题目
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.
解题思路
代码
class Solution:
def commonChars(self, A: List[str]) -> List[str]:
ct = Counter(A[0])
for w in A[1:]:
tmp = Counter(w)
for key in list(ct.keys()):
if key not in tmp:
del ct[key]
else:
ct[key] = min(ct[key], tmp[key])
res = []
for key in ct:
res += [key] * ct[key]
return res
