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)
5251	Codeforces 1195E: OpenStreetMap
5250	Codeforces 1195D2: Submarine in the Rybinsk Sea (hard edition)
5249	Codeforces 1195D1: Submarine in the Rybinsk Sea (easy edition)
5248	Codeforces 1195C: Basketball Exercise
5247	Codeforces 1195B: Sport Mafia
5246	Codeforces 1195A: Drinks Choosing
5245	Codeforces 1194G: Another Meme Problem
5244	Codeforces 1194F: Crossword Expert
5243	Codeforces 1194E: Count The Rectangles
5242	Codeforces 1194D: 1-2-K Game
5241	Codeforces 1194C: From S To T
5240	Codeforces 1194B: Yet Another Crosses Problem
5239	Codeforces 1194A: Remove a Progression
5238	Codeforces 1193C: Scissors and Tape
5237	Codeforces 1193B: Magic Tree
5236	Codeforces 1193A: Amusement Park
5235	Codeforces 1192C: Cubeword
5234	Codeforces 1192B: Dynamic Diameter
5233	Codeforces 1192A: Building Skyscrapers
5232	Codeforces 1191B: Tokitsukaze and Mahjong
5231	Codeforces 1191A: Tokitsukaze and Enhancement
5230	Codeforces 1190F: Tokitsukaze and Powers
5229	Codeforces 1190E: Tokitsukaze and Explosion
5228	Codeforces 1190D: Tokitsukaze and Strange Rectangle
5227	Codeforces 1190C: Tokitsukaze and Duel
5226	Codeforces 1190B: Tokitsukaze, CSL and Stone Game
5225	Codeforces 1190A: Tokitsukaze and Discard Items
5224	Codeforces 1189C: Candies!
5223	Codeforces 1189B: Number Circle
5222	Codeforces 1189A: Keanu Reeves
5221	Codeforces 1188E: Problem from Red Panda
5220	Codeforces 1188D: Make Equal
5219	Codeforces 1188C: Array Beauty
5218	Codeforces 1188B: Count Pairs
5217	Codeforces 1188A2: Add on a Tree: Revolution
5216	Codeforces 1188A1: Add on a Tree
5215	Codeforces 1187G: Gang Up
5214	Codeforces 1187F: Expected Square Beauty
5213	Codeforces 1187E: Tree Painting
5212	Codeforces 1187D: Subarray Sorting
5211	Codeforces 1187C: Vasya And Array
5210	Codeforces 1187B: Letters Shop
5209	Codeforces 1187A: Stickers and Toys
5208	Codeforces 1186F: Vus the Cossack and a Graph
5207	Codeforces 1186E: Vus the Cossack and a Field
5206	Codeforces 1186D: Vus the Cossack and Numbers
5205	Codeforces 1186C: Vus the Cossack and Strings
5204	Codeforces 1186A: Vus the Cossack and a Contest
5203	Codeforces 1185G2: Playlist for Polycarp (hard version)
5202	Codeforces 1185G1: Playlist for Polycarp (easy version)

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

5251

Codeforces 1195E: OpenStreetMap

5250

Codeforces 1195D2: Submarine in the Rybinsk Sea (hard edition)

5249

Codeforces 1195D1: Submarine in the Rybinsk Sea (easy edition)

5248

Codeforces 1195C: Basketball Exercise

5247

Codeforces 1195B: Sport Mafia

5246