Kuest AI

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Master data structures and algorithms with AI

Prep for coding interviews and your DSA course. Kuest asks how you'd approach a problem, then helps you reason about time, space and edge cases.

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4.87on iOS13,917,000+students already study with Kuest

topics
10
Course
Data structures (CS2) and algorithms
Typical prerequisite
Intro to programming (CS1)
Leads to
Technical interviews, upper-level CS

See how Kuest teaches it

It asks before it tells, so you do the thinking and it sticks.

You: Given an array nums and a target, return the indices of two numbers that add up to target. My nested loop works but it's O(n²).
Kuest: When you're at nums[i], what exact value are you hoping to find somewhere else in the array?
You: target − nums[i].
Kuest: Right. The nested loop searches for that value every time. Which data structure lets you check whether you've already seen a value in O(1)?
You: A hash map. I store each number with its index, and before storing I check if target − nums[i] is already in it.
Kuest: That's the one-pass solution: O(n) time and O(n) space. What should happen if the array is [3, 3] and target is 6?
You: Checking before inserting means the second 3 finds the first, so it returns [0, 1].

When you're searching for a complement repeatedly, a hash map turns an O(n²) scan into an O(n) pass.

Students who lock in with Kuest

students
13,917,000+
App Store rating
4.87
countries
100+

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The method

How to study Data structures & algorithms with Kuest

Getting good at DSA is about recognizing patterns, not memorizing solutions. Explain your approach out loud before you code, state the complexity, and test edge cases by hand. Revisit problems you struggled with a few days later instead of grinding new ones only.

  1. Talk through a problemTutor chat

    Paste the problem and your attempt. Kuest asks about your approach, complexity and edge cases instead of handing over a solution.

  2. Watch the structure changeTeaching board

    Kuest draws arrays, pointers, trees and graphs on the teaching board so you can trace each step of an algorithm.

  3. Practice explaining out loudVoice tutor

    Use the voice tutor to explain your approach like you would in an interview and get follow-up questions.

  4. Review patterns and complexitiesFlashcards

    Spaced flashcards cover patterns like two pointers and sliding window and the Big-O of common operations.

  5. Find weak patternsGap finder

    Kuest notices which problem types trip you up, like graphs or DP, and steers your practice toward them.

  6. Run a mock interviewMock exams

    Take a timed mock exam or an oral exam that feels like a technical screen, then review what to fix.

What you'll cover

Tap a topic to learn it now.

  1. 01Big-O analysisEstimate time and space complexity of loops, nested loops and recursion.
  2. 02Arrays and stringsSolve problems with two pointers, prefix sums and sliding windows.
  3. 03Hash maps and setsTrade memory for O(1) lookups to count, deduplicate and find pairs.
  4. 04Linked listsReverse, merge and detect cycles with pointer manipulation.
  5. 05Stacks and queuesUse LIFO and FIFO structures for parentheses matching, monotonic stacks and BFS.
  6. 06Recursion and backtrackingWrite base cases, trust the recursive call and generate subsets and permutations.
  7. 07Sorting and searchingExplain merge sort and quicksort and apply binary search beyond sorted arrays.
  8. 08Trees and binary search treesTraverse trees in order, pre-order, post-order and level by level.
  9. 09Heaps and graphsUse priority queues and run BFS, DFS and Dijkstra on graphs.
  10. 10Dynamic programmingDefine states and transitions, then build memoized and bottom-up solutions.

Try asking

Tap a question and Kuest starts teaching it, step by step.

Helps you prepare for

  • AP Computer Science A
  • Data structures (CS2) courses
  • Algorithms courses
  • Technical coding interviews

A month of Kuest costs less than one hour with a tutor

Same patience, any hour, every subject. Or stay on the free plan for good.

Private tutor

$40–80for one hour

  • Booked days in advance
  • One subject per session
  • Stops when the hour ends

Kuest Plus

$10a month, billed yearly

  • Every subject and exam on this site
  • Any hour, as long as you need
  • Quizzes, flashcards, podcasts and mock exams

Study on any device

Phone, tablet or laptop. Your chats, plans and flashcards come with you.

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