#include <bits/stdc++.h>

using namespace std;

signed main() {
    int T; scanf("%d", &T);
    while (T--) {
        double n, k; cin >> n >> k;
        printf("%.10lf\n", ln(3) * n - 9.99);
    }
    return 0;
}

answer.code: In function ‘int main()’:
answer.code:9:28: error: ‘ln’ was not declared in this scope; did you mean ‘n’?
    9 |         printf("%.10lf\n", ln(3) * n - 9.99);
      |                            ^~
      |                            n
answer.code:6:17: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
    6 |     int T; scanf("%d", &T);
      |            ~~~~~^~~~~~~~~~