#include <bits/stdc++.h>

using namespace std;

using ll =  long long;
using Pll = pair<ll, ll>;
using Pii = pair<int, int>;

constexpr ll MOD = 1000000007;
constexpr ll INF = 1LL << 60;
constexpr long double EPS = 1e-10;
constexpr int dyx[4][2] = {
    { 0, 1}, {-1, 0}, {0,-1}, {1, 0}
};

void solve() {
    ll a, b, c, ans = 0;
    cin >> a >> b >> c;

    if(c == 1) {
        cout << c * b << endl;
        return;
    }

    ll c_pow = 1LL, ci = 0LL;
    for(ci=0;c_pow*c<=a;++ci) {
        c_pow = c_pow * c;
    }

    deque<ll> digits;
    ll a_copy = a, c_pow_copy = c_pow;
    for(ll i=0;i<=ci;++i) {
        digits.push_back(a_copy/c_pow_copy);
        a_copy -= a_copy / c_pow_copy * c_pow_copy;
        c_pow_copy /= c;
    }

    for(int i=0;i<ci;++i) {
        if(digits[i] == 1) {
            digits[i+1] += c;
            digits[i] = 0;
        }
    }
    while(digits.front() == 0) digits.pop_front();

    for(int i=0;i<digits.size();++i) {
        if(digits[i]) {
            ans += (digits[i]+c-2)/(c-1);
        }
        ++ans;
    }
    --ans;

    ans *= b;
    cout << ans << endl;
}

int main() {
    ios::sync_with_stdio(false); cin.tie(nullptr);
    int q;
    cin >> q;
    while(q--) {
        solve();
    }
}