Beginner Projects

Build these on your own using what you learned in Level 1. Each one uses variables, strings, lists, maps, loops, methods, and closures.

1. Number Guessing Game

Pick a random number from 1 to 100 with new Random().nextInt(100) + 1, read guesses with System.in.newReader().readLine(), say "higher" or "lower", and count the attempts. Handle input that isn't a number with isInteger().

2. To-Do List

Keep tasks in a list of maps ([title: ..., done: false]). Support commands to add, complete, remove, and list tasks, printing them numbered with eachWithIndex.

3. Word Frequency Counter

Read a paragraph, split it into words with tokenize, count them in a map, and print the ten most common words, sorted by count.

4. Grade Book

Store students as maps with a name and a list of scores, compute each average with sum() and size(), assign a letter grade with a switch over ranges, and print an aligned report with padRight.

5. Unit Converter

Write methods that convert between Celsius and Fahrenheit, kilometers and miles, and kilograms and pounds. Print a conversion table using ranges and BigDecimal rounding.