#include <bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
using ll = long long;
vector<int> a;
int n;

void solve(){
    auto b = a;
    sort(a.begin(),a.end());
    for(auto &i:a)i %= 26;
    for(auto &i:a)cout<<(char)('A'+i);
    cout<<endl;
}

signed main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cin >> n;
    a = vector<int>(n);
    for(auto &i:a)cin >> i;
    solve();
}