#include<bits/stdc++.h>
namespace {
#pragma GCC diagnostic ignored "-Wunused-function"
#include<atcoder/all>
#pragma GCC diagnostic warning "-Wunused-function"
using namespace std;
using namespace atcoder;
#define rep(i,n) for(int i = 0; i < (int)(n); i++)
#define rrep(i,n) for(int i = (int)(n) - 1; i >= 0; i--)
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)
template<class T> bool chmax(T& a, const T& b) { if (a < b) { a = b; return true; } else return false; }
template<class T> bool chmin(T& a, const T& b) { if (b < a) { a = b; return true; } else return false; }
using ll = long long;
using P = pair<int,int>;
using VI = vector<int>;
using VVI = vector<VI>;
using VL = vector<ll>;
using VVL = vector<VL>;

} int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int tt;
  cin >> tt;
  while (tt--) {
    int n;
    cin >> n;
    int a2 = 0, a5 = 0;
    rep(i, n) {
      string s;
      cin >> s;
      if (i == 0) continue;
      int a = stoi(s);
      if (a == 0) continue;
      // a/10^c
      int v2 = ssize(s), v5 = ssize(s);
      while (a % 2 == 0) a /= 2, v2--;
      while (a % 5 == 0) a /= 5, v5--;
      chmax(a2, v2);
      chmax(a5, v5);
    }
    ll ans = 1;
    rep(_, a2) ans *= 2;
    rep(_, a5) ans *= 5;
    cout << ans << '\n';
  }
}