hdoj  acm   1555

#include<stdio.h>

intmain()

{

   int n,m;

   int sum;

   while(scanf("%d%d",&n,&m))

   {

       sum=0;

       if(n==0&&m==0)

           break;

       if(n==0)

           printf("%d\n",sum);

       else

       {

           while(1)

           {

               if(n>=m)

               {

                   n=n-m;

                   sum+=m;

                   n=n+1;

               }

               else

               {

                   sum+=n;

                   break;

               }

           }

           printf("%d\n",sum);

       }

   }

   return 0;

}