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)
11401	AtCoder ABC081: D. Non-decreasing
11400	AtCoder ABC081: C. Not so Diverse
11399	AtCoder ARC085: F. NRE
11398	AtCoder ARC085: E. MUL
11397	AtCoder ABC078: D. ABS
11396	AtCoder ABC078: C. HSI
11395	AtCoder ARC084: F. XorShift
11394	AtCoder ARC084: E. Finite Encyclopedia of Integer Sequences
11393	AtCoder ABC077: D. Small Multiple
11392	AtCoder ABC077: C. Snuke Festival
11391	AtCoder ARC083: F. Collecting Balls
11390	AtCoder ARC083: E. Bichrome Tree
11389	AtCoder ABC074: D. Restoring Road Network
11388	AtCoder ABC074: C. Sugar Water
11387	AtCoder ARC082: F. Sandglass
11386	AtCoder ARC082: E. ConvexScore
11385	AtCoder ABC072: D. Derangement
11384	AtCoder ABC072: C. Together
11383	AtCoder ARC081: F. Flip and Rectangles
11382	AtCoder ARC081: E. Don't Be a Subsequence
11381	AtCoder ABC071: D. Coloring Dominoes
11380	AtCoder ABC071: C. Make a Rectangle
11379	AtCoder ARC080: F. Prime Flip
11378	AtCoder ARC080: E. Young Maids
11377	AtCoder ABC069: D. Grid Coloring
11376	AtCoder ABC069: C. 4-adjacent
11375	AtCoder ARC079: F. Namori Grundy
11374	AtCoder ARC079: E. Decrease (Judge ver.)
11373	AtCoder ABC068: D. Decrease (Contestant ver.)
11372	AtCoder ABC068: C. Cat Snuke and a Voyage
11371	AtCoder ARC078: F. Mole and Abandoned Mine
11370	AtCoder ARC078: E. Awkward Response
11369	AtCoder ABC067: D. Fennec VS. Snuke
11368	AtCoder ABC067: C. Splitting Pile
11367	AtCoder ARC077: F. SS
11366	AtCoder ARC077: E. guruguru
11365	AtCoder ABC066: D. 11
11364	AtCoder ABC066: C. pushpush
11363	AtCoder ARC076: F. Exhausted?
11362	AtCoder ARC076: E. Connected?
11361	AtCoder ABC065: D. Built?
11360	AtCoder ABC065: C. Reconciled?
11359	AtCoder ARC075: F. Mirrored
11358	AtCoder ARC075: E. Meaningful Mean
11357	AtCoder ABC063: D. Widespread
11356	AtCoder ABC063: C. Bugged
11355	AtCoder ARC074: F. Lotus Leaves
11354	AtCoder ARC074: E. RGB Sequence
11353	AtCoder ABC062: D. 3N Numbers
11352	AtCoder ABC062: C. Chocolate Bar

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

11401

AtCoder ABC081: D. Non-decreasing

11400

AtCoder ABC081: C. Not so Diverse

11399

AtCoder ARC085: F. NRE

11398

AtCoder ARC085: E. MUL

11397

AtCoder ABC078: D. ABS

11396