A collection of Java utility programs to demonstrate problem-solving techniques for strings, arrays, and basic programming challenges. Ideal for practice or as references for coding interviews.

Skills Gained:

• String Manipulation
• Array Processing
• Character Frequency Analysis
• Handling Special Characters
• Substring Generation
• Sorting and Reordering Elements
• Iterative Problem Solving
• Debugging Java Programs
• Optimizing Algorithms
• Modular Code Design

Key Files and Descriptions

• ReverseString.java: Reverses a given string character by character.
  Example: Hello World → dlroW olleH

• ChangeSpecialCharacter.java: Replaces a specific special character with another.
  Example: Hello @Japneet → Hello _Japneet

• ReverseSentence.java: Reverses the order of words in a sentence.
  Example: Hello I am Japneet → Japneet am I Hello

• FindFirstNonRepeatedCharacter.java: Finds the first non-repeated character in a string.
  Example: swiss → w

• RemoveAllSpecialCharacters.java: Removes all special characters from a string.
  Example: Hello^^%#$(!)_+ J@apneet → Hello Japneet

• RemoveDuplicateWordsFromSentence.java: Removes duplicate words in a sentence.
  Example: Hello I am Japneet Japneet am → Japneet am

• RemoveWhiteSpaces.java: Removes all white spaces from a string.
  Example: Hello Japneet → HelloJapneet

• MoveNegativeNumbersToStart.java: Moves all negative numbers to the beginning of an array.
  Example: [-1, 2, 3, -4, -7, 8] → [-1, -4, -7, 2, 3, 8]

• FindRepeatingElements.java: Identifies elements that repeat in an array and their counts.
  Example: [4, 2, 3, 5, 1, 2, 4] → 4: 2 times, 2: 2 times

• ExtractLast4CharactersOfString.java: Extracts the last 4 characters of a string.
  Example: swiss → wiss

• FindMaximumDifference.java: Finds the maximum difference between the largest and smallest elements in an array.
  Example: [10, 90, 2, 40, 1, 25] → 89

• ReverseEachWord.java: Reverses each word in a string.
  Example: Hello World → olleH dlroW

• PrintAllTheSubstrings.java: Prints all substrings of a string.
  Example: abc → a, ab, abc, b, bc, c

• FindLargestSmallestAnd2ndLargest.java: Finds the largest, smallest, and second-largest numbers in an array.
  Example: [23, 5, 1, 89, 65] → Largest: 89, 2nd Largest: 65, Smallest: 1

• PrintFirstLetterOfString.java: Extracts and prints the first letter of each word in a string.
  Example: Hello I am Japneet → H I a J

• PrintWordsVowelsFrequencyofeachCharacter.java: Prints the total word count, count of vowels, and frequency of each character.