n = int(input())
words1 = [input() for _ in range(n)]
m = int(input())
words2 = [input() for _ in range(m)]
common_columns = set(words1) & set(words2)
max_length = 0
result = ""
for column in common_columns:
if len(column) > max_length:
max_length = len(column)
result = column
if result:
print(result)
else:
print("-")
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