HackerRank Java Solutions

A repository containing structured descriptions and Java solutions to HackerRank Java practice challenges.

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Problem Set & Solutions

Here is the list of problems resolved in this repository:

Problem ID	Title	Description	Challenge Link	Solution	Difficulty
0001	Java Stdin and Stdout II	problem_0001.md	HackerRank	Solution.java	Easy
0002	Welcome to Java!	problem_0002.md	HackerRank	Solution.java	Easy
0003	Java Stdin and Stdout I	problem_0003.md	HackerRank	Solution.java	Easy
0004	Java If-Else	problem_0004.md	HackerRank	Solution.java	Easy
0005	Java Output Formatting	problem_0005.md	HackerRank	Solution.java	Easy
0006	Java Loops I	problem_0006.md	HackerRank	Solution.java	Easy
0007	Java Datatypes	problem_0007.md	HackerRank	Solution.java	Easy
0008	Java Loops II	problem_0008.md	HackerRank	Solution.java	Easy
0009	Java End-of-file	problem_0009.md	HackerRank	Solution.java	Easy
0010	Java Static Initializer Block	problem_0010.md	HackerRank	Solution.java	Easy
0011	Java Int to String	problem_0011.md	HackerRank	Solution.java	Easy
0012	Java Date and Time	problem_0012.md	HackerRank	Solution.java	Easy
0013	Java Currency Formatter	problem_0013.md	HackerRank	Solution.java	Easy
0014	Java Varargs - Simple Addition	problem_0014.md	HackerRank	Solution.java	Easy
0015	Java Strings Introduction	problem_0015.md	HackerRank	Solution.java	Easy
0016	Java Substring	problem_0016.md	HackerRank	Solution.java	Easy
0017	Java Substring Comparisons	problem_0017.md	HackerRank	Solution.java	Easy
0018	Java String Reverse	problem_0018.md	HackerRank	Solution.java	Easy
0019	Java Anagrams	problem_0019.md	HackerRank	Solution.java	Easy
0020	Java String Tokens	problem_0020.md	HackerRank	Solution.java	Easy
0021	Pattern Syntax Checker	problem_0021.md	HackerRank	Solution.java	Easy
0022	Java Regex	problem_0022.md	HackerRank	Solution.java	Medium
0023	Java SHA-256	problem_0023.md	HackerRank	Solution.java	Easy
0024	Java Inheritance I	problem_0024.md	HackerRank	Solution.java	Easy
0025	Java Inheritance II	problem_0025.md	HackerRank	Solution.java	Easy
0026	Java MD5	problem_0026.md	HackerRank	Solution.java	Easy
0027	Java 1D Array	problem_0027.md	HackerRank	Solution.java	Easy
0028	Java 2D Array	problem_0028.md	HackerRank	Solution.java	Easy

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Project Structure

The project is structured as follows:

HackerRank/
├── problems/                  # Markdown files containing problem statements
│   ├── problem_0001.md
│   ├── problem_0002.md
│   ├── problem_0003.md
│   ├── problem_0004.md
│   ├── problem_0005.md
│   ├── problem_0006.md
│   ├── problem_0007.md
│   ├── problem_0008.md
│   ├── problem_0009.md
│   ├── problem_0010.md
│   ├── problem_0011.md
│   ├── problem_0012.md
│   ├── problem_0013.md
│   ├── problem_0014.md
│   ├── problem_0015.md
│   ├── problem_0016.md
│   ├── problem_0017.md
│   ├── problem_0018.md
│   ├── problem_0019.md
│   ├── problem_0020.md
│   ├── problem_0021.md
│   ├── problem_0022.md
│   ├── problem_0023.md
│   ├── problem_0024.md
│   ├── problem_0025.md
│   ├── problem_0026.md
│   ├── problem_0027.md
│   └── problem_0028.md
├── src/main/java/             # Java solution implementations
│   ├── problem_0001/Solution.java
│   ├── problem_0002/Solution.java
│   ├── problem_0003/Solution.java
│   ├── problem_0004/Solution.java
│   ├── problem_0005/Solution.java
│   ├── problem_0006/Solution.java
│   ├── problem_0007/Solution.java
│   ├── problem_0008/Solution.java
│   ├── problem_0009/Solution.java
│   ├── problem_0010/Solution.java
│   ├── problem_0011/Solution.java
│   ├── problem_0012/Solution.java
│   ├── problem_0013/Solution.java
│   ├── problem_0014/Solution.java
│   ├── problem_0015/Solution.java
│   ├── problem_0016/Solution.java
│   ├── problem_0017/Solution.java
│   ├── problem_0018/Solution.java
│   ├── problem_0019/Solution.java
│   ├── problem_0020/Solution.java
│   ├── problem_0021/Solution.java
│   ├── problem_0022/Solution.java
│   ├── problem_0023/Solution.java
│   ├── problem_0024/Solution.java
│   ├── problem_0025/Solution.java
│   ├── problem_0026/Solution.java
│   ├── problem_0027/Solution.java
│   └── problem_0028/Solution.java
└── README.md                  # Main overview of the repository

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How to Run the Solutions

To compile and run any of the solutions locally:

1. Navigate to the root directory of the project.
2. Compile the Java file using javac:

   javac src/main/java/problem_<ID>/Solution.java -d target/classes

3. Run the compiled class using java (providing input if needed):

   java -cp target/classes problem_<ID>.Solution

   Example for Problem 0001:

   java -cp target/classes problem_0001.Solution