JZ54 字符流中第一个不重复的字符
字符流中第一个不重复的字符
https://www.nowcoder.com/practice/00de97733b8e4f97a3fb5c680ee10720?tpId=13&&tqId=11207&rp=1&ru=/ta/coding-interviews&qru=/ta/coding-interviews/question-ranking
linkedhaspmap
可以
import java.util.*; public class Solution { LinkedHashMap<Character,Integer> map = new LinkedHashMap<>(); public void Insert(char ch) { if(map.containsKey(ch)) { map.put(ch,-1); } else { map.put(ch, 1); } } public char FirstAppearingOnce() { Iterator<Character> iterator = map.keySet().iterator(); while (iterator.hasNext()) { char cur = iterator.next(); if(map.get(cur) == 1) { return cur; } } return '#'; } }