import sys

def gen_games(i):
    if i == 1:
        yield 'A'
        yield 'B'
    else:
        for game in gen_games(i-1):
            yield 'A' + game
            yield 'B' + game

def shorten(count, l):
    for i in range(count, len(l)):
        if l[:i].count('A') == count or l[:i].count('B') == count:
            return l[:i]
    return l

if __name__=='__main__':
    if len(sys.argv) > 1:
        length = int(sys.argv[1])
        closed = set()
        for game in gen_games(2*length - 1):
            game = shorten(length, game)
            if game not in closed:
                closed.add(game)
                print game