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

const int N = 1010, INF = 1e8;

int n, m;
int id[N];

int main() {
    cin >> n >> m;
    for (int i = 0; i < n; i++) cin >> id[i];

    while (m--) {
        int l;
        string num;
        cin >> l >> num;
        int res = INF;
        for (int i = 0; i < n; i++) {
            string s = to_string(id[i]);
            if (s.size() >= l && s.substr(s.size() - l) == num)
                res = min(res, id[i]);
        }
        if (res == INF) res = -1;
        cout << res << endl;
    }
    return 0;
}