#include <bits/stdc++.h>

using i64 = long long;

void solve() {
    i64 x, y, a;
    std::cin >> x >> y >> a;
    
    i64 ans = 1E18;
    
    i64 dp[61][2];
    dp[0][0] = 0;
    dp[0][1] = 1;
    
    i64 v = y;
    for (int i = 1; i <= 60; i++) {
        i64 t = v % a;
        dp[i][0] = std::min(dp[i - 1][0] + t, dp[i - 1][1] + t + 1);
        dp[i][1] = std::min(dp[i - 1][0] + a - t, dp[i - 1][1] + a - t - 1);
        v /= a;
    }
    
    i64 cur = 0;
    while (true) {
        
        i64 v = y;
        for (int i = 0; i <= 60; i++) {
            ans = std::min(ans, cur + dp[i][0] + std::abs(x - v) + i);
            ans = std::min(ans, cur + dp[i][1] + std::abs(x - v - 1) + i);
            v /= a;
        }
        
        if (!x) {
            break;
        }
        cur++;
        x /= a;
    }
    
    std::cout << ans << "\n";
}

int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    
    int t;
    std::cin >> t;
    
    while (t--) {
        solve();
    }
    
    return 0;
}