题解 | 找出字符串中第一个只出现一次的字符

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        char[] chars = sc.nextLine().toCharArray();
        int [] count = new int[200];
        for (int i = 0; i < chars.length; i++) {
            count[chars[i]]++;
        }
        int ans = 0;
        for (int i = 0; i < chars.length; i++) {
            if (count[chars[i]] == 1) {
                System.out.println(chars[i]);
                ans++;
                break;
            }
        }
        if (ans == 0) {
            System.out.println("-1");
        }
    }
}