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Amazon — DSA Interview Questions

40 problems with animated explanations & C# solutions. (~360 common interview questions)

Step through algorithms visually, then solve with stdin/stdout auto-judge.

Medium Graph Valid Tree

Medium Cheapest Flights Within K Stops

Medium Decode Ways

Medium Longest Common Subsequence

Hard Edit Distance

Medium Hand of Straights

Easy Meeting Rooms

Easy Reverse Bits

Medium Group Anagrams

Medium Two Sum II - Input Array Is Sorted

Medium Permutation in String

Medium Daily Temperatures

Medium Search in Rotated Sorted Array

Medium Copy List with Random Pointer

Easy Invert Binary Tree

Medium Binary Tree Level Order Traversal

Hard Serialize and Deserialize Binary Tree

Medium Kth Largest Element in an Array

Medium Subsets II

Medium Clone Graph

Medium Course Schedule II

Medium Network Delay Time

Medium House Robber II

Medium Longest Increasing Subsequence

Medium Interleaving String

Medium Jump Game

Medium Insert Interval

Medium Spiral Matrix

Easy Single Number

Easy Contains Duplicate

Medium Encode and Decode Strings

Easy Best Time to Buy and Sell Stock

Medium Min Stack

Medium Search a 2D Matrix

Easy Merge Two Sorted Lists

Medium LRU Cache

Medium Kth Smallest Element in a BST

Easy Kth Largest Element in a Stream

Animate All companies

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