#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
#define ll long long
#define rep(i,a,b) for(int i=(a);i<(b);i++)
#define repl(i,a,b) for(ll i=(a);i<(b);i++)
#define all(a) (a).begin(),(a).end()
#define rall(a) (a).rbegin(),(a).rend()

template <typename T> bool chmin(T &a,T b){if(a>b){a=b;return true;} return false;}
template <typename T> bool chmax(T &a,T b){if(a<b){a=b;return true;} return false;}


void solve(){
  int n; cin >> n;
  int d2=0,d5=0;
  auto f=[](int x) -> int{
    int res=0;
    while(x){
      res++;
      x/=10;
    }
    return res;
  };
  rep(i,0,n){
    int a; cin >> a;
    if(i == 0 || a == 0) continue;
    int dig=f(a);
    int x=0,y=0;
    while(a%2 == 0){
      x++;
      a/=2;
    }
    while(a%5 == 0){
      y++;
      a/=5;
    }
    chmax(d2,dig-x),chmax(d5,dig-y);
  }
  ll ans=1;
  rep(i,0,d2) ans*=2;
  rep(i,0,d5) ans*=5;
  cout << ans << "\n";
}

int main(){
  ios::sync_with_stdio(false);
  cin.tie(nullptr);

  int T; cin >> T;
  while(T--) solve();
}