#include<iostream>
using namespace std;
int main(){
    int n, k;
    cin >> n >> k;
    int sum = n, sump = 0, m;
    while (n >= k){
        n = n % k;
        sump = sum - (n * k);
        m = n + sump;
        sum = sum + n;
        n = m;
    }
    cout << sum;
    return 0;
}

1 AC

23 TLE

4~10 WA

求解