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

typedef long long ll;
typedef long double ld;

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    string a = "";
    for (int i = 0; i < 10; i++) a += ('0' + i);
    for (int i = 0; i < 26; i++) a += ('A' + i);
    for (int i = 0; i < 26; i++) a += ('a' + i);
    map<char, ll> m;
    for (int i = 0; i < a.size(); i++)
        m[a[i]] = i;

    ll b, n;
    cin >> b >> n;
    while (n--) {
        ll k;
        cin >> k;
        ll lo[k] = {};
        ll hi[k] = {};
        fill_n(hi, k, b - 1);
        vector<pair<string, string>> v;
        string s, t;
        bool valid = true;
        while (true) {
            bool done = true;
            for (int i = 0; i < k; i++)
                done &= lo[i] == hi[i];
            if (done)
                break;
            for (int i = 0; i < k; i++)
                done |= lo[i] > hi[i];
            if (done) {
                cout << "cheater" << endl;
                cin >> s;
                goto next;
            }
            ll mid[k] = {};
            t = "";
            for (int i = 0; i < k; i++) {
                mid[i] = (lo[i] + hi[i]) / 2;
                t += a[mid[i]];
            }
            cout << t << endl;
            cin >> s;
            if (s == "correct")
                goto next;
            v.push_back({t, s});
            for (int i = 0; i < k; i++) {
                if (s[i] == '=') {
                    lo[i] = mid[i];
                    hi[i] = mid[i];
                } else if (s[i] == '+') {
                    lo[i] = mid[i] + 1;
                } else {
                    hi[i] = mid[i] - 1;
                }
            }
        }
        t = "";
        for (int i = 0; i < k; i++)
            t += a[lo[i]];
        cout << t << endl;
        cin >> s;
        if (s != "correct") {
            cout << "cheater" << endl;
            cin >> s;
        }
        next: continue;
    }
}