Java from zero
From your first line of code to solving DSA problems in Java.
- 00
Set up your computer
Install Java and VS Code, and run your first program on your own machine.
- 01
Your first program
What a Java program looks like, how it runs, and how to print.
- 02
Variables and types
Store numbers, text and true/false values, and change them.
- 03
Taking input
Read numbers and words that the user types.
- 04
Operators and maths
Do maths, compare values, and avoid the classic division traps.
- 05
If / else
Make your program choose what to do.
- 06
Loops
Repeat code without copying it: for and while.
- 07
Nested loops and patterns
A loop inside a loop: grids, tables and star patterns.
- 08
Methods
Name a piece of code, give it inputs, and reuse it.
- 09
Arrays and lists
Store many values under one name and reach any of them by position.
- 10
Strings
Work with text one character at a time.
- 11
2D arrays
Grids and tables: arrays of arrays.
- 12
Maps and sets
Look things up by key, count things, and keep only unique values.
- 13
Recursion
Methods that call themselves on a smaller problem.
- 14
Classes, sorting and nodes
Your own types, sorting by your own rules, and the nodes behind linked lists.
- 15
How fast is my code?
Count the steps your code takes, read big inputs quickly, and get ready for LeetCode.
Final exam and certificate
Unlocks when you finish the course: 40 lessons to go.