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)
6651	Codeforces 1472A: Cards for Friends
6650	Codeforces 1471B: Strange List
6649	Codeforces 1471A: Strange Partition
6648	Codeforces 1470F: Strange Covering
6647	Codeforces 1470E: Strange Permutation
6646	Codeforces 1470D: Strange Housing
6645	Codeforces 1470C: Strange Shuffle
6644	Codeforces 1470B: Strange Definition
6643	Codeforces 1470A: Strange Birthday Party
6642	Codeforces 1469F: Power Sockets
6641	Codeforces 1469E: A Bit Similar
6640	Codeforces 1469D: Ceil Divisions
6639	Codeforces 1469C: Building a Fence
6638	Codeforces 1469B: Red and Blue
6637	Codeforces 1469A: Regular Bracket Sequence
6636	Codeforces 1468N: Waste Sorting
6635	Codeforces 1468M: Similar Sets
6634	Codeforces 1468L: Prime Divisors Selection
6633	Codeforces 1468K: The Robot
6632	Codeforces 1468J: Road Reform
6631	Codeforces 1468I: Plane Tiling
6630	Codeforces 1468H: K and Medians
6629	Codeforces 1468G: Hobbits
6628	Codeforces 1468F: Full Turn
6627	Codeforces 1468E: Four Segments
6626	Codeforces 1468D: Firecrackers
6625	Codeforces 1468C: Berpizza
6624	Codeforces 1468B: Bakery
6623	Codeforces 1468A: LaIS
6622	Codeforces 1467E: Distinctive Roots in a Tree
6621	Codeforces 1467D: Sum of Paths
6620	Codeforces 1467C: Three Bags
6619	Codeforces 1467B: Hills And Valleys
6618	Codeforces 1467A: Wizard of Orz
6617	Codeforces 1466I: The Riddle of the Sphinx
6616	Codeforces 1466H: Finding satisfactory solutions
6615	Codeforces 1466G: Song of the Sirens
6614	Codeforces 1466F: Euclid's nightmare
6613	Codeforces 1466E: Apollo versus Pan
6612	Codeforces 1466D: 13th Labour of Heracles
6611	Codeforces 1466C: Canine poetry
6610	Codeforces 1466B: Last minute enhancements
6609	Codeforces 1466A: Bovine Dilemma
6608	Codeforces 1464F: My Beautiful Madness
6607	Codeforces 1463F: Max Correct Set
6606	Codeforces 1463E: Plan of Lectures
6605	Codeforces 1463D: Pairs
6604	Codeforces 1463C: Busy Robot
6603	Codeforces 1463B: Find The Array
6602	Codeforces 1463A: Dungeon

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

6651

Codeforces 1472A: Cards for Friends

6650

Codeforces 1471B: Strange List

6649

Codeforces 1471A: Strange Partition

6648

Codeforces 1470F: Strange Covering

6647

Codeforces 1470E: Strange Permutation

6646