[leetCode刷题笔记]387. First Unique Character in a String

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从今天开始，刷题慢工细作！

HashMap解法

public class Solution {    public int firstUniqChar(String s) {        Map<Character, Integer> charMap = new HashMap<Character, Integer>();        for (int i = 0; i < s.length(); i++) {            char curChar = s.charAt(i);            if (charMap.containsKey(curChar)) {                charMap.put(curChar, charMap.get(curChar) + 1);            }            else {                                charMap.put(curChar, 1);            }                    }        for (int i = 0; i < s.length(); i++) {            char curChar = s.charAt(i);            if (charMap.get(curChar) == 1) {                return i;            }        }        return -1;    }}

第二种解法，用array

public class Solution {    public int firstUniqChar(String s) {        int[] charArray = new int[26];                for (int i = 0; i < s.length(); i++) {            char cur = s.charAt(i);            charArray[cur - 'a']++;        }         for (int i = 0; i < s.length(); i++) {            char cur = s.charAt(i);            if (charArray[cur - 'a'] == 1) {                return i;            }        }        return -1;    }}

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