题解 | #配置文件恢复#

import java.util.*;

public class Main{
    static Map<String, String> map = new HashMap<String, String>(){
        {
            put("reset", "reset what");
            put("reset board", "board fault");
            put("board add", "where to add");
            put("board delete", "no board at all");
            put("reboot backplane", "impossible");
            put("backplane abort", "install first");
        }
    };
    
    public static void main(String []args) {
        Scanner sc = new Scanner(System.in);
        while (sc.hasNext()) {
            String cmd = sc.nextLine();
            calculate(cmd);
        }
    }
    
    public static void calculate(String cmd) {
        String[] cmdArr = cmd.split(" ");
        if (cmdArr.length == 1) {
            if ("reset".contains(cmd)) {
                System.out.println(map.get("reset"));
            } else {
                System.out.println("unknown command");
            }
        } else {
            String result = "unknown command";
            int count = 0;
            for (String key : map.keySet()) {
                if (key.equals(cmd)) {
                    result = map.get(key);
                    break;
                } else {
                    String[] keyArr = key.split(" ");
                    if (keyArr.length > 1 && keyArr[0].indexOf(cmdArr[0]) == 0 && keyArr[1].indexOf(cmdArr[1]) == 0) {
                         result = map.get(key);
                         count++;
                    } 
                }
            }
            System.out.println(count > 1 ? "unknown command" : result);
        }
    }
}