This page contains solutions for all HackerRank Java challenges which were passed successfully. There can be multiple ways of approaching solution to any problem. Please find the provided solutions for learning purposes only.
| Java (Basic) | Java (Intermediate) | Problem Solving (Intermediate) | |
|---|---|---|---|
| Number of Problems | 52 | 2 | 1 |
| Introduction | Strings | BigNumber | Data Structures | Object Oriented Programming | Exception Handling | Advanced | |
|---|---|---|---|---|---|---|---|
| Number of Problems | 13 | 11 | 3 | 15 | 8 | 2 | 12 |
| Sr No | Challenges | Language | Solution | Skills |
|---|---|---|---|---|
| 1 | Welcome to Java! | Java 7 | Welcome-To-Java | Basic |
| 2 | Java Stdin and Stdout I | Java 7 | Java-Stdin-And-Stdout-I | Basic |
| 3 | Java If-Else | Java 7 | Java-If-Else | Basic |
| 4 | Java Stdin and Stdout II | Java 7 | Java-Stdin-And-Stdout-II | Basic |
| 5 | Java Output Formatting | Java 7 | Java-Output-Formatting | Basic |
| 6 | Java Loops I | Java 7 | Java-Loops-I | Basic |
| 7 | Java Loops II | Java 7 | Java-Loops-II | Basic |
| 8 | Java Datatypes | Java 7 | Java-Datatypes | Basic |
| 9 | Java End-of-file | Java 7 | Java-End-of-File | Basic |
| 10 | Java Static Initializer Block | Java 7 | Java-Static-Initializer-Block | Basic |
| 11 | Java Int to String | Java 7 | Java-Int-to-String | Basic |
| 12 | Java Date and Time | Java 7 | Java-Date-and-Time | Basic |
| 13 | Java Currency Formatter | Java 7 | Java-Currency-Formatter | Basic |
| Sr No | Challenges | Language | Solution | Skills |
|---|---|---|---|---|
| 1 | Java Strings Introduction | Java 7 | Java-Strings-Introduction | Basic |
| 2 | Java Substring | Java 7 | Java-Substring | Basic |
| 3 | Java Substring Comparisons | Java 7 | Java-Substring-Comparisons | Basic |
| 4 | Java String Reverse | Java 7 | Java-String-Reverse | Basic |
| 5 | Java Anagrams | Java 7 | Java-Anagrams | Basic |
| 6 | Java String Tokens | Java 7 | Java-String-Tokens | Basic |
| 7 | Pattern Syntax Checker | Java 7 | Pattern-Syntax-Checker | Basic |
| 8 | Java Regex | Java 7 | Java-Regex | Intermediate |
| 9 | Java Regex 2 - Duplicate Words | Java 7 | Java-Regex-2-Duplicate-Words | Basic |
| 10 | Valid Username Regular Expression | Java 7 | Valid-Username-Regular-Expression | Basic |
| 11 | Tag Content Extractor | Java 7 | Tag-Content-Extractor | Basic |
| Sr No | Challenges | Language | Solution | Skills |
|---|---|---|---|---|
| 1 | Java BigDecimal | Java 7 | Java-BigDecimal | Basic |
| 2 | Java Primality Test | Java 7 | Java-Primality-Test | Basic |
| 3 | Java BigInteger | Java 7 | Java-BigInteger | Basic |
| Sr No | Challenges | Language | Solution | Skills |
|---|---|---|---|---|
| 1 | Java Priority Queue | Java 7 | Java Intermediate | |
| 2 | Java 1D Array | Java 7 | Java-1D-Array | Basic |
| 3 | Java 2D Array | Java 7 | Java-2D-Array | Basic |
| 4 | Java Subarray | Java 7 | Java-Subarray | Basic |
| 5 | Java Arraylist | Java 7 | Java-Arraylist | Basic |
| 6 | Java 1D Array (Part 2) | Java 7 | Java-1D-Array-(Part-2) | Basic |
| 7 | Java List | Java 7 | Java-List.sql | Basic |
| 8 | Java Map | Java 7 | Java-Map | Basic |
| 9 | Java Stack | Java 7 | Java-Stack | Basic |
| 10 | Java Hashset | Java 7 | Java-Hashset | Basic |
| 11 | Java Generics | Java 7 | Java-Generics | Basic |
| 12 | Java Comparator | Java 7 | Java-Comparator | Basic |
| 13 | Java Sort | Java 7 | Java-Sort | Basic |
| 14 | Java Dequeue | Java 7 | Java-Dequeue | Problem Solving Intermediate |
| 15 | Java BitSet | Java 7 | Java-BitSet | Basic |
| Sr No | Challenges | Language | Solution | Skills |
|---|---|---|---|---|
| 1 | Java Inheritance I | Java 7 | Java-Inheritance-I | Basic |
| 2 | Java Inheritance II | Java 7 | Java-Inheritance-II | Basic |
| 3 | Java Abstract Class | Java 7 | Java-Abstract-Class | Basic |
| 4 | Java Interface | Java 7 | Java-Interface | Basic |
| 5 | Java Method Overriding | Java 7 | Java-Method-Overriding | Basic |
| 6 | Java Method Overriding 2 (Super Keyword) | Java 7 | Java-Method-Overriding-2-(Super-Keyword) | Basic |
| 7 | Java Instanceof keyword | Java 7 | Java-Instanceof-keyword | Basic |
| 8 | Java Iterator | Java 7 | Java-Iterator | Basic |
| Sr No | Challenges | Language | Solution | Skills |
|---|---|---|---|---|
| 1 | Java Exception Handling (Try-catch) | Java 7 | Java-Exception-Handling-(Try-catch) | Basic |
| 2 | Java Exception Handling | Java 7 | Java-Exception-Handling | Basic |
| Sr No | Challenges | Language | Solution | Skills |
|---|---|---|---|---|
| 1 | Java Visitor Pattern | Java 7 | Java-Visitor-Pattern | Advanced |
| 2 | Java Varargs - Simple Addition | Java 7 | Java-Varargs-Simple-Addition | Basic |
| 3 | Java Reflection - Attributes | Java 7 | Java-Reflection-Attributes | Basic |
| 4 | Can You Access? | Java 7 | Can-You-Access | Advanced |
| 5 | Prime Checker | Java 7 | Prime-Checker | Basic |
| 6 | Java Factory Pattern | Java 7 | Java-Factory-Pattern | Basic |
| 7 | Java Singleton Pattern | Java 7 | Java-Singleton-Pattern | Basic |
| 8 | Java Annotations | Java 7 | Java-Annotations | Advanced |
| 9 | Covariant Return Types | Java 7 | Covariant-Return-Types | Advanced |
| 10 | Java Lambda Expressions | Java 7 | Java-Lambda-Expressions | Advanced |
| 11 | Java MD5 | Java 7 | Java-MD5 | Advanced |
| 12 | Java SHA-256 | Java 7 | Java-SHA-256 | Advanced |