Amazon Interview Questions 2026 - SDE-1 DSA Prep

Overview

Amazon coding rounds heavily favor trees, arrays/strings, graphs, linked lists, heaps, and design-style problems, with strong emphasis on practical problem solving and clean edge-case handling. For your website, the best Amazon page should feel less like a raw list and more like a study roadmap with high-frequency patterns, target problems, and revision checkpoints.

Most-asked topics

Arrays and stringsTrees and BSTGraphsLinked listsHeaps / priority queuesSliding window and prefix sumBinary searchDynamic programmingRecursion and backtrackingDesign / data-structure implementation

How to prepare

Focus first on arrays, strings, trees, graphs, heaps, linked lists, and dynamic programming.
Practice explaining brute force first, then improving it.
Pay special attention to recursion, BFS/DFS, binary search, sliding window, and hash maps.
Review design-style questions such as LRU Cache, time-based key-value store, and browser history.

Interview Strategy

Amazon interviews usually reward candidates who can break a problem into cases, explain trade-offs clearly, and write production-friendly code. Their questions often feel practical rather than overly theoretical, and many candidates report repeated exposure to tree, graph, and design problems.

Amazon-style solving tips

Prefer clean, direct solutions over over-engineered code.

If the problem has multiple cases, write them explicitly.

Watch for recursion + memoization opportunities.

In graph/tree problems, clarify whether the graph is directed, weighted, or rooted before coding.

For array problems, always test duplicates, empty inputs, and boundary values.

Pattern Map

Recurring patterns you'll see repeatedly in Amazon rounds. Master these first.

1

Tree traversal and subtree logic

2

BFS / DFS on grids and graphs

3

Heap-based selection and scheduling

4

Hash map counting and frequency tracking

5

Sliding window for subarray/string problems

6

Binary search on answer

7

Linked list pointer manipulation

8

Dynamic programming for counting and optimization

9

Interval and scheduling logic

10

Basic design with maps, stacks, queues, and linked lists

Interview style	Practical, pattern-based, clean implementation
Top topics	Trees, graphs, arrays, heaps, linked list, DP
Best first practice	BFS, DFS, binary search, sliding window, heap, recursion
Common traps	Edge cases, recursion mistakes, missed null handling
High-value problem types	Design, tree traversal, graph traversal, scheduling
Prep goal	Solve patterns, not memorize only titles

Must-Solve Problems

Curated Amazon-style problem set — grouped by topic bucket. All links are free on LeetCode.

Arrays and Strings10

Binary Search6

Linked List6

Stack and Queue6

Trees10

BST6

Heaps6

Graphs8

Dynamic Programming8

Greedy and Scheduling6

Design-style Amazon picks6

Year-Wise Question Trends

The most trustworthy way to present recency for Amazon is by trend buckets — not fake exact yearly dates.

2026

2026 focus: recent company-wise Amazon lists and current trend questions.

2025

2025 focus: stable repeat patterns from Amazon-tagged interview collections.

Evergreen

Older evergreen questions: problems that remain high-value because the pattern repeats often.

Practice Set & Revision Checklist

Use this checklist for last-mile revision — tick items as you clear them.

Trees: preorder, inorder, level order, LCA, subtreeGraphs: BFS, DFS, shortest path, cycle detectionArrays: two sum, sliding window, prefix sum, binary searchLinked list: reverse, cycle, merge, copy random listHeap: top K, kth element, median, merging listsDP: house robber, climbing stairs, unique paths, coin changeDesign: LRU cache, browser history, snapshot array

Amazon Interview Questions & Placement Prep (2026)