题目分析

CCF的第三道题，一般考察的是模拟和文本处理，题目难度不大，但是相当繁琐。按照题目的要求做，需要仔细认真的读题。我使用的是ArrayList解题，看到网上各位大佬使用的方法都是用树作为数据结构，可能这是我代码繁琐和最后出错的原因。

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Scanner;public class Main {class HTMLElement{public String name;public String id;public int layer;public HTMLElement(String name, int layer) {this.name = name;this.layer = layer;this.id = null;}}public HTMLElement getLayers(String string){char[] chars = string.toCharArray();int pointCount = 0;while(chars[pointCount]=='.'){pointCount++;}int layer = pointCount/2;String name = string.substring(pointCount,chars.length).toLowerCase();HTMLElement element = new HTMLElement(name,layer);return element;}public HTMLElement processString(String string){String[] strings = string.split(" ");HTMLElement element = getLayers(strings[0]);if(strings.length==1){return element;}element.id = strings[1];return element;}public ArrayList<Integer> findElements(ArrayList<HTMLElement> elements, String[] strings){ArrayList<Integer> results = new ArrayList<Integer>();int ruleCounter = 0;int layerCounter = 0;boolean isStart = true;int lastCheckIndex = 0;for(int j=0;j<elements.size();j++){HTMLElement curElement = elements.get(j);String s = curElement.name;if(strings[ruleCounter].startsWith("#"))s = curElement.id;if(s!=null&&isStart&&s.equals(strings[ruleCounter])){layerCounter = curElement.layer;ruleCounter++;isStart = false;lastCheckIndex = j;}else if(!isStart&&curElement.layer<layerCounter){ruleCounter = 0;isStart = true;j = lastCheckIndex;}else if(s!=null&&s.equals(strings[ruleCounter])&&curElement.layer>layerCounter){layerCounter = curElement.layer;ruleCounter++;}if(ruleCounter==strings.length){ruleCounter--;if(strings.length==1)isStart = true;if(!results.contains(j+1))results.add(j+1);//j = lastCheckIndex;}}int size = results.size();results.add(0,size);return results;}public void run() {ArrayList<HTMLElement> elements = new ArrayList<HTMLElement>();Scanner in = new Scanner(System.in);String num = in.nextLine();String[] nums = num.split(" ");int htmlLinesNum = Integer.valueOf(nums[0]);int searchNum = Integer.valueOf(nums[1]);for(int i=0;i<htmlLinesNum;i++){try {String line = in.nextLine();HTMLElement element = processString(line);elements.add(element);} catch (Exception e) {e.printStackTrace();}}for(int i=0;i<searchNum;i++){try {String line = in.nextLine();ArrayList<Integer> integers = findElements(elements, line.split(" "));String s = "";for(Integer j:integers){s = s + " "+j.toString();}System.out.println(s);} catch (Exception e) {e.printStackTrace();}}}public static void main(String[] args) {Main main = new Main();main.run();}
}