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)
9290 AtCoder ABC126: F. XOR Matching
9289 AtCoder ABC126: E. 1 or 2
9288 AtCoder ABC126: D. Even Relation
9287 AtCoder ABC126: C. Dice and Coin
9286 AtCoder ABC126: B. YYMM or MMYY
9285 AtCoder ABC126: A. Changing a Character
9284 AtCoder ABC125: D. Flipping Signs
9283 AtCoder ABC125: C. GCD on Blackboard
9282 AtCoder ABC125: B. Resale
9281 AtCoder ABC125: A. Biscuit Generator
9280 AtCoder ABC124: D. Handstand
9279 AtCoder ABC124: C. Coloring Colorfully
9278 AtCoder ABC124: B. Great Ocean View
9277 AtCoder ABC124: A. Buttons
9276 AtCoder ABC123: D. Cake 123
9275 AtCoder ABC123: C. Five Transportations
9274 AtCoder ABC123: B. Five Dishes
9273 AtCoder ABC123: A. Five Antennas
9272 AtCoder ABC122: D. We Like AGC
9271 AtCoder ABC122: C. GeT AC
9270 AtCoder ABC122: B. ATCoder
9269 AtCoder ABC122: A. Double Helix
9268 AtCoder ABC121: D. XOR World
9267 AtCoder ABC121: C. Energy Drink Collector
9266 AtCoder ABC121: B. Can you solve this?
9265 AtCoder ABC121: A. White Cells
9264 AtCoder ABC120: D. Decayed Bridges
9263 AtCoder ABC120: C. Unification
9262 AtCoder ABC120: B. K-th Common Divisor
9261 AtCoder ABC120: A. Favorite Sound
9260 AtCoder ABC119: D. Lazy Faith
9259 AtCoder ABC119: C. Synthetic Kadomatsu
9258 AtCoder ABC119: B. Digital Gifts
9257 AtCoder ABC119: A. Still TBD
9256 AtCoder ABC118: D. Match Matching
9255 AtCoder ABC118: C. Monsters Battle Royale
9254 AtCoder ABC118: B. Foods Loved by Everyone
9253 AtCoder ABC118: A. B +/- A
9252 AtCoder ABC117: D. XXOR
9251 AtCoder ABC117: C. Streamline
9250 AtCoder ABC117: B. Polygon
9249 AtCoder ABC117: A. Entrance Examination
9248 AtCoder ABC116: D. Various Sushi
9247 AtCoder ABC116: C. Grand Garden
9246 AtCoder ABC116: B. Collatz Problem
9245 AtCoder ABC116: A. Right Triangle
9244 AtCoder ABC115: D. Christmas
9243 AtCoder ABC115: C. Christmas Eve
9242 AtCoder ABC115: B. Christmas Eve Eve
9241 AtCoder ABC115: A. Christmas Eve Eve Eve
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