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…
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…
原题链接在这里:https://leetcode.com/problems/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 = "lovele…
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. 注意事项:您可以假定该字符串只包含小写字母. class Solution { public: int firstUniqChar(string s) { int len = s.size(); map<char, int> check; for(int i = 0;…
1.1 Implement an algorithm to determine if a string has all unique characters. What if you cannot use additional data structure? 这道题让我们判断一个字符串中是否有重复的字符,要求不用特殊的数据结构,这里应该是指哈希表之类的不让用.像普通的整型数组应该还是能用的,这道题的小技巧就是用整型数组来代替哈希表,在之前Bitwise AND of Numbers Range 数…
387. First Unique Character in a String Easy 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…
Description Find the first unique character in a given string. You can assume that there is at least one unique character in the string. Example For "abaccdeff", return 'b'. 解题:返回仅出现一次,并且排在最前面的那个元素,而不是返回第一个不同的元素,一开始理解错了.如果仅仅对于ASCII中的256个字符,可以用数组…
Difficulty:easy More:[目录]LeetCode Java实现 Description https://leetcode.com/problems/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 =…
