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)
10901	AtCoder AGC046: A. Takahashikun, The Strider
10900	AtCoder AGC045: F. Division into Multiples
10899	AtCoder AGC045: E. Fragile Balls
10898	AtCoder AGC045: D. Lamps and Buttons
10897	AtCoder AGC045: C. Range Set
10896	AtCoder AGC045: B. 01 Unbalanced
10895	AtCoder AGC045: A. Xor Battle
10894	AtCoder AGC044: F. Name-Preserving Clubs
10893	AtCoder AGC044: E. Random Pawn
10892	AtCoder AGC044: D. Guess the Password
10891	AtCoder AGC044: C. Strange Dance
10890	AtCoder AGC044: B. Joker
10889	AtCoder AGC044: A. Pay to Win
10888	AtCoder AGC043: F. Jewelry Box
10887	AtCoder AGC043: E. Topology
10886	AtCoder AGC043: D. Merge Triplets
10885	AtCoder AGC043: C. Giant Graph
10884	AtCoder AGC043: B. 123 Triangle
10883	AtCoder AGC043: A. Range Flip Find Route
10882	AtCoder AGC041: F. Histogram Rooks
10881	AtCoder AGC041: E. Balancing Network
10880	AtCoder AGC041: D. Problem Scores
10879	AtCoder AGC041: C. Domino Quality
10878	AtCoder AGC041: B. Voting Judges
10877	AtCoder AGC041: A. Table Tennis Training
10876	AtCoder AGC040: F. Two Pieces
10875	AtCoder AGC040: E. Prefix Suffix Addition
10874	AtCoder AGC040: D. Balance Beam
10873	AtCoder AGC040: C. Neither AB nor BA
10872	AtCoder AGC040: B. Two Contests
10871	AtCoder AGC040: A. ><
10870	AtCoder AGC039: F. Min Product Sum
10869	AtCoder AGC039: E. Pairing Points
10868	AtCoder AGC039: D. Incenters
10867	AtCoder AGC039: C. Division by Two with Something
10866	AtCoder AGC039: B. Graph Partition
10865	AtCoder AGC039: A. Connection and Disconnection
10864	AtCoder AGC038: F. Two Permutations
10863	AtCoder AGC038: E. Gachapon
10862	AtCoder AGC038: D. Unique Path
10861	AtCoder AGC038: C. LCMs
10860	AtCoder AGC038: B. Sorting a Segment
10859	AtCoder AGC038: A. 01 Matrix
10858	AtCoder AGC037: F. Counting of Subarrays
10857	AtCoder AGC037: E. Reversing and Concatenating
10856	AtCoder AGC037: D. Sorting a Grid
10855	AtCoder AGC037: C. Numbers on a Circle
10854	AtCoder AGC037: B. RGB Balls
10853	AtCoder AGC037: A. Dividing a String
10852	AtCoder AGC036: F. Square Constraints

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

10901

AtCoder AGC046: A. Takahashikun, The Strider

10900

AtCoder AGC045: F. Division into Multiples

10899

AtCoder AGC045: E. Fragile Balls

10898

AtCoder AGC045: D. Lamps and Buttons

10897

AtCoder AGC045: C. Range Set

10896