代码如下

#include <iostream>
using namespace std;
int main(){
	int n , k;
	cin >> n >> k;
	int flag = n ;
	for (int i = 0; ; ++i)
	{
		flag = flag + n / k;
		if (n / k < k)
		{
			break;
		}
		n = n / k;
	}
	cout << flag << endl;
	return 0;
}