Starlight

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)
23909 Codeforces 1872A: Two Vessels
23905 Codeforces 1866M: Mighty Rock Tower
23904 Codeforces 1866L: Lihmuf Balling
23903 Codeforces 1866K: Keen Tree Calculation
23902 Codeforces 1866J: Jackets and Packets
23901 Codeforces 1866I: Imagination Castle
23900 Codeforces 1866H: Happy Sets
23899 Codeforces 1866G: Grouped Carriages
23898 Codeforces 1866F: Freak Joker Process
23897 Codeforces 1866E: Elevators of Tamem
23896 Codeforces 1866D: Digital Wallet
23895 Codeforces 1866C: Completely Searching for Inversions
23894 Codeforces 1866B: Battling with Numbers
23893 Codeforces 1866A: Ambitious Kid
23881 Codeforces 1861F: Four Suits
23880 Codeforces 1861E: Non-Intersecting Subpermutations
23879 Codeforces 1861D: Sorting By Multiplication
23878 Codeforces 1861C: Queries for the Array
23877 Codeforces 1861B: Two Binary Strings
23876 Codeforces 1861A: Prime Deletion
23875 Codeforces 1863I: Redundant Routes
23874 Codeforces 1863H: Goldberg Machine 3
23873 Codeforces 1863G: Swaps
23872 Codeforces 1863F: Divide, XOR, and Conquer
23871 Codeforces 1863E: Speedrun
23870 Codeforces 1863D: Two-Colored Dominoes
23869 Codeforces 1863C: MEX Repetition
23868 Codeforces 1863B: Split Sort
23867 Codeforces 1863A: Channel
23849 Codeforces 1864I: Future Dominators
23848 Codeforces 1864H: Asterism Stream
23847 Codeforces 1864G: Magic Square
23846 Codeforces 1864F: Exotic Queries
23845 Codeforces 1864E: Guess Game
23844 Codeforces 1864D: Matrix Cascade
23843 Codeforces 1864C: Divisor Chain
23842 Codeforces 1864B: Swap and Reverse
23841 Codeforces 1864A: Increasing and Decreasing
23838 Codeforces 1862G: The Great Equalizer
23837 Codeforces 1862F: Magic Will Save the World
23836 Codeforces 1862E: Kolya and Movie Theatre
23835 Codeforces 1862D: Ice Cream Balls
23834 Codeforces 1862C: Flower City Fence
23833 Codeforces 1862B: Sequence Game
23832 Codeforces 1862A: Gift Carpet
23812 Codeforces 1860F: Evaluate RBS
23811 Codeforces 1860E: Fast Travel Text Editor
23810 Codeforces 1860D: Balanced String
23809 Codeforces 1860C: Game on Permutation
23808 Codeforces 1860B: Fancy Coins
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192

About • Privacy Notice • Rules • Problems list • Journal • Your profile • GitHub

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