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)
7851	Codeforces 1692G: 2^Sort
7850	Codeforces 1692F: 3SUM
7849	Codeforces 1692E: Binary Deque
7848	Codeforces 1692D: The Clock
7847	Codeforces 1692C: Where's the Bishop?
7846	Codeforces 1692B: All Distinct
7845	Codeforces 1692A: Marathon
7844	Codeforces 1691F: K-Set Tree
7843	Codeforces 1691E: Number of Groups
7842	Codeforces 1691D: Max GEQ Sum
7841	Codeforces 1691C: Sum of Substrings
7840	Codeforces 1691B: Shoe Shuffling
7839	Codeforces 1691A: Beat The Odds
7838	Codeforces 1690G: Count the Trains
7837	Codeforces 1690F: Shifting String
7836	Codeforces 1690E: Price Maximization
7835	Codeforces 1690D: Black and White Stripe
7834	Codeforces 1690C: Restoring the Duration of Tasks
7833	Codeforces 1690B: Array Decrements
7832	Codeforces 1690A: Print a Pedestal (Codeforces logo?)
7831	Codeforces 1689E: ANDfinity
7830	Codeforces 1689D: Lena and Matrix
7829	Codeforces 1689C: Infected Tree
7828	Codeforces 1689B: Mystic Permutation
7827	Codeforces 1689A: Lex String
7826	Codeforces 1688C: Manipulating History
7825	Codeforces 1688B: Patchouli's Magical Talisman
7824	Codeforces 1688A: Cirno's Perfect Bitmasks Classroom
7823	Codeforces 1687F: Koishi's Unconscious Permutation
7822	Codeforces 1687E: Become Big For Me
7821	Codeforces 1687D: Cute number
7820	Codeforces 1687C: Sanae and Giant Robot
7819	Codeforces 1687B: Railway System
7818	Codeforces 1687A: The Enchanted Forest
7817	Codeforces 1686B: Odd Subarrays
7816	Codeforces 1686A: Everything Everywhere All But One
7815	Codeforces 1685E: The Ultimate LIS Problem
7814	Codeforces 1685D2: Permutation Weight (Hard Version)
7813	Codeforces 1685D1: Permutation Weight (Easy Version)
7812	Codeforces 1685C: Bring Balance
7811	Codeforces 1685B: Linguistics
7810	Codeforces 1685A: Circular Local MiniMax
7809	Codeforces 1684H: Hard Cut
7808	Codeforces 1684G: Euclid Guess
7807	Codeforces 1684F: Diverse Segments
7806	Codeforces 1684E: MEX vs DIFF
7805	Codeforces 1684D: Traps
7804	Codeforces 1684C: Column Swapping
7803	Codeforces 1684B: Z mod X = C
7802	Codeforces 1684A: Digit Minimization

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

7851

Codeforces 1692G: 2^Sort

7850

Codeforces 1692F: 3SUM

7849

Codeforces 1692E: Binary Deque

7848

Codeforces 1692D: The Clock

7847

Codeforces 1692C: Where's the Bishop?

7846