cheet

def cheet(text, words):
    max_len = max([len(word) for word in words])
    dp = [True] + [False] * len(text)
    for i in range(1, len(text)+1):
        for j in range(1, min(max_len+1, i+1)):
            if dp[i-j]:
                suffix = text[i-j:i]
                if suffix in words:
                    dp[i] = True
                    break
    return dp[-1]


text = input()
n = int(input())
words = set([input() for _ in range(n)])
print('YES' if cheet(text, words) else 'NO')