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

#define fast_io ios::sync_with_stdio(0); cin.tie(0); cout.tie(0)

#define int long long
#define pb push_back
#define endl '\n'

const int INF = 1e18;

int ans;

void generate(string cur, int len, vector<int>& d, int target) {
    if ((int)cur.size() == len) {
        if (cur[0] == '0') return;

        int num = stoll(cur);
        ans = min(ans, abs(target - num));
        return;
    }

    for (int x : d) {
        generate(cur + char(x + '0'), len, d, target);
    }
}

void solve() {

    int a, n;
    cin >> a >> n;

    vector<int> b(n);

    for (int i = 0; i < n; i++) cin >> b[i];

    int digits = to_string(a).size();

    ans = INF;

    generate("", digits, b, a);

    if (digits > 1)
        generate("", digits - 1, b, a);

    generate("", digits + 1, b, a);

    cout << ans << endl;
}

int32_t main() {

    fast_io;

    int t;
    cin >> t;

    while (t--) solve();

    return 0;
}