https://leetcode-cn.com/problems/find-common-characters/
给定仅有小写字母组成的字符串数组 A，返回列表中的每个字符串中都显示的全部字符（包括重复字符）组成的列表。例如，如果一个字符在每个字符串中出现 3 次，但不是 4 次，则需要在最终答案中包含该字符 3 次。
你可以按任意顺序返回答案。
示例 1：
输入：["bella","label","roller"]
输出：["e","l","l"]
示例 2：
输入：["cool","lock","cook"]
输出：["c","o"]
提示：
1 <= A.length <= 100
1 <= A[i].length <= 100
A[i][j] 是小写字母
来源：力扣（LeetCode）
链接：https://leetcode-cn.com/problems/find-common-characters
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class Solution: def commonChars(self, l: list) -> list: appearance = {} multi = [] for word in l: appearance[word] = {} for letter in set(word): appearance[word][letter] = word.count(letter) trial = l[0] for letter in trial: flag = True for word, times in appearance.items(): if letter not in times or times[letter] == 0: flag = False break if flag: multi.append(letter) for word, times in appearance.items(): times[letter] -= 1 return multi if __name__ == ‘__main__‘: print(Solution().commonChars([‘bella‘, ‘label‘, ‘roller‘])) print(Solution().commonChars([‘cool‘, ‘lock‘, ‘cook‘]))
原文：https://www.cnblogs.com/noonjuan/p/11041767.html