#include <stdio.h>

#include <stdlib.h>

int main()

{

    int now,k;

    while(scanf("%d %d",&now,&k) != EOF)

    {

        int hav=;

        while(now >= k)

        {

            hav +=   now/k*k;

            now = now/k + now%k;

        }

        hav += now;

        printf("%d\n",hav);

    }

    return ;

}