// #include <bits/allocator.h> // Temp fix for gcc13 global pragma
// #pragma GCC target("avx2,bmi2,popcnt,lzcnt")
// #pragma GCC optimize("O3,unroll-loops")
#include <bits/stdc++.h>
// #include <x86intrin.h>
using namespace std;
#if __cplusplus >= 202002L
using namespace numbers;
#endif
#ifdef LOCAL
	#include "Debug.h"
#else
	#define debug_endl() 42
	#define debug(...) 42
	#define debug2(...) 42
	#define debug_bin(...) 42
#endif



int main(){
	cin.tie(0)->sync_with_stdio(0);
	cin.exceptions(ios::badbit | ios::failbit);
	int n;
	cin >> n;
	vector<array<int, 2>> a;
	for(auto i = 0; i < n; ++ i){
		int x;
		cin >> x;
		a.push_back({x / 26, x % 26});
	}
	ranges::sort(a);
	for(auto c: a | ranges::views::values){
		cout << char(c + 'A');
	}
	cout << "\n";
	return 0;
}

/*

*/