T320362 Peter 的饮料

#include<iostream>
using namespace std;
int main(){
	int n,k;
	cin>>n>>k;
	int ans=n,s=n;
	while(s>=k){
	    ans+=s/k;
	    s=s/k+s%k;
	}
	cout<<ans<<endl;
	return 0;
}