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)
3451	Codeforces 809E: Surprise me!
3450	Codeforces 809D: Hitchhiking in the Baltic States
3449	Codeforces 809C: Find a car
3448	Codeforces 809B: Glad to see you!
3447	Codeforces 809A: Do you want a date?
3446	Codeforces 808G: Anthem of Berland
3445	Codeforces 808F: Card Game
3444	Codeforces 808E: Selling Souvenirs
3443	Codeforces 808D: Array Division
3442	Codeforces 808C: Tea Party
3441	Codeforces 808B: Average Sleep Time
3440	Codeforces 808A: Lucky Year
3439	Codeforces 807B: T-Shirt Hunt
3438	Codeforces 807A: Is it rated?
3437	Codeforces 805B: 3-palindrome
3436	Codeforces 805A: Fake NP
3435	Codeforces 804F: Fake bullions
3434	Codeforces 804E: The same permutation
3433	Codeforces 804D: Expected diameter of a tree
3432	Codeforces 804C: Ice cream coloring
3431	Codeforces 804B: Minimum number of steps
3430	Codeforces 804A: Find Amir
3429	Codeforces 803G: Periodic RMQ Problem
3428	Codeforces 803F: Coprime Subsequences
3427	Codeforces 803E: Roma and Poker
3426	Codeforces 803D: Magazine Ad
3425	Codeforces 803C: Maximal GCD
3424	Codeforces 803B: Distances to Zero
3423	Codeforces 803A: Maximal Binary Matrix
3422	Codeforces 802O: April Fools' Problem (hard)
3421	Codeforces 802N: April Fools' Problem (medium)
3420	Codeforces 802M: April Fools' Problem (easy)
3419	Codeforces 802L: Send the Fool Further! (hard)
3418	Codeforces 802K: Send the Fool Further! (medium)
3417	Codeforces 802J: Send the Fool Further! (easy)
3416	Codeforces 802I: Fake News (hard)
3415	Codeforces 802H: Fake News (medium)
3414	Codeforces 802G: Fake News (easy)
3413	Codeforces 802F: Marmots (hard)
3412	Codeforces 802E: Marmots (medium)
3411	Codeforces 802D: Marmots (easy)
3410	Codeforces 802C: Heidi and Library (hard)
3409	Codeforces 802B: Heidi and Library (medium)
3408	Codeforces 802A: Heidi and Library (easy)
3407	Codeforces 801B: Valued Keys
3406	Codeforces 801A: Vicious Keyboard
3405	Codeforces 799G: Cut the pie
3404	Codeforces 799F: Beautiful fountains rows
3403	Codeforces 799E: Aquarium decoration
3402	Codeforces 799D: Field expansion

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

3451

Codeforces 809E: Surprise me!

3450

Codeforces 809D: Hitchhiking in the Baltic States

3449

Codeforces 809C: Find a car

3448

Codeforces 809B: Glad to see you!

3447

Codeforces 809A: Do you want a date?

3446