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Over 20,000 problems available: AMC 8/10/12 and AIME problems from 2010-2024; USAJMO/USAMO problems from 2002-2024; USACO problems from 2014 to 2024 (all divisions); all Codeforces, AtCoder and DMOJ problems. If you leave the search field blank, it returns all problems with the specified type.

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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)
50 Codeforces 12A: Super Agent
49 Codeforces 11E: Forward, march!
48 Codeforces 11D: A Simple Task
47 Codeforces 11C: How Many Squares?
46 Codeforces 11B: Jumping Jack
45 Codeforces 11A: Increasing Sequence
44 Codeforces 10E: Greedy Change
43 Codeforces 10D: LCIS
42 Codeforces 10C: Digital Root
41 Codeforces 10B: Cinema Cashier
40 Codeforces 10A: Power Consumption Calculation
39 Codeforces 9E: Interestring graph and Apples
38 Codeforces 9D: How many trees?
37 Codeforces 9C: Hexadecimal's Numbers
36 Codeforces 9B: Running Student
35 Codeforces 9A: Die Roll
34 Codeforces 8E: Beads
33 Codeforces 8D: Two Friends
32 Codeforces 8C: Looking for Order
31 Codeforces 8B: Obsession with Robots
30 Codeforces 8A: Train and Peter
29 Codeforces 7E: Defining Macros
28 Codeforces 7D: Palindrome Degree
27 Codeforces 7C: Line
26 Codeforces 7B: Memory Manager
25 Codeforces 7A: Kalevitch and Chess
24 Codeforces 6E: Exposition
23 Codeforces 6D: Lizards and Basements 2
22 Codeforces 6C: Alice, Bob and Chocolate
21 Codeforces 6B: President's Office
20 Codeforces 6A: Triangle
19 Codeforces 5E: Bindian Signalizing
18 Codeforces 5D: Follow Traffic Rules
17 Codeforces 5C: Longest Regular Bracket Sequence
16 Codeforces 5B: Center Alignment
15 Codeforces 5A: Chat Servers Outgoing Traffic
14 Codeforces 4D: Mysterious Present
13 Codeforces 4C: Registration System
12 Codeforces 4B: Before an Exam
11 Codeforces 4A: Watermelon
10 Codeforces 3D: Least Cost Bracket Sequence
9 Codeforces 3C: Tic-tac-toe
8 Codeforces 3B: Lorry
7 Codeforces 3A: Shortest path of the king
6 Codeforces 2C: Commentator problem
5 Codeforces 2B: The least round way
4 Codeforces 2A: Winner
3 Codeforces 1C: Ancient Berland Circus
2 Codeforces 1B: Spreadsheet
1 Codeforces 1A: Theatre Square
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