Description

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

Example

s = “leetcode” return 0.

s = “loveleetcode”, return 2.

Note:

You may assume the string contain only lowercase letters.

Code

class Solution(object): def firstUniqChar(self, s): """ :type s: str :rtype: int """ cnt = dict() for i in s: cnt[i] = cnt.get(i, 0) + 1 for i,x in enumerate(s): if cnt[x] == 1: return i else: return -1