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)
11601	AtCoder ARC125: C. LIS to Original Sequence
11600	AtCoder ARC125: B. Squares
11599	AtCoder ARC125: A. Dial Up
11598	AtCoder ARC124: F. Chance Meeting
11597	AtCoder ARC124: E. Pass to Next
11596	AtCoder ARC124: D. Yet Another Sorting Problem
11595	AtCoder ARC124: C. LCM of GCDs
11594	AtCoder ARC124: B. XOR Matching 2
11593	AtCoder ARC124: A. LR Constraints
11592	AtCoder ARC123: F. Insert Addition
11591	AtCoder ARC123: E. Training
11590	AtCoder ARC123: D. Inc, Dec - Decomposition
11589	AtCoder ARC123: C. 1, 2, 3 - Decomposition
11588	AtCoder ARC123: B. Increasing Triples
11587	AtCoder ARC123: A. Arithmetic Sequence
11586	AtCoder ARC122: F. Domination
11585	AtCoder ARC122: E. Increasing LCMs
11584	AtCoder ARC122: D. XOR Game
11583	AtCoder ARC122: C. Calculator
11582	AtCoder ARC122: B. Insurance
11581	AtCoder ARC122: A. Many Formulae
11580	AtCoder ARC121: F. Logical Operations on Tree
11579	AtCoder ARC121: E. Directed Tree
11578	AtCoder ARC121: D. 1 or 2
11577	AtCoder ARC121: C. Odd Even Sort
11576	AtCoder ARC121: B. RGB Matching
11575	AtCoder ARC121: A. 2nd Greatest Distance
11574	AtCoder ARC120: F2. Wine Thief
11573	AtCoder ARC120: F. Wine Thief
11572	AtCoder ARC120: E. 1D Party
11571	AtCoder ARC120: D. Bracket Score 2
11570	AtCoder ARC120: C. Swaps 2
11569	AtCoder ARC120: B. Uniformly Distributed
11568	AtCoder ARC120: A. Max Add
11567	AtCoder ARC119: F. AtCoder Express 3
11566	AtCoder ARC119: E. Pancakes
11565	AtCoder ARC119: D. Grid Repainting 3
11564	AtCoder ARC119: C. ARC Wrecker 2
11563	AtCoder ARC119: B. Electric Board
11562	AtCoder ARC119: A. 119 × 2^23 + 1
11561	AtCoder ARC118: F. Growth Rate
11560	AtCoder ARC118: E. Avoid Permutations
11559	AtCoder ARC118: D. Hamiltonian Cycle
11558	AtCoder ARC118: C. Coprime Set
11557	AtCoder ARC118: B. Village of M People
11556	AtCoder ARC118: A. Tax Included Price
11555	AtCoder ARC117: F. Gateau
11554	AtCoder ARC117: E. Zero-Sum Ranges 2
11553	AtCoder ARC117: D. Miracle Tree
11552	AtCoder ARC117: C. Tricolor Pyramid

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

11601

AtCoder ARC125: C. LIS to Original Sequence

11600

AtCoder ARC125: B. Squares

11599

AtCoder ARC125: A. Dial Up

11598

AtCoder ARC124: F. Chance Meeting

11597

AtCoder ARC124: E. Pass to Next

11596