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)
23901	Codeforces 1866I: Imagination Castle
23900	Codeforces 1866H: Happy Sets
23899	Codeforces 1866G: Grouped Carriages
23898	Codeforces 1866F: Freak Joker Process
23897	Codeforces 1866E: Elevators of Tamem
23896	Codeforces 1866D: Digital Wallet
23895	Codeforces 1866C: Completely Searching for Inversions
23894	Codeforces 1866B: Battling with Numbers
23893	Codeforces 1866A: Ambitious Kid
23892	AtCoder ABC318: Ex. Count Strong Test Cases
23891	AtCoder ABC318: G. Typical Path Problem
23890	AtCoder ABC318: F. Octopus
23889	AtCoder ABC318: E. Sandwiches
23888	AtCoder ABC318: D. General Weighted Max Matching
23887	AtCoder ABC318: C. Blue Spring
23886	AtCoder ABC318: B. Overlapping sheets
23885	AtCoder ABC318: A. Full Moon
23884	DMOJ IOI '23 P3 - Soccer Stadium
23883	DMOJ IOI '23 P2 - Longest Trip
23882	DMOJ IOI '23 P1 - Closing Time
23881	Codeforces 1861F: Four Suits
23880	Codeforces 1861E: Non-Intersecting Subpermutations
23879	Codeforces 1861D: Sorting By Multiplication
23878	Codeforces 1861C: Queries for the Array
23877	Codeforces 1861B: Two Binary Strings
23876	Codeforces 1861A: Prime Deletion
23875	Codeforces 1863I: Redundant Routes
23874	Codeforces 1863H: Goldberg Machine 3
23873	Codeforces 1863G: Swaps
23872	Codeforces 1863F: Divide, XOR, and Conquer
23871	Codeforces 1863E: Speedrun
23870	Codeforces 1863D: Two-Colored Dominoes
23869	Codeforces 1863C: MEX Repetition
23868	Codeforces 1863B: Split Sort
23867	Codeforces 1863A: Channel
23866	AtCoder TOYOTA2023SUMMER-FINAL-OPEN: A. Transit Warehouse
23865	AtCoder MAXIMUM-CUP-2023: H. 変数の最大化
23864	AtCoder MAXIMUM-CUP-2023: G. イノシシ対策
23863	AtCoder MAXIMUM-CUP-2023: F. 01文字列の構築
23862	AtCoder MAXIMUM-CUP-2023: E. 小大小大……
23861	AtCoder MAXIMUM-CUP-2023: D. 編集ゲーム
23860	AtCoder MAXIMUM-CUP-2023: C. 黒板
23859	AtCoder MAXIMUM-CUP-2023: B. 等差数列と数え上げ
23858	AtCoder MAXIMUM-CUP-2023: A. 倍数ペア
23857	AtCoder ABC317: Ex. Walk
23856	AtCoder ABC317: G. Rearranging
23855	AtCoder ABC317: F. Nim
23854	AtCoder ABC317: E. Avoid Eye Contact
23853	AtCoder ABC317: D. President
23852	AtCoder ABC317: C. Remembering the Days

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

23901

Codeforces 1866I: Imagination Castle

23900

Codeforces 1866H: Happy Sets

23899

Codeforces 1866G: Grouped Carriages

23898

Codeforces 1866F: Freak Joker Process

23897

Codeforces 1866E: Elevators of Tamem

23896