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)
2201	Codeforces 513F2: Scaygerboss
2200	Codeforces 513F1: Scaygerboss
2199	Codeforces 513E2: Subarray Cuts
2198	Codeforces 513E1: Subarray Cuts
2197	Codeforces 513D2: Constrained Tree
2196	Codeforces 513D1: Constrained Tree
2195	Codeforces 513C: Second price auction
2194	Codeforces 513B2: Permutations
2193	Codeforces 513B1: Permutations
2192	Codeforces 513A: Game
2191	Codeforces 512E: Fox And Polygon
2190	Codeforces 512D: Fox And Travelling
2189	Codeforces 510E: Fox And Dinner
2188	Codeforces 510D: Fox And Jumping
2187	Codeforces 510C: Fox And Names
2186	Codeforces 510B: Fox And Two Dots
2185	Codeforces 510A: Fox And Snake
2184	Codeforces 509F: Progress Monitoring
2183	Codeforces 509E: Pretty Song
2182	Codeforces 509D: Restoring Numbers
2181	Codeforces 509C: Sums of Digits
2180	Codeforces 509B: Painting Pebbles
2179	Codeforces 509A: Maximum in Table
2178	Codeforces 508E: Arthur and Brackets
2177	Codeforces 508D: Tanya and Password
2176	Codeforces 508C: Anya and Ghosts
2175	Codeforces 508B: Anton and currency you all know
2174	Codeforces 508A: Pasha and Pixels
2173	Codeforces 507E: Breaking Good
2172	Codeforces 507D: The Maths Lecture
2171	Codeforces 507C: Guess Your Way Out!
2170	Codeforces 507B: Amr and Pins
2169	Codeforces 507A: Amr and Music
2168	Codeforces 506E: Mr. Kitayuta's Gift
2167	Codeforces 506D: Mr. Kitayuta's Colorful Graph
2166	Codeforces 505E: Mr. Kitayuta vs. Bamboos
2165	Codeforces 505D: Mr. Kitayuta's Technology
2164	Codeforces 505C: Mr. Kitayuta, the Treasure Hunter
2163	Codeforces 505B: Mr. Kitayuta's Colorful Graph
2162	Codeforces 505A: Mr. Kitayuta's Gift
2161	Codeforces 504E: Misha and LCP on Tree
2160	Codeforces 504D: Misha and XOR
2159	Codeforces 501E: Misha and Palindrome Degree
2158	Codeforces 501D: Misha and Permutations Summation
2157	Codeforces 501C: Misha and Forest
2156	Codeforces 501B: Misha and Changing Handles
2155	Codeforces 501A: Contest
2154	Codeforces 500G: New Year Running
2153	Codeforces 500F: New Year Shopping
2152	Codeforces 500E: New Year Domino

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

2201

Codeforces 513F2: Scaygerboss

2200

Codeforces 513F1: Scaygerboss

2199

Codeforces 513E2: Subarray Cuts

2198

Codeforces 513E1: Subarray Cuts

2197

Codeforces 513D2: Constrained Tree

2196