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)
9901	AtCoder ABC224: E. Integers on Grid
9900	AtCoder ABC224: D. 8 Puzzle on Graph
9899	AtCoder ABC224: C. Triangle?
9898	AtCoder ABC224: B. Mongeness
9897	AtCoder ABC224: A. Tires
9896	AtCoder ABC223: H. Xor Query
9895	AtCoder ABC223: G. Vertex Deletion
9894	AtCoder ABC223: F. Parenthesis Checking
9893	AtCoder ABC223: E. Placing Rectangles
9892	AtCoder ABC223: D. Restricted Permutation
9891	AtCoder ABC223: C. Doukasen
9890	AtCoder ABC223: B. String Shifting
9889	AtCoder ABC223: A. Exact Price
9888	AtCoder ABC222: H. Beautiful Binary Tree
9887	AtCoder ABC222: G. 222
9886	AtCoder ABC222: F. Expensive Expense
9885	AtCoder ABC222: E. Red and Blue Tree
9884	AtCoder ABC222: D. Between Two Arrays
9883	AtCoder ABC222: C. Swiss-System Tournament
9882	AtCoder ABC222: B. Failing Grade
9881	AtCoder ABC222: A. Four Digits
9880	AtCoder ABC221: H. Count Multiset
9879	AtCoder ABC221: G. Jumping sequence
9878	AtCoder ABC221: F. Diameter set
9877	AtCoder ABC221: E. LEQ
9876	AtCoder ABC221: D. Online games
9875	AtCoder ABC221: C. Select Mul
9874	AtCoder ABC221: B. typo
9873	AtCoder ABC221: A. Seismic magnitude scales
9872	AtCoder ABC220: H. Security Camera
9871	AtCoder ABC220: G. Isosceles Trapezium
9870	AtCoder ABC220: F. Distance Sums 2
9869	AtCoder ABC220: E. Distance on Large Perfect Binary Tree
9868	AtCoder ABC220: D. FG operation
9867	AtCoder ABC220: C. Long Sequence
9866	AtCoder ABC220: B. Base K
9865	AtCoder ABC220: A. Find Multiple
9864	AtCoder ABC219: H. Candles
9863	AtCoder ABC219: G. Propagation
9862	AtCoder ABC219: F. Cleaning Robot
9861	AtCoder ABC219: E. Moat
9860	AtCoder ABC219: D. Strange Lunchbox
9859	AtCoder ABC219: C. Neo-lexicographic Ordering
9858	AtCoder ABC219: B. Maritozzo
9857	AtCoder ABC219: A. AtCoder Quiz 2
9856	AtCoder ABC218: H. Red and Blue Lamps
9855	AtCoder ABC218: G. Game on Tree 2
9854	AtCoder ABC218: F. Blocked Roads
9853	AtCoder ABC218: E. Destruction
9852	AtCoder ABC218: D. Rectangles

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

9901

AtCoder ABC224: E. Integers on Grid

9900

AtCoder ABC224: D. 8 Puzzle on Graph

9899

AtCoder ABC224: C. Triangle?

9898

AtCoder ABC224: B. Mongeness

9897

AtCoder ABC224: A. Tires

9896