HackerRank Tag Content Extractor solution in java

In this HackerRank Tag Content Extractor problem in the java programming language you have Given a string of text in a tag-based language, parse this text and retrieve the contents enclosed within sequences of well-organized tags meeting the following criterion:

1. The name of the start and end tags must be the same. The HTML code <h1>Hello World</h2> is not valid, because the text starts with an h1 tag and ends with a non-matching h2 tag.
2. Tags can be nested, but content between nested tags is considered not valid. For example, in <h1><a>contents</a>invalid</h1>, contents is valid but invalid is not valid.
3. Tags can consist of any printable characters.

HackerRank Tag content extractor problem solution in java programming.

import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution{
    
   public static void main(String[] args){
      Scanner in = new Scanner(System.in);
      int t = Integer.parseInt(in.nextLine());
      
      while(t-->0){
          String line = in.nextLine();
         
          Matcher m = Pattern.compile("<(.+)>(([^<>]+))</\1>").matcher(line);
          
          if (!m.find()) {
              System.out.println("None");
              continue;
          }
          
          m.reset();
          while (m.find()){
              System.out.println(m.group(2));
          }
       }
    }
 }

Second solution

import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution{
   public static void main(String[] args){
       
      String regex = "<([^<>]+)>([^<>]+)</\1>";
      Pattern pattern = Pattern.compile(regex);
      
      Scanner in = new Scanner(System.in);
      int testCases = Integer.parseInt(in.nextLine());
      while(testCases>0){
         String line = in.nextLine();
         Matcher matcher = pattern.matcher(line);
         int counter = 0;
         while (matcher.find()) {
             System.out.println(matcher.group(2));
             counter++;
         }
         if (counter == 0) System.out.println("None");
         testCases--;
      }
   }
}

A solution in java8 programming.

import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/* Solution assumes we can't have the symbol "<" as text between tags */
public class Solution{
    public static void main(String[] args){
        Scanner scan = new Scanner(System.in);
        int testCases = Integer.parseInt(scan.nextLine());
        
        while (testCases-- > 0) {
            String line = scan.nextLine();
            
            boolean matchFound = false;
            Pattern r = Pattern.compile("<(.+)>([^<]+)</\1>");
            Matcher m = r.matcher(line);

            while (m.find()) {
                System.out.println(m.group(2));
                matchFound = true;
            }
            if ( ! matchFound) {
                System.out.println("None");
            }
        }
    }
}