):
		totalHours += candlesAvailable
		candlesAvailable = math.floor(candlesAvailable / usedCandleCost) 
		extraCandles += candlesAvailable % usedCandleCost
		if (extraCandles >= usedCandleCost):
			candlesToAdd = math.floor(extraCandles / usedCandleCost);
			candlesAvailable += candlesToAdd;
			extraCandles -= candlesToAdd * usedCandleCost
	print int(totalHours)

if __name__ == "__main__":
	main()