LeetCode--387--字符串中的第一个唯一字符

问题描述：

给定一个字符串，找到它的第一个不重复的字符，并返回它的索引。如果不存在，则返回 -1。

案例:

s = "leetcode"
返回 0.

s = "loveleetcode",
返回 2.

方法：

class Solution(object):
    def firstUniqChar(self, s):
        """
        :type s: str
        :rtype: int
        """
        x = "abcdefghijklmnopqrstuvwxyz"
        res = []  #res=[s.index[i] for i in x if s.count(i) == 1]
        for i in x:
            if i in s and s.count(i) == 1:
                res.append(s.index(i))
        if len(res):
            return min(res)
        return -1

官方：

class Solution(object):
    def firstUniqChar(self, s):
        """
        :type s: str
        :rtype: int
        """
        
        if s == '':
            return -1
        
        l = len(s)
        tmp = l
        for i in 'abcdefghijklmnopqrstuvwxyz':
            start = s.find(i)
            end = s.rfind(i)
            if start != -1 and start == end:
                tmp = min(tmp, start)
        if tmp < l:
            return tmp
        else:
            return -1

2018-09-28 16:27:05