1.

/**
 * FWP, Ausgewählte Probleme aus dem ACM Programming Contest, SS10 
 * Problem: 10346 Peter's Smokes
 * Link: http://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=15&page=show_problem&problem=1287
 * 
 * @author Anton Pavlushko, IBB7B,  
 * @version 1.0, 28/11/2010
 * 
 * Status : Accepted
 * Runtime: 0.120
 */

import java.io.*;
import java.text.*;
import java.util.*;
public class Main {
	
	public static void main(String[] args) throws IOException {
	    BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
	    String current_line, empty = "";
        int number, border, i, j, length, number_local;
        int primes [];
        Iterator iter;
        NumberFormat f;
        Formatter f1, f2, f3;
        StringTokenizer input_string;
        int count,n,k;
        String line_1, line_2;
        
	     try {
	    	 while((current_line=in.readLine())!= null) {
	    		 input_string = new StringTokenizer(current_line);
		    	 n=Integer.parseInt(input_string.nextToken());
		    	 k=Integer.parseInt(input_string.nextToken());
		    	 
		    	 count=n;
	    	 	 while (n/k>0) {
		    		 count+=n/k;
		    		 n=n/k+n%k;
		    	 };
		    	 
	        	 System.out.println(count);
	    	 }
	    	 
	       } // end try
	       catch (IOException ee) {
	         System.err.println("Error: " + ee);
	       }
	}
}


2. 

/**
 * FWP, Ausgewählte Probleme aus dem ACM Programming Contest, SS10
 * Problem: 10346 Peter's Smokes
 *
 * @author Robert Reichart
 *
 * Status : Accepted
 * Runtime: 0.144
 */

import java.util.*;
class Main{
    public static void main(String... args){
        Scanner in = new Scanner(System.in);
        while (in.hasNextInt())
        {
            int n = in.nextInt();
            int k = in.nextInt();
            int total_cigar=0;
            int butt=0;
            while (n > 0) {
                total_cigar += n; /* accumulate all new cigars so far */
                butt += n; /* after Peter smokes these n cigar, we have n butts */
                n = butt / k; /* so these n butts become new cigars */
                butt %= k; /* butts left are reserved for future cigars */
            }
            System.out.println(total_cigar);
        }
    }
}