// -*- coding:utf-8-unix -*-

fn main() {
    input! {
        t: usize,
    }
    for _ in 0..t {
        input! {
            n: usize,
            a: [u32; n],
        }
        let mut res = 1u64;
        for &ae in &a[1..] {
            let t = 10u64.pow(ae.to_string().len() as u32);
            let b = t / t.gcd(&(ae as u64));
            res = res.lcm(&b);
        }
        println!("{}", res);
    }
}

#[allow(unused_imports)]
use {
    itertools::*,
    num::*,
    proconio::input,
    std::{
        cmp::*,
        collections::*,
        io::{BufReader, BufWriter, Write, stderr, stdin, stdout},
    },
};

#[allow(dead_code)]
trait Change {
    fn chmax(&mut self, x: Self);
    fn chmin(&mut self, x: Self);
}
impl<T: PartialOrd> Change for T {
    fn chmax(&mut self, x: T) {
        if *self < x {
            *self = x;
        }
    }
    fn chmin(&mut self, x: T) {
        if *self > x {
            *self = x;
        }
    }
}