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)
1551	Codeforces 350B: Resort
1550	Codeforces 350A: TL
1549	Codeforces 349B: Color the Fence
1548	Codeforces 349A: Cinema Line
1547	Codeforces 348E: Pilgrims
1546	Codeforces 348D: Turtles
1545	Codeforces 348C: Subset Sums
1544	Codeforces 348B: Apple Tree
1543	Codeforces 348A: Mafia
1542	Codeforces 347B: Fixed Points
1541	Codeforces 347A: Difference Row
1540	Codeforces 346E: Doodle Jump
1539	Codeforces 346D: Robot Control
1538	Codeforces 346C: Number Transformation II
1537	Codeforces 346B: Lucky Common Subsequence
1536	Codeforces 346A: Alice and Bob
1535	Codeforces 345G: Suffix Subgroup
1534	Codeforces 345F: Superstitions Inspection
1533	Codeforces 345E: Black Cat Rush
1532	Codeforces 345D: Chain Letter
1531	Codeforces 345C: Counting Fridays
1530	Codeforces 345B: Triskaidekaphobia
1529	Codeforces 345A: Expecting Trouble
1528	Codeforces 344B: Simple Molecules
1527	Codeforces 344A: Magnets
1526	Codeforces 343E: Pumping Stations
1525	Codeforces 343D: Water Tree
1524	Codeforces 343C: Read Time
1523	Codeforces 343B: Alternating Current
1522	Codeforces 343A: Rational Resistance
1521	Codeforces 342E: Xenia and Tree
1520	Codeforces 342D: Xenia and Dominoes
1519	Codeforces 342C: Cupboard and Balloons
1518	Codeforces 342B: Xenia and Spies
1517	Codeforces 342A: Xenia and Divisors
1516	Codeforces 341E: Candies Game
1515	Codeforces 341D: Iahub and Xors
1514	Codeforces 340E: Iahub and Permutations
1513	Codeforces 340D: Bubble Sort Graph
1512	Codeforces 340C: Tourist Problem
1511	Codeforces 340B: Maximal Area Quadrilateral
1510	Codeforces 340A: The Wall
1509	Codeforces 339E: Three Swaps
1508	Codeforces 339D: Xenia and Bit Operations
1507	Codeforces 339C: Xenia and Weights
1506	Codeforces 339B: Xenia and Ringroad
1505	Codeforces 339A: Helpful Maths
1504	Codeforces 338E: Optimize!
1503	Codeforces 338D: GCD Table
1502	Codeforces 337E: Divisor Tree

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

1551

Codeforces 350B: Resort

1550

Codeforces 350A: TL

1549

Codeforces 349B: Color the Fence

1548

Codeforces 349A: Cinema Line

1547

Codeforces 348E: Pilgrims

1546