1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
#include <bits/stdc++.h>

#define ll long long
#define str string
#define pii pair<int, int>
#define pll pair<ll, ll>
#define fi first
#define se second

#define vc vector<char>
#define vvc vector<vc>
#define vi vector<int>
#define vvi vector<vi>
#define vvvi vector<vvi>
#define vvvvi vector<vvvi>
#define vll vector<ll>
#define vvll vector<vll>
#define vvvll vector<vvll>
#define vvvvll vector<vvvll>
#define vs vector<str>
#define vvs vector<vs>
#define vpii vector<pii>
#define vvpii vector<vpii>
#define vpll vector<pll>
#define vvpll vector<vpll>
#define vb vector<bool>
#define vvb vector<vb>
#define rep(i, a, b) for (int i = (a); i < int(b); i++)
#define repi(i, a, b) for (int i = (a); i <= int(b); i++)

using namespace std;


void solve() {
    int n; cin >> n;
    str s;
    cin >> s;
    int cnt1 = 0, cnt0 = 0;
    rep(i, 0, 8 * n) {
        if (s[i] == '1')
            cnt1++;
        else
            cnt0++;
    }

    if (abs(cnt1 - cnt0) % 2 == 1) {
        cout << "NIE";
        return;
    }

    str ans;

    //cerr << cnt1 << " " << cnt0 << endl;

    if (cnt1 > cnt0) {
        if (cnt1 - cnt0 > 4 * n) {
            cout << "NIE";
            return;
        }

        while (ans.size() < n && cnt1 - cnt0 > 3) {
            ans.push_back('o');
            cnt1 -= 6;
            cnt0 -= 2;
        }

        while (ans.size() < n && cnt1 - cnt0 > 0) {
            ans.push_back('n');
            cnt1 -= 5;
            cnt0 -= 3;
        }

        while (ans.size() < n) {
            ans.push_back('c');
        }
    }
    else {
        if (cnt0 - cnt1 > 2 * n) {
            cout << "NIE";
            return;
        }

        while (ans.size() < n && cnt0 - cnt1 > 0) {
            ans.push_back('a');
            cnt0 -= 5;
            cnt1 -= 3;
        }

        while (ans.size() < n) {
            ans.push_back('c');
        }
    }

    cout << ans;
}


int main() {

    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    bool _multipleTestCases = false;

    if (_multipleTestCases) {
        ll t; cin >> t;
        while (t--)
            solve();
    }
    else {
        solve();
    }

    return 0;
}