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)
1601	Codeforces 362D: Fools and Foolproof Roads
1600	Codeforces 362C: Insertion Sort
1599	Codeforces 362B: Petya and Staircases
1598	Codeforces 362A: Two Semiknights Meet
1597	Codeforces 361B: Levko and Permutation
1596	Codeforces 361A: Levko and Table
1595	Codeforces 360E: Levko and Game
1594	Codeforces 360D: Levko and Sets
1593	Codeforces 360C: Levko and Strings
1592	Codeforces 360B: Levko and Array
1591	Codeforces 360A: Levko and Array Recovery
1590	Codeforces 359E: Neatness
1589	Codeforces 359D: Pair of Numbers
1588	Codeforces 359C: Prime Number
1587	Codeforces 359B: Permutation
1586	Codeforces 359A: Table
1585	Codeforces 358E: Dima and Kicks
1584	Codeforces 358D: Dima and Hares
1583	Codeforces 358C: Dima and Containers
1582	Codeforces 358B: Dima and Text Messages
1581	Codeforces 358A: Dima and Continuous Line
1580	Codeforces 357B: Flag Day
1579	Codeforces 357A: Group of Students
1578	Codeforces 356E: Xenia and String Problem
1577	Codeforces 356D: Bags and Coins
1576	Codeforces 356C: Compartments
1575	Codeforces 356B: Xenia and Hamming
1574	Codeforces 356A: Knight Tournament
1573	Codeforces 355B: Vasya and Public Transport
1572	Codeforces 355A: Vasya and Digital Root
1571	Codeforces 354E: Lucky Number Representation
1570	Codeforces 354D: Transferring Pyramid
1569	Codeforces 354C: Vasya and Beautiful Arrays
1568	Codeforces 354B: Game with Strings
1567	Codeforces 354A: Vasya and Robot
1566	Codeforces 353E: Antichain
1565	Codeforces 353D: Queue
1564	Codeforces 353C: Find Maximum
1563	Codeforces 353B: Two Heaps
1562	Codeforces 353A: Domino
1561	Codeforces 352B: Jeff and Periods
1560	Codeforces 352A: Jeff and Digits
1559	Codeforces 351E: Jeff and Permutation
1558	Codeforces 351D: Jeff and Removing Periods
1557	Codeforces 351C: Jeff and Brackets
1556	Codeforces 351B: Jeff and Furik
1555	Codeforces 351A: Jeff and Rounding
1554	Codeforces 350E: Wrong Floyd
1553	Codeforces 350D: Looking for Owls
1552	Codeforces 350C: Bombs

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

1601

Codeforces 362D: Fools and Foolproof Roads

1600

Codeforces 362C: Insertion Sort

1599

Codeforces 362B: Petya and Staircases

1598

Codeforces 362A: Two Semiknights Meet

1597

Codeforces 361B: Levko and Permutation

1596