python-leetcode题解之第1002题查找共用字符.zip

''' Given an array A of strings made only from lowercase letters, return a list of all characters that show up in all strings within the list (including duplicates). For example, if a character occurs 3 times in all strings but not 4 times, you need to include that character three times in the final answer. You may return the answer in any order. Example 1: Input: ["bella","label","roller"] Output: ["e","l","l"] Example 2: Input: ["cool","lock","cook"] Output: ["c","o"] ''' class Solution(object): def commonChars(self, A): """ :type A: List[str] :rtype: List[str] """ char_map = {} for char in A[0]: if char in char_map: char_map[char] += 1 else: char_map[char] = 1 int_map = {} for index in range(1, len(A)): for char in char_map.keys(): if char in A[index]: char_count = min(A[index].count(char), char_map[char]) char_map[char] = char_count else: del char_map[char] result = [] for key, value in char_map.items(): result.extend([key]*value) return result