First Unique Character in a String

Given a string, find the first non-repeating character in it and return it's index. If it doesn't exist, return -1. Examples:

s = "leetcode"
return 0.
s = "loveleetcode",
return 2.

Note: You may assume the string contain only lowercase letters.

1. 用一个新的list存index和同样字母出现的次数

   class Solution(object):
    def firstUniqChar(self, s):
        """
        :type s: str
        :rtype: int
        """
        indexes = [0] * len(s)
        for i in range(len(s)):
            indexes[s.index(s[i])] += 1
        for i in range(len(indexes)):
            if indexes[i] == 1:
                return i
        return -1
   

2. 有左右find确认出现的次数

   class Solution(object):
    def firstUniqChar(self, str1):
        """
        :type s: str
        :rtype: int
        """
        for x in str1:
            if str1.find(x)==str1.rfind(x):
                return str1.find(x)
        return -1
   

Note: 只有string才有rfind/rindex。