company prep
Uber
Problems frequently reported at Uber, in course order. Solve the must-dos first.
2 easy25 medium9 hardSimulation ×3Tree BFS (level order) ×3Graph DFS / BFS traversal ×3Topological sort & cycle detection ×3Recursion on a smaller input ×2Binary search (exact & bounds) ×2
08 · Recursion
- #24Swap Nodes in PairsMedium
- #427Construct Quad TreeMedium
09 · Math & Number Theory
- #528Random Pick with WeightMediummust-do
10 · Arrays & Strings
- #238Product of Array Except SelfMediummust-do
11 · Matrices & Simulation
- #54Spiral MatrixMediummust-do
12 · Two Pointers
- #977Squares of a Sorted ArrayEasy
14 · Hashing & Prefix Sums
- #36Valid SudokuMedium
16 · Stacks & Monotonic Stack
- #735Asteroid CollisionMediummust-do
17 · Queues & Deques
- #362Design Hit CounterMedium
20 · String Parsing & Expression Evaluation
- #224Basic CalculatorHardmust-do
- #68Text JustificationHard
21 · Tree Traversals
- #199Binary Tree Right Side ViewMediummust-do
- #297Serialize and Deserialize Binary TreeHardmust-do
22 · Tree Recursion
- #104Maximum Depth of Binary TreeEasymust-do
23 · Binary Search Trees
- #450Delete Node in a BSTMediummust-do
- #230Kth Smallest Element in a BSTMediummust-do
- #729My Calendar IMedium
24 · Heaps & Priority Queues
- #692Top K Frequent WordsMedium
25 · Tries
- #212Word Search IIHardmust-do
26 · Graphs: BFS & DFS
- #200Number of IslandsMediummust-do
- #130Surrounded RegionsMedium
29 · Topological Sort
- #207Course ScheduleMediummust-do
- #210Course Schedule IIMediummust-do
- #269Alien DictionaryHardmust-do
30 · Advanced Graphs: Euler Paths, Bridges & SCCs
- #332Reconstruct ItineraryHardmust-do
- #399Evaluate DivisionMediummust-do
- #815Bus RoutesHard
31 · Backtracking
- #78SubsetsMediummust-do
- #39Combination SumMediummust-do
- #17Letter Combinations of a Phone NumberMedium
- #79Word SearchMediummust-do
35 · Dynamic Programming
- #139Word BreakMediummust-do
37 · Design Data Structures
- #380Insert Delete GetRandom O(1)Mediummust-do
- #981Time Based Key-Value StoreMediummust-do
- #588Design In-Memory File SystemHard
38 · Segment Trees, Fenwick & String Matching
- #214Shortest PalindromeHard