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)
24435 Codeforces 1912C: Cactus Transformation
24434 Codeforces 1912B: Blueprint for Seating
24433 Codeforces 1912A: Accumulator Apex
24432 Codeforces 1910J: Two Colors
24431 Codeforces 1910I: Inverse Problem
24430 Codeforces 1910H: Sum of Digits of Sums
24429 Codeforces 1910G: Pool Records
24428 Codeforces 1910F: Build Railway Stations
24427 Codeforces 1910E: Maximum Sum Subarrays
24426 Codeforces 1910D: Remove and Add
24425 Codeforces 1910C: Poisonous Swamp
24424 Codeforces 1910B: Security Guard
24423 Codeforces 1910A: Username
24422 Codeforces 1909I: Short Permutation Problem
24421 Codeforces 1909H: Parallel Swaps Sort
24420 Codeforces 1909G: Pumping Lemma
24419 Codeforces 1909F2: Small Permutation Problem (Hard Version)
24418 Codeforces 1909F1: Small Permutation Problem (Easy Version)
24417 Codeforces 1909E: Multiple Lamps
24416 Codeforces 1909D: Split Plus K
24415 Codeforces 1909C: Heavy Intervals
24414 Codeforces 1909B: Make Almost Equal With Mod
24413 Codeforces 1909A: Distinct Buttons
24412 Codeforces 1907G: Lights
24411 Codeforces 1907F: Shift and Reverse
24410 Codeforces 1907E: Good Triples
24409 Codeforces 1907D: Jumping Through Segments
24408 Codeforces 1907C: Removal of Unattractive Pairs
24407 Codeforces 1907B: YetnotherrokenKeoard
24406 Codeforces 1907A: Rook
24405 Codeforces 1906M: Triangle Construction
24404 Codeforces 1906L: Palindromic Parentheses
24403 Codeforces 1906K: Deck-Building Game
24402 Codeforces 1906J: Count BFS Graph
24401 Codeforces 1906I: Contingency Plan 2
24400 Codeforces 1906H: Twin Friends
24399 Codeforces 1906G: Grid Game 2
24398 Codeforces 1906F: Maximize The Value
24397 Codeforces 1906E: Merge Not Sort
24396 Codeforces 1906D: Spaceship Exploration
24395 Codeforces 1906C: Cursed Game
24394 Codeforces 1906B: Button Pressing
24393 Codeforces 1906A: Easy As ABC
24392 Codeforces 1905F: Field Should Not Be Empty
24391 Codeforces 1905E: One-X
24390 Codeforces 1905D: Cyclic MEX
24389 Codeforces 1905C: Largest Subsequence
24388 Codeforces 1905B: Begginer's Zelda
24387 Codeforces 1905A: Constructive Problems
24386 Codeforces 1904F: Beautiful Tree
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