解法:借用 set 进行集合交运算, 先转换为列表, 再换为集合, 进行交, 再换为列表, 排序, 换为字符串.
# Common Words
def checkio(first, second):
return ','.join(sorted(list(set(first.split(','))&set(second.split(',')))))
#These "asserts" using only for self-checking and not necessary for auto-testing
if __name__ == '__main__':
assert checkio("hello,world", "hello,earth") == "hello", "Hello"
assert checkio("one,two,three", "four,five,six") == "", "Too different"
assert checkio("one,two,three", "four,five,one,two,six,three") == "one,three,two", "1 2 3"
