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)
5801	Codeforces 1303E: Erase Subsequences
5800	Codeforces 1303D: Fill The Bag
5799	Codeforces 1303C: Perfect Keyboard
5798	Codeforces 1303B: National Project
5797	Codeforces 1303A: Erasing Zeroes
5796	Codeforces 1302J: Keep talking and nobody explodes -- hard
5795	Codeforces 1302I: Deja vu
5794	Codeforces 1302H: Who needs suffix structures?
5793	Codeforces 1302G: Keep talking and nobody explodes -- medium
5792	Codeforces 1302F: Keep talking and nobody explodes -- easy
5791	Codeforces 1302E: Amazing bitset
5790	Codeforces 1302D: Dijkstra
5789	Codeforces 1302C: Segment tree or Fenwick?
5788	Codeforces 1302B: DAG
5787	Codeforces 1302A: Nash equilibrium
5786	Codeforces 1301F: Super Jaber
5785	Codeforces 1301E: Nanosoft
5784	Codeforces 1301D: Time to Run
5783	Codeforces 1301C: Ayoub's function
5782	Codeforces 1301B: Motarack's Birthday
5781	Codeforces 1301A: Three Strings
5780	Codeforces 1300B: Assigning to Classes
5779	Codeforces 1300A: Non-zero
5778	Codeforces 1299E: So Mean
5777	Codeforces 1299D: Around the World
5776	Codeforces 1299C: Water Balance
5775	Codeforces 1299B: Aerodynamic
5774	Codeforces 1299A: Anu Has a Function
5773	Codeforces 1297I: Falling Blocks
5772	Codeforces 1297H: Paint the String
5771	Codeforces 1297G: M-numbers
5770	Codeforces 1297F: Movie Fan
5769	Codeforces 1297E: Modernization of Treeland
5768	Codeforces 1297D: Bonus Distribution
5767	Codeforces 1297C: Dream Team
5766	Codeforces 1297B: Cartoons
5765	Codeforces 1297A: Likes Display
5764	Codeforces 1296F: Berland Beauty
5763	Codeforces 1296E2: String Coloring (hard version)
5762	Codeforces 1296E1: String Coloring (easy version)
5761	Codeforces 1296D: Fight with Monsters
5760	Codeforces 1296C: Yet Another Walking Robot
5759	Codeforces 1296B: Food Buying
5758	Codeforces 1296A: Array with Odd Sum
5757	Codeforces 1295F: Good Contest
5756	Codeforces 1295E: Permutation Separation
5755	Codeforces 1295D: Same GCDs
5754	Codeforces 1295C: Obtain The String
5753	Codeforces 1295B: Infinite Prefixes
5752	Codeforces 1295A: Display The Number

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

5801

Codeforces 1303E: Erase Subsequences

5800

Codeforces 1303D: Fill The Bag

5799

Codeforces 1303C: Perfect Keyboard

5798

Codeforces 1303B: National Project

5797

Codeforces 1303A: Erasing Zeroes

5796