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)
9751	AtCoder ABC203: E. White Pawn
9750	AtCoder ABC203: D. Pond
9749	AtCoder ABC203: C. Friends and Travel costs
9748	AtCoder ABC203: B. AtCoder Condominium
9747	AtCoder ABC203: A. Chinchirorin
9746	AtCoder ABC202: F. Integer Convex Hull
9745	AtCoder ABC202: E. Count Descendants
9744	AtCoder ABC202: D. aab aba baa
9743	AtCoder ABC202: C. Made Up
9742	AtCoder ABC202: B. 180°
9741	AtCoder ABC202: A. Three Dice
9740	AtCoder ABC201: F. Insertion Sort
9739	AtCoder ABC201: E. Xor Distances
9738	AtCoder ABC201: D. Game in Momotetsu World
9737	AtCoder ABC201: C. Secret Number
9736	AtCoder ABC201: B. Do you know the second highest mountain?
9735	AtCoder ABC201: A. Tiny Arithmetic Sequence
9734	AtCoder ABC200: F. Minflip Summation
9733	AtCoder ABC200: E. Patisserie ABC 2
9732	AtCoder ABC200: D. Happy Birthday! 2
9731	AtCoder ABC200: C. Ringo's Favorite Numbers 2
9730	AtCoder ABC200: B. 200th ABC-200
9729	AtCoder ABC200: A. Century
9728	AtCoder ABC199: F. Graph Smoothing
9727	AtCoder ABC199: E. Permutation
9726	AtCoder ABC199: D. RGB Coloring 2
9725	AtCoder ABC199: C. IPFL
9724	AtCoder ABC199: B. Intersection
9723	AtCoder ABC199: A. Square Inequality
9722	AtCoder ABC198: F. Cube
9721	AtCoder ABC198: E. Unique Color
9720	AtCoder ABC198: D. Send More Money
9719	AtCoder ABC198: C. Compass Walking
9718	AtCoder ABC198: B. Palindrome with leading zeros
9717	AtCoder ABC198: A. Div
9716	AtCoder ABC197: F. Construct a Palindrome
9715	AtCoder ABC197: E. Traveler
9714	AtCoder ABC197: D. Opposite
9713	AtCoder ABC197: C. ORXOR
9712	AtCoder ABC197: B. Visibility
9711	AtCoder ABC197: A. Rotate
9710	AtCoder ABC196: F. Substring 2
9709	AtCoder ABC196: E. Filters
9708	AtCoder ABC196: D. Hanjo
9707	AtCoder ABC196: C. Doubled
9706	AtCoder ABC196: B. Round Down
9705	AtCoder ABC196: A. Difference Max
9704	AtCoder ABC195: F. Coprime Present
9703	AtCoder ABC195: E. Lucky 7 Battle
9702	AtCoder ABC195: D. Shipping Center

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

9751

AtCoder ABC203: E. White Pawn

9750

AtCoder ABC203: D. Pond

9749

AtCoder ABC203: C. Friends and Travel costs

9748

AtCoder ABC203: B. AtCoder Condominium

9747

AtCoder ABC203: A. Chinchirorin

9746