## Setting

Peter has n cigarettes. He smokes them one by one keeping all the butts. Out of k > 1 butts he can roll a new cigarette. How many cigarettes can Peter have?

## Input

Input is a sequence of lines. Each line contains two integer numbers giving the values of n and k. The input is terminated by end of file.

## Output

For each line of input, output one integer number on a separate line giving the maximum number of cigarettes that Peter can have.

## Sample Input

4 3
10 3
100 5


## Sample Output

5
14
124


This challenge is provided by the ACM International Collegiate Programming Contest.

## Statistics

 Difficulty (6 votes) Average test runtime 0.22 Points (changes over time) 10 Tried by 21 users Solved by 18 users

## Global ranking

# Name Runtime Points worth
1 Justin 0.13 15
2 Brian 0.13 15
3 ,s/java/NaN/gi 0.13 15
4 Daniel 0.14 14
5 mascent 0.15 13
6 Dark 0.16 12
7 Pascal 0.16 12
8 Irfan 0.16 12
9 JB 0.19 10
10 Melf 0.21 9
11 Chris Danger 0.21 9
12 Phatti McButterpants 0.23 8
13 Finn-Lasse 0.27 7
14 Mac 0.27 7
15 Birger 0.30 6
16 Soeren 0.33 6
17 Nis 0.37 5
18 IeM 0.39 5