题解 | #配置文件恢复#

import java.util.*;

public class Main {

private static final Map<String, List<String>> MATCH_MAP = new HashMap<>();

static {
    MATCH_MAP.put("r", Collections.singletonList("reset" + "#" + "reset what"));
    List<String> rBList = new ArrayList<>();
    rBList.add("reset board" + "#" + "board fault");
    rBList.add("reboot backplane" + "#" + "impossible");
    MATCH_MAP.put("r,b", rBList);

    List<String> bAList = new ArrayList<>();
    bAList.add("board add" + "#" + "where to add");
    bAList.add("backplane abort" + "#" + "install first");
    MATCH_MAP.put("b,a", bAList);
    MATCH_MAP.put("b,d", Collections.singletonList("board delete" + "#" +
                  "no board at all"));
}

public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    while (sc.hasNext()) {
        String[] strings = sc.nextLine().split(" ");
        StringBuilder sb = new StringBuilder();
        if (strings.length == 1) {
            sb.append(strings[0].charAt(0));
        } else {
            sb.append(strings[0].charAt(0)).append(",").append(strings[1].charAt(0));
        }

        if (Objects.isNull(MATCH_MAP.get(sb.toString()))) {
            System.out.println("unknown command");
        } else {
            List<String> list = MATCH_MAP.get(sb.toString());
            int count = 0;
            String result = "unknown command";
            for (String s : list) {
                String[] matchStr = s.split("#");
                String[] strings1 = matchStr[0].split(" ");
                boolean matchFlag = false;
                if (strings.length == 1) {
                    String sub = strings1[0].substring(0, Math.min(strings1[0].length(),
                                                       strings[0].length()));
                    if (strings[0].equals(sub)) {
                        matchFlag = true;
                        result = matchStr[1];
                    }
                } else {
                    String sub = strings1[0].substring(0, Math.min(strings1[0].length(),
                                                       strings[0].length()));
                    String sub1 = strings1[1].substring(0, Math.min(strings1[1].length(),
                                                        strings[1].length()));
                    if (strings[0].equals(sub) && strings[1].equals(sub1)) {
                        matchFlag = true;
                        result = matchStr[1];
                    }
                }

                if (matchFlag) {
                    count++;
                }
            }
            if (count > 1) {
                System.out.println("unknown command");
            } else {
                System.out.println(result);
            }
        }
    }
}

}