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)
751	Codeforces 160B: Unlucky Ticket
750	Codeforces 160A: Twins
749	Codeforces 159E: Zebra Tower
748	Codeforces 159D: Palindrome pairs
747	Codeforces 159C: String Manipulation 1.0
746	Codeforces 159B: Matchmaker
745	Codeforces 159A: Friends or Not
744	Codeforces 158E: Phone Talks
743	Codeforces 158D: Ice Sculptures
742	Codeforces 158C: Cd and pwd commands
741	Codeforces 158B: Taxi
740	Codeforces 158A: Next Round
739	Codeforces 157B: Trace
738	Codeforces 157A: Game Outcome
737	Codeforces 156E: Mrs. Hudson's Pancakes
736	Codeforces 156D: Clues
735	Codeforces 156C: Cipher
734	Codeforces 156B: Suspects
733	Codeforces 156A: Message
732	Codeforces 155B: Combination
731	Codeforces 155A: I_love_\%username\%
730	Codeforces 154E: Martian Colony
729	Codeforces 154D: Flatland Fencing
728	Codeforces 154C: Double Profiles
727	Codeforces 154B: Colliders
726	Codeforces 154A: Hometask
725	Codeforces 153E: Euclidean Distance
724	Codeforces 153D: Date Change
723	Codeforces 153C: Caesar Cipher
722	Codeforces 153B: Binary notation
721	Codeforces 153A: A + B
720	Codeforces 152E: Garden
719	Codeforces 152D: Frames
718	Codeforces 152C: Pocket Book
717	Codeforces 152B: Steps
716	Codeforces 152A: Marks
715	Codeforces 151B: Phone Numbers
714	Codeforces 151A: Soft Drinking
713	Codeforces 150E: Freezing with Style
712	Codeforces 150D: Mission Impassable
711	Codeforces 150C: Smart Cheater
710	Codeforces 150B: Quantity of Strings
709	Codeforces 150A: Win or Freeze
708	Codeforces 149E: Martian Strings
707	Codeforces 149D: Coloring Brackets
706	Codeforces 149C: Division into Teams
705	Codeforces 149B: Martian Clock
704	Codeforces 149A: Business trip
703	Codeforces 148E: Porcelain
702	Codeforces 148D: Bag of mice

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

751

Codeforces 160B: Unlucky Ticket

750

Codeforces 160A: Twins

749

Codeforces 159E: Zebra Tower

748

Codeforces 159D: Palindrome pairs

747

Codeforces 159C: String Manipulation 1.0

746