#include <iostream>
using namespace std;

int solve(int n,int f){
    int length=n,ans=n;
    if(f>n) return n;
    else while(length>=f){
           ans+=length/f;
           length=(length/f)+(length%f);
        }
    return ans;
}

int main()
{
    int n,f;
    cin>>n>>f;
    cout<<"ans ="<<solve(n,f);
    return 0;
}