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)
7751	Codeforces 1674F: Desktop Rearrangement
7750	Codeforces 1674E: Breaking the Wall
7749	Codeforces 1674D: A-B-C Sort
7748	Codeforces 1674C: Infinite Replacement
7747	Codeforces 1674B: Dictionary
7746	Codeforces 1674A: Number Transformation
7745	Codeforces 1673F: Anti-Theft Road Planning
7744	Codeforces 1673E: Power or XOR?
7743	Codeforces 1673D: Lost Arithmetic Progression
7742	Codeforces 1673C: Palindrome Basis
7741	Codeforces 1673B: A Perfectly Balanced String?
7740	Codeforces 1673A: Subtle Substring Subtraction
7739	Codeforces 1672I: PermutationForces
7738	Codeforces 1672H: Zigu Zagu
7737	Codeforces 1672G: Cross Xor
7736	Codeforces 1672F2: Checker for Array Shuffling
7735	Codeforces 1672F1: Array Shuffling
7734	Codeforces 1672E: notepad.exe
7733	Codeforces 1672D: Cyclic Rotation
7732	Codeforces 1672C: Unequal Array
7731	Codeforces 1672B: I love AAAB
7730	Codeforces 1672A: Log Chopping
7729	Codeforces 1671F: Permutation Counting
7728	Codeforces 1671E: Preorder
7727	Codeforces 1671D: Insert a Progression
7726	Codeforces 1671C: Dolce Vita
7725	Codeforces 1671B: Consecutive Points Segment
7724	Codeforces 1671A: String Building
7723	Codeforces 1670F: Jee, You See?
7722	Codeforces 1670E: Hemose on the Tree
7721	Codeforces 1670D: Very Suspicious
7720	Codeforces 1670C: Where is the Pizza?
7719	Codeforces 1670B: Dorms War
7718	Codeforces 1670A: Prof. Slim
7717	Codeforces 1669H: Maximal AND
7716	Codeforces 1669G: Fall Down
7715	Codeforces 1669F: Eating Candies
7714	Codeforces 1669E: 2-Letter Strings
7713	Codeforces 1669D: Colorful Stamp
7712	Codeforces 1669C: Odd/Even Increments
7711	Codeforces 1669B: Triple
7710	Codeforces 1669A: Division?
7709	Codeforces 1668B: Social Distance
7708	Codeforces 1668A: Direction Change
7707	Codeforces 1667F: Yin Yang
7706	Codeforces 1667E: Centroid Probabilities
7705	Codeforces 1667D: Edge Elimination
7704	Codeforces 1667C: Half Queen Cover
7703	Codeforces 1667B: Optimal Partition
7702	Codeforces 1667A: Make it Increasing

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

7751

Codeforces 1674F: Desktop Rearrangement

7750

Codeforces 1674E: Breaking the Wall

7749

Codeforces 1674D: A-B-C Sort

7748

Codeforces 1674C: Infinite Replacement

7747

Codeforces 1674B: Dictionary

7746