#include <bits/stdc++.h>
using namespace std;
using ll = long long;

ll pow_10[11] = {(ll)1e0, (ll)1e1, (ll)1e2, (ll)1e3, (ll)1e4, (ll)1e5, (ll)1e6, (ll)1e7, (ll)1e8, (ll)1e9, (ll)1e10};

// n の桁数
int digit(ll n) {
    int result = 0;
    while(n > 0){
        n /= 10;
        result++;
    }
    return result;
}

void solve(){
    int N;
    cin >> N;

    vector<ll> A(N);
    for (int i = 0; i < N; i++) {
        cin >> A[i];
    }

    ll ans = 1;
    for (int i = 1; i < N; i++) {
        ll m = pow_10[digit(A[i])];
        ans = lcm(ans, m / gcd(m, A[i]));
    }

    cout << ans << '\n';
}

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

    int T;
    cin >> T;
    while (T--) {
        solve();
    }
    return 0;
}