Practice sheets
One topic at a time, solved three ways.
Work through a topic end to end. Every problem links straight to LeetCode, opens its solution in C++, Java and Python and, where we have drawn one, plays the animated walkthrough.
Free. Log in with a free account to read the solutions and tick problems off.
Practice sheet
Array
1 of 29 done
- Remove Duplicates from Sorted Array
- Search Insert PositionC++JavaPython
// Binary search for insert position.
public int searchInsert(int[] nums, int target)
O(log n) time, O(1) space.
- Merge Sorted Array
- Plus One
- Best Time to Buy and Sell Stock
Practice sheets
Showing 2 sheets
Array sheet
The pattern every interview starts from, two pointers, prefix sums, in-place rewrites and the classic scans.
String sheet
Counting, scanning and rebuilding text: frequency tables, two pointers, parsing, and KMP for the hard ones.
Make your own sheet
Any LeetCode problems, your sections, your order. Share the link and see who uses it.
Your own sheet
Make a sheet, share it, see who uses it.
Put together the list you wish you had when you started: any LeetCode problems, in your order, under your headings. Share the link and watch the learners come in.
Any LeetCode problem
Search by name or number, or paste a list of links. Problems we teach keep their animation and solutions.
Sections your way
Group by day, by topic or by company, and drag problems into the order you want.
Share it anywhere
Every sheet gets its own link and a preview card for LinkedIn, X and WhatsApp.
See who uses it
Your learner count, where they came from, and how many ticked each problem.
Free with any account. Up to 10 sheets of 300 problems each.
How a row works
Everything for one problem, on one line.
No hunting across tabs for the question, a clean solution and an explanation. Each row carries all three.
Solve it on LeetCode
Every row links straight to the problem, so you can write and submit your own code first.
Read it three ways
The solution in C++, Java and Python, with the approach and its complexity in one line.
Watch it move
Where we have drawn one, the animated walkthrough plays right inside the sheet.
Tick it off
Mark a problem done and the sheet keeps count, so you always know what is next.
Pick the first problem and tick it off.
29 problems, three languages, and an animation for every one of them. Start at the top and work down.