Starlight: List of Problems

Over 20,000 problems available. AMC 8/10/12 and AIME problems from 2010-2023; USAJMO/USAMO problems from 2002-2023 available. USACO problems from 2014 to 2023 (all divisions). Codeforces, AtCoder, DMOJ problems are added daily around 04:00 AM UTC, which may cause disruptions.

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AMC 8: [year] AMC 8 Problem #, Ex: 2013 AMC 8 Problem 1
AMC 10: [year] AMC 10A Problem # OR [year] AMC 10B Problem #, Ex: 2015 AMC 10A Problem 16
AMC 12: [year] AMC 12A Problem # OR [year] AMC 12B Problem #, Ex: 2021 AMC 12B Problem 25
AIME: [year] AIME I Problem # OR [year] AIME II Problem #, Ex: 2013 AIME I Problem 8
USAJMO/USAMO: [year] USAJMO/USAMO Problem #, Ex: 2023 USAJMO Problem 1
Codeforces: Codeforces [contest id (e.g. 101)][problem id (e.g. A, B, C)]: [Codeforces problem name], Ex: Codeforces 1336F: Journey
AtCoder: AtCoder [contest id (e.g. ABC314, ARC164, ZONE2021)]: [problem id (A, B, C)]. [Problem name], Ex: AtCoder ZONE2021: E. Sneaking
DMOJ: DMOJ [contest name (if applicable)] [problem number (e.g. P1)] - [Problem name], Ex: DMOJ Yet Another Contest 3 P1 - Shell Swap Scam
USACO: [year] [contest month (e.g. January, US Open)], [division (e.g. Gold)]: [Problem name], Ex: USACO 2023 US Open Contest, Bronze: Rotate and Shift

ID	Problem Name (click to add insights/hints, view summary of insights/hints and similar problems)
17351	DMOJ DWITE '07 R5 #4 - Train ride
17350	DMOJ DWITE '07 R5 #3 - Parity bit
17349	DMOJ DWITE '07 R5 #2 - Number of factors
17348	DMOJ DWITE '07 R5 #1 - I heart you
17347	DMOJ DWITE '07 R4 #5 - It all adds up
17346	DMOJ DWITE '07 R4 #4 - Shortest path around
17345	DMOJ DWITE '07 R4 #3 - Don't follow my links
17344	DMOJ DWITE '07 R4 #2 - And the winner is...
17343	DMOJ DWITE '07 R4 #1 - Curve-shot
17342	DMOJ DWITE '07 R3 #5 - Portals
17341	DMOJ DWITE '07 R3 #4 - The Convex Fence Company
17340	DMOJ DWITE '07 R3 #3 - Playlist
17339	DMOJ DWITE '07 R3 #2 - There's An Essay In My Code
17338	DMOJ DWITE '07 R3 #1 - Yet Another Primes Question
17337	DMOJ DWITE '07 R2 #5 - Bridges In A Graph
17336	DMOJ DWITE '07 R2 #4 - All Is Balanced
17335	DMOJ DWITE '07 R2 #3 - Floor Plan
17334	DMOJ DWITE '07 R2 #2 - Show Me The Money!
17333	DMOJ DWITE '07 R2 #1 - Not Quite Prime
17332	DMOJ DWITE '07 R1 #5 - Velociraptor Maze
17331	DMOJ DWITE '07 R1 #4 - Stacks of Blocks
17330	DMOJ DWITE '07 R1 #3 - Where's my QWERTY?
17329	DMOJ DWITE '07 R1 #2 - Cubes in a Pyramid
17328	DMOJ DWITE '07 R1 #1 - Vanilla Primes
17327	DMOJ DWITE '06 R5 #5 - Prime Palindromes
17326	DMOJ DWITE '06 R5 #4 - Connect-4
17325	DMOJ DWITE '06 R5 #3 - UPC Check Digit
17324	DMOJ DWITE '06 R5 #2 - Floppy Disk
17323	DMOJ DWITE '06 R5 #1 - Points on a Line
17322	DMOJ DWITE '02 R2 #5 - Now I know my ABCs
17321	DMOJ DWITE '02 R2 #4 - Money Prize
17320	DMOJ DWITE '02 R2 #3 - The Game of Life
17319	DMOJ DWITE '02 R2 #2 - The Five M's of Stats 101
17318	DMOJ DWITE '02 R2 #1 - Sales!
17317	DMOJ Diagnostic Test '16 Level 2 P3 - Remove Cancer
17316	DMOJ Diagnostic Test '16 Level 2 P2 - Gibe clays
17315	DMOJ Diagnostic Test '16 Level 2 P1 - Polan cannot into space
17314	DMOJ Diagnostic Test '16 Level 1 P3 - Faxen Words
17313	DMOJ Diagnostic Test '16 Level 1 P2 - FaxPrimes
17312	DMOJ Diagnostic Test '16 Level 1 P1 - StarMath
17311	DMOJ DS '19 Day 2 P3 Inaho C
17310	DMOJ DS '19 Day 1 P1 - Arithmetic Square
17309	DMOJ String Test
17308	DMOJ Dynamic Tree Test (Easy)
17307	DMOJ Dynamic Tree Test
17306	DMOJ Binary Search Tree Test
17305	DMOJ Segment Tree Test
17304	DMOJ Disjoint Set Test
17303	DMOJ Binary Indexed Tree Test
17302	DMOJ Division Queries and Updates

Problem Name (click to add insights/hints, view summary of insights/hints and similar problems)

17351

DMOJ DWITE '07 R5 #4 - Train ride

17350

DMOJ DWITE '07 R5 #3 - Parity bit

17349

DMOJ DWITE '07 R5 #2 - Number of factors

17348

DMOJ DWITE '07 R5 #1 - I heart you

17347

DMOJ DWITE '07 R4 #5 - It all adds up

17346