题解 | #找出字符串中第一个只出现一次的字符#

import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner fzhinput = new Scanner(System.in);
        String zfc = fzhinput.nextLine();
        LinkedHashMap<Character,Integer> tj = new LinkedHashMap<>();
        boolean pd=true;
        for(int i=0;i<zfc.length();i++){
            char c = zfc.charAt(i);
            tj.put(c,tj.getOrDefault(c,0)+1);
        }
        for(int i=0;i<zfc.length();i++){
            char c = zfc.charAt(i);
            if(tj.get(c)==1){
                System.out.println(c);
                pd=false;
                break;
            }
            else{
                pd=true;
            }
        }
        if(pd){
            System.out.println(-1);
        }
    }
}