from itertools import product


def main():
    l = int(input())
    n = int(input())
    dnas = set()
    for s in input().split():
        k = set(["".join(x) + s for x in product("AB", repeat=l - len(s))])
        dnas.update(k)
    print(len(dnas))
    
if __name__ == '__main__':
    main()