题解 | #记票统计#

import java.util.HashMap;
import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        // 注意 hasNext 和 hasNextLine 的区别
        while (in.hasNext()) { // 注意 while 处理多个 case
            int n1 = in.nextInt();
            in.nextLine(); //指针移到下一行开头
            String[] candidate = in.nextLine().split(" ");
            int n2 = in.nextInt();
            in.nextLine(); //指针移到下一行开头
            String[] vote = in.nextLine().split(" ");
            
            HashMap<String, Integer> map = new HashMap<>();
            for(String s: candidate){
                map.put(s, 0);
            }
            int invalid = 0;
            for(String s: vote){
                if(!map.containsKey(s)) invalid++;
                else map.put(s, map.get(s) + 1);
            }

            StringBuilder sb = new StringBuilder();
            for(String s: candidate){
                sb.append(s);
                sb.append(" : ");
                sb.append(map.get(s));
                sb.append("\n");
            }
            sb.append("Invalid : " + invalid);
            System.out.print(sb);
        }
    }
}