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)
9601	AtCoder ABC178: E. Dist Max
9600	AtCoder ABC178: D. Redistribution
9599	AtCoder ABC178: C. Ubiquity
9598	AtCoder ABC178: B. Product Max
9597	AtCoder ABC178: A. Not
9596	AtCoder ABC177: F. I hate Shortest Path Problem
9595	AtCoder ABC177: E. Coprime
9594	AtCoder ABC177: D. Friends
9593	AtCoder ABC177: C. Sum of product of pairs
9592	AtCoder ABC177: B. Substring
9591	AtCoder ABC177: A. Don't be late
9590	AtCoder ABC176: F. Brave CHAIN
9589	AtCoder ABC176: E. Bomber
9588	AtCoder ABC176: D. Wizard in Maze
9587	AtCoder ABC176: C. Step
9586	AtCoder ABC176: B. Multiple of 9
9585	AtCoder ABC176: A. Takoyaki
9584	AtCoder ABC175: F. Making Palindrome
9583	AtCoder ABC175: E. Picking Goods
9582	AtCoder ABC175: D. Moving Piece
9581	AtCoder ABC175: C. Walking Takahashi
9580	AtCoder ABC175: B. Making Triangle
9579	AtCoder ABC175: A. Rainy Season
9578	AtCoder ABC174: F. Range Set Query
9577	AtCoder ABC174: E. Logs
9576	AtCoder ABC174: D. Alter Altar
9575	AtCoder ABC174: C. Repsept
9574	AtCoder ABC174: B. Distance
9573	AtCoder ABC174: A. Air Conditioner
9572	AtCoder ABC173: F. Intervals on Tree
9571	AtCoder ABC173: E. Multiplication 4
9570	AtCoder ABC173: D. Chat in a Circle
9569	AtCoder ABC173: C. H and V
9568	AtCoder ABC173: B. Judge Status Summary
9567	AtCoder ABC173: A. Payment
9566	AtCoder ABC172: F. Unfair Nim
9565	AtCoder ABC172: E. NEQ
9564	AtCoder ABC172: D. Sum of Divisors
9563	AtCoder ABC172: C. Tsundoku
9562	AtCoder ABC172: B. Minor Change
9561	AtCoder ABC172: A. Calc
9560	AtCoder ABC171: F. Strivore
9559	AtCoder ABC171: E. Red Scarf
9558	AtCoder ABC171: D. Replacing
9557	AtCoder ABC171: C. One Quadrillion and One Dalmatians
9556	AtCoder ABC171: B. Mix Juice
9555	AtCoder ABC171: A. αlphabet
9554	AtCoder ABC170: F. Pond Skater
9553	AtCoder ABC170: E. Smart Infants
9552	AtCoder ABC170: D. Not Divisible

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

9601

AtCoder ABC178: E. Dist Max

9600

AtCoder ABC178: D. Redistribution

9599

AtCoder ABC178: C. Ubiquity

9598

AtCoder ABC178: B. Product Max

9597

AtCoder ABC178: A. Not

9596