54.字符流中第一个不重复的字符(python)

 1 class Solution:
 2     # 返回对应char
 3     def __init__(self):
 4         self.stack=[]
 5     def FirstAppearingOnce(self):
 6         # write code here
 7         for e in self.stack:
 8             if self.stack.count(e)==1:
 9                 return e
10         return "#"
11     def Insert(self, char):
12         # write code here
13         self.stack.append(char)