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)
11751	AtCoder ARC150: C. Path and Subsequence
11750	AtCoder ARC150: B. Make Divisible
11749	AtCoder ARC150: A. Continuous 1
11748	AtCoder ARC149: F. Rational Number System
11747	AtCoder ARC149: E. Sliding Window Sort
11746	AtCoder ARC149: D. Simultaneous Sugoroku
11745	AtCoder ARC149: C. Avoid Prime Sum
11744	AtCoder ARC149: B. Two LIS Sum
11743	AtCoder ARC149: A. Repdigit Number
11742	AtCoder ARC148: F. 998244353 → 1000000007
11741	AtCoder ARC148: E. ≥ K
11740	AtCoder ARC148: D. mod M Game
11739	AtCoder ARC148: C. Lights Out on Tree
11738	AtCoder ARC148: B. dp
11737	AtCoder ARC148: A. mod M
11736	AtCoder ARC147: F. Again ABC String
11735	AtCoder ARC147: E. Examination
11734	AtCoder ARC147: D. Sets Scores
11733	AtCoder ARC147: C. Min Diff Sum
11732	AtCoder ARC147: B. Swap to Sort
11731	AtCoder ARC147: A. Max Mod Min
11730	AtCoder ARC146: F. Simple Solitaire
11729	AtCoder ARC146: E. Simple Speed
11728	AtCoder ARC146: D. >=<
11727	AtCoder ARC146: C. Even XOR
11726	AtCoder ARC146: B. Plus and AND
11725	AtCoder ARC146: A. Three Cards
11724	AtCoder ARC145: F. Modulo Sum of Increasing Sequences
11723	AtCoder ARC145: E. Adjacent XOR
11722	AtCoder ARC145: D. Non Arithmetic Progression Set
11721	AtCoder ARC145: C. Split and Maximize
11720	AtCoder ARC145: B. AB Game
11719	AtCoder ARC145: A. AB Palindrome
11718	AtCoder ARC144: F. Arithmetic Sequence Nim
11717	AtCoder ARC144: E. GCD of Path Weights
11716	AtCoder ARC144: D. AND OR Equation
11715	AtCoder ARC144: C. K Derangement
11714	AtCoder ARC144: B. Gift Tax
11713	AtCoder ARC144: A. Digit Sum of 2x
11712	AtCoder ARC143: F. Counting Subsets
11711	AtCoder ARC143: E. Reversi
11710	AtCoder ARC143: D. Bridges
11709	AtCoder ARC143: C. Piles of Pebbles
11708	AtCoder ARC143: B. Counting Grids
11707	AtCoder ARC143: A. Three Integers
11706	AtCoder ARC142: F. Paired Wizards
11705	AtCoder ARC142: E. Pairing Wizards
11704	AtCoder ARC142: D. Deterministic Placing
11703	AtCoder ARC142: C. Tree Queries
11702	AtCoder ARC142: B. Unbalanced Squares

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

11751

AtCoder ARC150: C. Path and Subsequence

11750

AtCoder ARC150: B. Make Divisible

11749

AtCoder ARC150: A. Continuous 1

11748

AtCoder ARC149: F. Rational Number System

11747

AtCoder ARC149: E. Sliding Window Sort

11746