poj 2509 Peter's smokes

Peter's smokes

Time Limit: 1000MS		Memory Limit: 65536K
Total Submissions: 15268		Accepted: 6171

Description

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.

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

#include<iostream>
using namespace std;
int main()
{
    int n,k;
    int sum;
    while(scanf("%d%d",&n,&k)!=EOF)
    {
        sum=n;
        while(n/k!=0)
        {
            sum+=n/k;
            n=n%k+n/k;    
        }
        cout<<sum<<endl;
    }
    return 0;
}