Peter’s Smokes

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 43 10 3 100 5 Sample Output 5 14 124