使用数组查找包含在2个java文本文件中的唯一单词列表

Question

我需要读取两个文本文件并显示两个文本文件中的所有唯一单词。（两个文件中的单词只能打印一次）

文件1.txt

狮

老虎

猎豹

大象

奶牛

file2.txt

老鼠

狗

奶牛

猫

狮

预期产出:

狮子老虎猎豹大象奶牛狗猫老鼠

public class Workshop {

static int count1 = 0;
static int count2 = 0;

private static final String FILE1 = "C:\\Users\\shagi\\Desktop\\file1.txt";
private static final String FILE2 = "C:\\Users\\shagi\\Desktop\\file2.txt";

static String arrayLines1[] = new String[countLines(FILE1)];
static String arrayLines2[] = new String[countLines(FILE2)];
static String totalArray[] = new String[arrayLines1.length + arrayLines2.length];
static String arrayLines1new[]=new String[countLines(FILE1)];
static int flag = 0;
static int k=arrayLines1.length;

public static void main(String[] args) throws IOException {
    readFile(FILE1, FILE2);
    displaySimilar();
    displayAll();
}

public static int countLines(String File) {
    int lineCount = 0;
    try {
        BufferedReader br = new BufferedReader(new FileReader(File));
        while ((br.readLine()) != null) {
            lineCount++;
        }
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
    return lineCount;
}

public static void readFile(String File1, String File2) {
    String contents1 = null;
    String contents2 = null;
    try {
        FileReader file1 = new FileReader(File1);
        FileReader file2 = new FileReader(File2);
        BufferedReader buf1 = new BufferedReader(file1);
        BufferedReader buf2 = new BufferedReader(file2);
        while ((contents1 = buf1.readLine()) != null) {
            arrayLines1[count1] = contents1;
            count1++;
        }
        while ((contents2 = buf2.readLine()) != null) {
            arrayLines2[count2] = contents2;
            count2++;
        }
    } catch (Exception e) {
        e.printStackTrace();
    }
}

有两种方法，我试图找到我的问题的答案方法1

public static void displayAll() {
    for (int i =0; i<k-1;i++){
        System.out.println(totalArray[i]);
    }

    System.out.println(totalArray[k-1]);
    System.out.println("");
    int p=0;
    for (int i=0;i<arrayLines2.length;i++){
        for (int j=0;j<arrayLines1.length;j++){
            if (arrayLines2[i].equals(arrayLines1[j])){
                flag=1;
                break;
            } else {
                flag=0;
            }
            if (flag==1){
                arrayLines1new[p]=arrayLines2[i];
                p++;
            }
        }
    }

方法2

 public static void displayAll() {
    for (int i=0;i<arrayLines1.length;i++){
        String a=arrayLines1[i];
        for (int j=0;j<arrayLines2.length;j++){
            String b =arrayLines2[j];
            if (!a.equals(b)){
                System.out.println(a);
            }
        }
    }
 }

但两者都没有给出预期的输出。

Answer 1

对于哈希映射来说，这将是一个很好的情况。键将是单词，值将是出现次数。然后，您可以打印出值为 1 的密钥。伪代码如下所示：

1. 初始化映射：哈希映射

您还可以使用两个arrayList完成相同的任务，一个用来跟踪单词，另一个用来记录计数。

这两种方法的时间复杂度都是O(N ),但是使用map更有效，因为map的值可以在O(1)中更新。

Answer 2

有很多冗余代码。这是一个更简单、更短的版本。

我正在使用Set及其操作来查找常见（交集）、不常见和所有唯一的单词。

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.util.HashSet;
import java.util.Set;

public class Workshop {

    private static final String FILE1 = "C:\\Users\\shagi\\Desktop\\file1.txt";
    private static final String FILE2 = "C:\\Users\\shagi\\Desktop\\file2.txt";

    static Set<String> file1Words = new HashSet<String>();
    static Set<String> file2Words = new HashSet<String>();
    static Set<String> allWords = new HashSet<String>();
    static Set<String> commonWords = new HashSet<String>();
   static Set<String> uncommonWords = new HashSet<String>();

    public static void main(String[] args) throws IOException {
        file1Words.addAll(readFile(FILE1));
        file2Words.addAll(readFile(FILE2));
        System.out.println("file1  : " + file1Words);
        System.out.println("file2  : " + file2Words);
        displaySimilar();
        System.out.println("common : " + commonWords);
        displayAll();
        System.out.println("all    : " + allWords);
         displayUnCommon();
        System.out.println("uncommon : " + uncommonWords);
    }

    public static void displaySimilar() {
        commonWords.addAll(file1Words);
        commonWords.retainAll(file2Words);
    }

    public static void displayUnCommon() {
         uncommonWords.addAll(file1Words);
        uncommonWords.addAll(file2Words);
        uncommonWords.removeAll(commonWords);
    }

   public static Set<String> readFile(String file) {
        Set<String> words = new HashSet<String>();
        try {
            FileReader fileReader = new FileReader(file);
            BufferedReader buffer = new BufferedReader(fileReader);
            String content = null;
            while ((content = buffer.readLine()) != null) {
                words.add(content);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return words;
    }

    public static void displayAll() {
        allWords.addAll(file1Words);
        allWords.addAll(file2Words);
    }
}

示例运行：

file1  : [lion, cheetah, tiger, elephant, cow]
file2  : [lion, mouse, cat, cow, dog]
common : [lion, cow]
all    : [cheetah, lion, cat, mouse, tiger, elephant, cow, dog]
uncommon : [cheetah, cat, mouse, tiger, elephant, dog]