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.

Reset

Need help searching? Click for format/examples of problems
  • 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)
23804 DMOJ NOIP '08 P1 - Silly Monkey
23803 DMOJ NOIP '07 P4 - Core of a Tree Net
23802 DMOJ NOIP '07 P3 - Removing Numbers from Matrix
23801 DMOJ NOIP '07 P2 - Expanding Strings
23800 DMOJ NOIP '07 P1 - Counting Numbers
23799 DMOJ IOI '04 P3 - Polygon
19827 DMOJ New Year's '19 P8 - Best Hat in Town II
19826 DMOJ New Year's '19 P7 - The Order of the Fox
19825 DMOJ New Year's '19 P6 - Buffer Zone
19824 DMOJ New Year's '19 P5 - Best Hat in Town
19823 DMOJ New Year's '19 P4 - A Button Challenge
19822 DMOJ New Year's '19 P3 - Santa's Journey
19821 DMOJ New Year's '19 P2 - Ball Sculpture
19820 DMOJ New Year's '19 P1 - Snowball Fight
19819 DMOJ New Year's '18 P8 - Snowy Streets
19818 DMOJ New Year's '18 P7 - Tree of Life
19817 DMOJ New Year's '18 P6 - Old Christmas Lights II
19816 DMOJ New Year's '18 P5 - Hanoi Heuristics
19815 DMOJ New Year's '18 P4 - The Polar Express
19814 DMOJ New Year's '18 P3 - World Domination Fun
19813 DMOJ New Year's '18 P2 - Mimi and Christmas Cake
19812 DMOJ New Year's '18 P1 - Happy New Year!
19811 DMOJ New Year's '17 P8 - Boxen in Boxen
19810 DMOJ New Year's '17 P7 - Santa's Deliveries
19809 DMOJ New Year's '17 P6 - Christmas Cards
19808 DMOJ New Year's '17 P5 - The Christmas Swap
19807 DMOJ New Year's '17 P4 - Christmas Cozonac
19806 DMOJ New Year's '17 P3 - Fibonacci Presents
19805 DMOJ New Year's '17 P2 - Peter's Escape
19804 DMOJ New Year's '17 P1 - Mr. N and Presents
19803 DMOJ New Year's '16 P8 - S-NO-wall
19802 DMOJ New Year's '16 P7 - Old Christmas Lights
19801 DMOJ New Year's '16 P6 - Cake Balancing
19800 DMOJ New Year's '16 P5 - Eggnog Dilemma
19799 DMOJ New Year's '16 P4 - DIY Christmas Tree
19798 DMOJ New Year's '16 P3 - Arithmetic Snowman
19797 DMOJ New Year's '16 P2 - The 365 Days of Christmas
19796 DMOJ New Year's '16 P1 - Late Christmas Shopping
19795 DMOJ New Year's '15 P6 - Tiles
19794 DMOJ New Year's '15 P5 - Message to Mars
19793 DMOJ New Year's '15 P4 - Leftover Eggnog
19792 DMOJ New Year's '15 P3 - Gift Wrap
19791 DMOJ New Year's '15 P2 - Food Selection
19790 DMOJ New Year's '15 P1 - Invitation Devastation
19789 DMOJ Yet Another Contest 6 P6 - No More Snakes and Ladders
19788 DMOJ Yet Another Contest 6 P5 - No More Coyotes
19787 DMOJ Yet Another Contest 6 P4 - No More Nails!
19786 DMOJ Yet Another Contest 6 P3 - No More Cell Phone Messaging
19785 DMOJ Yet Another Contest 6 P2 - No More Telemarketers
19784 DMOJ Yet Another Contest 6 P1 - No More Separation
View links to all pages 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101

AboutPrivacy NoticeRulesProblems listJournalYour profileGitHub

Moon Symbol icon by Icons8Sun icon by Icons8 • Emojis from Twemoji by Twitter under CC by 4.0