/*  This Code is Submitted by wywcgs for Problem 2017 on 2005-09-17 at 21:09:01 */ 
#include <stdio.h>

int main()
{
    long n, k, sum;
    
    while(scanf("%ld %ld", &n, &k) == 2) {
        sum = n;                
        while(n / k != 0) {
            sum += n / k;
            n = n / k + n % k;
        }
        printf("%ld\n", sum);                
    }
}