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)
9501	AtCoder ABC162: A. Lucky 7
9500	AtCoder ABC161: F. Division or Subtraction
9499	AtCoder ABC161: E. Yutori
9498	AtCoder ABC161: D. Lunlun Number
9497	AtCoder ABC161: C. Replacing Integer
9496	AtCoder ABC161: B. Popular Vote
9495	AtCoder ABC161: A. ABC Swap
9494	AtCoder ABC160: F. Distributing Integers
9493	AtCoder ABC160: E. Red and Green Apples
9492	AtCoder ABC160: D. Line++
9491	AtCoder ABC160: C. Traveling Salesman around Lake
9490	AtCoder ABC160: B. Golden Coins
9489	AtCoder ABC160: A. Coffee
9488	AtCoder ABC159: F. Knapsack for All Segments
9487	AtCoder ABC159: E. Dividing Chocolate
9486	AtCoder ABC159: D. Banned K
9485	AtCoder ABC159: C. Maximum Volume
9484	AtCoder ABC159: B. String Palindrome
9483	AtCoder ABC159: A. The Number of Even Pairs
9482	AtCoder ABC158: F. Removing Robots
9481	AtCoder ABC158: E. Divisible Substring
9480	AtCoder ABC158: D. String Formation
9479	AtCoder ABC158: C. Tax Increase
9478	AtCoder ABC158: B. Count Balls
9477	AtCoder ABC158: A. Station and Bus
9476	AtCoder ABC157: F. Yakiniku Optimization Problem
9475	AtCoder ABC157: E. Simple String Queries
9474	AtCoder ABC157: D. Friend Suggestions
9473	AtCoder ABC157: C. Guess The Number
9472	AtCoder ABC157: B. Bingo
9471	AtCoder ABC157: A. Duplex Printing
9470	AtCoder ABC156: F. Modularness
9469	AtCoder ABC156: E. Roaming
9468	AtCoder ABC156: D. Bouquet
9467	AtCoder ABC156: C. Rally
9466	AtCoder ABC156: B. Digits
9465	AtCoder ABC156: A. Beginner
9464	AtCoder ABC155: F. Perils in Parallel
9463	AtCoder ABC155: E. Payment
9462	AtCoder ABC155: D. Pairs
9461	AtCoder ABC155: C. Poll
9460	AtCoder ABC155: B. Papers, Please
9459	AtCoder ABC155: A. Poor
9458	AtCoder ABC154: F. Many Many Paths
9457	AtCoder ABC154: E. Almost Everywhere Zero
9456	AtCoder ABC154: D. Dice in Line
9455	AtCoder ABC154: C. Distinct or Not
9454	AtCoder ABC154: B. I miss you...
9453	AtCoder ABC154: A. Remaining Balls
9452	AtCoder ABC153: F. Silver Fox vs Monster

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

9501

AtCoder ABC162: A. Lucky 7

9500

AtCoder ABC161: F. Division or Subtraction

9499

AtCoder ABC161: E. Yutori

9498

AtCoder ABC161: D. Lunlun Number

9497

AtCoder ABC161: C. Replacing Integer

9496