Here are some challenges you can work on to practice using HashMap:

1. Word Frequency Counter: Write a program that takes a string of text as input and outputs the frequency of each word in the
text. Use a HashMap to store the words and their frequency.

2. Phone Book: Write a program that allows a user to store and look up phone numbers for…Read More

Solution for Character Frequency Counter Challenge :
Topic Used to Implement this challenge : HashMap

Task: Sort the HashMap By Values.
Topic: HashMap

Task: Take a String in LinkedList unless the user puts an integer, Print the index number of vowel in ArrayList.
Programming Language: Java
Topic: ArrayList, LinkedList

Task : Take String as input and print unique characters as string
Topic used to Implement : HashSet

Hello Everyone…!
Task: Ask the user to enter a number until and unless user enter a correct Strong number.
Programming Language:Java

Hello Everyone….!
Task: Ask the user to enter a number until and unless user enter a correct Armstrong number.
Programming Language:Java

Task: Ask the user to enter a number until and unless, user enter a correct factorial number
Programming Language:Java

Hello Everyone….!
Here is the Simple java Program-Alarm