LeetCode 387. First Unique Character in a String

题目

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.

思路

Easy题打卡。

代码

class Solution(object):
    def firstUniqChar(self, s):
        """
        :type s: str
        :rtype: int
        """
        dic = {}
        for i in s:
            if i in dic:
                dic[i] += 1
            else:
                dic[i] = 1
        for i in range(len(s)):
            if dic[s[i]] == 1:
                return i
        return -1