Rounds

Live contest set

Current round problems, grouped by difficulty.

IDTitleDifficultySolved
20J
Three at the Top
 Hard
7 / 12
20K
Tree on a Polygon
 Hard
24 / 30
20L
Costly Substrings
 Hard
18 / 41
20M
Hidden Permutation
 Medium
33 / 48
20N
No Self-Purchase
 Medium
56 / 70
20O
Timeless Overtakes
 Medium
61 / 74
20P
Pair Deletion
 Easy
124 / 127
19B
Lattice Paths
 Easy
98 / 101

Classics

Fundamentals

A short curriculum of core techniques.

IDTitleTopicsSolved
CLS1
Hello, World!
Implementation
51 / 52
CLS2
Recursion (Fibonacci)
Math
44 / 48
CLS3
Dynamic Programming (Fibonacci)
DP
23 / 25
CLS4
0/1 Knapsack
DP
19 / 22
CLS5
Unbounded Knapsack
DP
14 / 14
CLS6
Edit Distance
DPStrings
12 / 12
CLS7
Binary Search on Answer
Binary Search
31 / 36
CLS8
Euclidean Algorithm
MathNumber Theory
80 / 92

FAANG

Interview track

Company-tagged questions from recent screens.

IDTitleDifficultyTopicsCompany
FNG1
Irrigation Walk Steps
 Medium
ImplementationGreedy
 Google
FNG2
Repeated Digit Count
 Easy
Math
 Meta
FNG3
Warehouse Merge Windows
 Medium
Two PointersGreedy
 Amazon
FNG4
Catalog Cycle Detect
 Medium
DFSGraphs
 Microsoft
FNG5
Photo Stream Gaps
 Easy
Two Pointers
 Apple
FNG6
Distributed Lock Queue Pro
 Hard
Data Structures
 Microsoft
FNG7
Ads Bid Ladder Pro
 Hard
GreedyMath
 Google
FNG8
Friend Circle Cut
 Medium
DFSGraphs
 Meta

Quant

Probability desk

Expectation, DP, and trading-interview classics.

IDTitleDifficultyTopicsDesk
QUANT1
Monty Switch
 Easy
Probability
 JS
QUANT2
First Head
 Easy
Expectation
 H
QUANT3
Biased Coin Run
 Medium
ProbabilityExpectation
 Σ
QUANT4
Roulette Survival Pro
 Hard
DPProbability
 JS
QUANT5
Order Book Drift
 Medium
Expectation
 H
QUANT6
Kelly Fraction
 Hard
MathProbability
 Σ
QUANT7
Random Walk Barrier
 Medium
DPMath
 JS
QUANT8
Coupon Collector+
 Easy
Expectation
 H