def solve(n, D):
    original = [num % 26 for num in D]
    alpha = {
        0: 'A', 1: 'B', 2: 'C', 3: 'D', 4: 'E', 5: 'F', 6: 'G', 7: 'H',
        8: 'I', 9: 'J', 10: 'K', 11: 'L', 12: 'M', 13: 'N', 14: 'O', 15: 'P',
        16: 'Q', 17: 'R', 18: 'S', 19: 'T', 20: 'U', 21: 'V', 22: 'W', 23: 'X',
        24: 'Y', 25: 'Z'
    }

    B = [(num - (num % 26)) // 26 for num in D]

    sortedB = [(i, b) for i, b in enumerate(B)]

    sortedB.sort(key=lambda x: x[1])

    original_positions = [pair[0] for pair in sortedB]

    decrypt = ''.join([alpha[original[pos]] for pos in original_positions])

    return decrypt


n = int(input())
D = list(map(int, input().split()))


decrypted_message = solve(n, D)
print(decrypted_message)