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)
11001	AtCoder AGC062: E. Overlap Binary Tree
11000	AtCoder AGC062: D. Walk Around Neighborhood
10999	AtCoder AGC062: C. Mex of Subset Sum
10998	AtCoder AGC062: B. Split and Insert
10997	AtCoder AGC062: A. Right Side Character
10996	AtCoder AGC061: F. Perfect Strings
10995	AtCoder AGC061: E. Increment or XOR
10994	AtCoder AGC061: D. Almost Multiplication Table
10993	AtCoder AGC061: C. First Come First Serve
10992	AtCoder AGC061: B. Summation By Construction
10991	AtCoder AGC061: A. Long Shuffle
10990	AtCoder AGC060: F. Spanning Trees of Interval Graph
10989	AtCoder AGC060: E. Number of Cycles
10988	AtCoder AGC060: D. Same Descent Set
10987	AtCoder AGC060: C. Large Heap
10986	AtCoder AGC060: B. Unique XOR Path
10985	AtCoder AGC060: A. No Majority
10984	AtCoder AGC059: F. LIDS
10983	AtCoder AGC059: E. Grid 3-coloring
10982	AtCoder AGC059: D. Distinct Elements on Subsegments
10981	AtCoder AGC059: C. Guessing Permutation for as Long as Possible
10980	AtCoder AGC059: B. Arrange Your Balls
10979	AtCoder AGC059: A. My Last ABC Problem
10978	AtCoder AGC058: F. Authentic Tree DP
10977	AtCoder AGC058: E. Nearer Permutation
10976	AtCoder AGC058: D. Yet Another ABC String
10975	AtCoder AGC058: C. Planar Tree
10974	AtCoder AGC058: B. Adjacent Chmax
10973	AtCoder AGC058: A. Make it Zigzag
10972	AtCoder AGC057: F. Reflection
10971	AtCoder AGC057: E. RowCol/ColRow Sort
10970	AtCoder AGC057: D. Sum Avoidance
10969	AtCoder AGC057: C. Increment or Xor
10968	AtCoder AGC057: B. 2A + x
10967	AtCoder AGC057: A. Antichain of Integer Strings
10966	AtCoder AGC056: F. Degree Sequence in DFS Order
10965	AtCoder AGC056: E. Cheese
10964	AtCoder AGC056: D. Subset Sum Game
10963	AtCoder AGC056: C. 01 Balanced
10962	AtCoder AGC056: B. Range Argmax
10961	AtCoder AGC056: A. Three Cells per Row and Column
10960	AtCoder AGC055: F. Creative Splitting
10959	AtCoder AGC055: E. Set Merging
10958	AtCoder AGC055: D. ABC Ultimatum
10957	AtCoder AGC055: C. Weird LIS
10956	AtCoder AGC055: B. ABC Supremacy
10955	AtCoder AGC055: A. ABC Identity
10954	AtCoder AGC054: F. Decrement
10953	AtCoder AGC054: E. ZigZag Break
10952	AtCoder AGC054: D. (ox)

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

11001

AtCoder AGC062: E. Overlap Binary Tree

11000

AtCoder AGC062: D. Walk Around Neighborhood

10999

AtCoder AGC062: C. Mex of Subset Sum

10998

AtCoder AGC062: B. Split and Insert

10997

AtCoder AGC062: A. Right Side Character

10996