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Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 5975 | Tournament | bitmasks brute force dfs and similar greedy | Statement | B | Codeforces Beta Round 27 (Codeforces format, Div. 2) {27} | PROGRAMMING | Codeforces Beta #27 - Tutorial | 2000 | |
| 19682 | Lucky Numbers (easy) | binary search bitmasks brute force | Statement | B | Codeforces Beta Round 77 (Div. 2 Only) {96} | PROGRAMMING | Codeforces Beta Round #77 (Div. 2 Only) Question A - D | 1400 | |
| 386 | Robot in Basement | bitmasks brute force implementation | Statement | D | Yandex.Algorithm 2011: Finals {97} | PROGRAMMING | Финал Яндекс.Алгоритм: разбор A-B | 2600 | |
| 4320 | PFAST Inc. | bitmasks brute force graphs | Statement | B | Codeforces Beta Round 86 (Div. 2 Only) {114} | PROGRAMMING | Codeforces Beta Round #86 Editorial | 1500 | |
| 9970 | Compatible Numbers | bitmasks brute force dfs and similar dp | Statement | E | Codeforces Round 112 (Div. 2) {165} | PROGRAMMING | Codeforces Round #112 (Div. 2) Tutorial | 2100 | |
| 493 | Brand New Problem | bitmasks brute force dp | Statement | D | Codeforces Round 127 (Div. 1) {201} | PROGRAMMING | 2500 | ||
| 20132 | LLPS | binary search bitmasks brute force greedy implementation strings | Statement | A | Codeforces Round 127 (Div. 2) {202} | PROGRAMMING | 900 | ||
| 282 | Bitonix' Patrol | bitmasks brute force combinatorics dfs and similar math | Statement | D | Codeforces Round 134 (Div. 1) {217} | PROGRAMMING | Editorial for Codeforces Round #134 | 2800 | |
| 4973 | Undoubtedly Lucky Numbers | bitmasks brute force dfs and similar | Statement | B | Codeforces Round 150 (Div. 2) {244} | PROGRAMMING | Editorial for Codeforces Round #150 | 1600 | |
| 1888 | Network Mask | *special bitmasks brute force implementation | Statement | C | Croc Champ 2013 - Qualification Round {291} | PROGRAMMING | 2100 | ||
| 2273 | Characteristics of Rectangles | binary search bitmasks brute force implementation sortings | Statement | D | Codeforces Round 194 (Div. 1) {333} | PROGRAMMING | Codeforces Round 194 — Editoral | 2100 | |
| 1301 | Summer Earnings | binary search bitmasks brute force geometry sortings | Statement | E | Codeforces Round 194 (Div. 1) {333} | PROGRAMMING | Codeforces Round 194 — Editoral | 2400 | |
| 1683 | New Year Letter | bitmasks brute force dp | Statement | D | Good Bye 2013 {379} | PROGRAMMING | Tutorial Good Bye 2013 | 2000 | |
| 4748 | Roman and Numbers | bitmasks brute force combinatorics dp number theory | Statement | D | Codeforces Round 235 (Div. 2) {401} | PROGRAMMING | Codeforces Round #235 (Div. 2) — Tutorial | 2000 | |
| 2364 | Borya and Hanabi | bitmasks brute force implementation | Statement | A | Codeforces Round 253 (Div. 1) {442} | PROGRAMMING | Codeforces #253 editorial | 2000 | |
| 5580 | Little Pony and Harmony Chest | bitmasks brute force dp | Statement | B | Codeforces Round 259 (Div. 1) {453} | PROGRAMMING | Codeforces Round #259 Editorial | 2200 | |
| 43745 | Fedor and New Game | bitmasks brute force constructive algorithms implementation | Statement | B | Codeforces Round 267 (Div. 2) {467} | PROGRAMMING | Разбор задач | 1200 | |
| 507 | Design Tutorial: Increase the Constraints | bitmasks data structures fft | Statement | G | Codeforces Round 270 {472} | PROGRAMMING | Editorial | 2800 | |
| 38059 | Dreamoon and WiFi | bitmasks brute force combinatorics dp math probabilities | Statement | B | Codeforces Round 272 (Div. 2) {476} | PROGRAMMING | 1300 | ||
| 6537 | Fox And Jumping | bitmasks brute force dp math | Statement | D | Codeforces Round 290 (Div. 2) {510} | PROGRAMMING | Codeforces Round #290 Editorial | 2100 | |
| 4386 | Anya and Cubes | binary search bitmasks brute force dp math meet-in-the-middle | Statement | E | Codeforces Round 297 (Div. 2) {525} | PROGRAMMING | Codeforces Round #297 (Div.2) Editorial | 2200 | |
| 2987 | Fuzzy Search | bitmasks brute force fft | Statement | D | Codeforces Round 296 (Div. 1) {528} | PROGRAMMING | Codeforces Round #296 Editorial | 2500 | |
| 27065 | Tavas and SaDDas | bitmasks brute force combinatorics implementation | Statement | B | Codeforces Round 299 (Div. 2) {535} | PROGRAMMING | Codeforces Round #299 Editorial | 1100 | |
| 28678 | Preparing Olympiad | bitmasks brute force | Statement | B | Codeforces Round 306 (Div. 2) {550} | PROGRAMMING | Разбор задач Codeforces Round #306 (Div. 2) | 1500 | |
| 245 | Party | bitmasks brute force graph matchings | Statement | C | Bubble Cup 8 - Finals [Online Mirror] {575} | PROGRAMMING | Bubble Cup finals 2015 Results and Editorial | 2800 | |
| 4932 | Three Logos | bitmasks brute force constructive algorithms geometry implementation math | Statement | D | Codeforces Round 322 (Div. 2) {581} | PROGRAMMING | Codeforces Round #322 (Div.2) Editorial | 1700 | |
| 11263 | New Year and Old Property | bitmasks brute force implementation | Statement | B | Good Bye 2015 {611} | PROGRAMMING | Tutorial | 1300 | |
| 2633 | Binary Table | bitmasks brute force divide and conquer dp fft math | Statement | C | CROC 2016 - Final Round [Private, For Onsite Finalists Only] {662} | PROGRAMMING | Editorial for CROC 2016 Finals and Codeforces Round #347 | 2800 | |
| 681 | Travelling Through the Snow Queen's Kingdom | bitmasks brute force divide and conquer graphs | Statement | E | Codeforces Round 359 (Div. 1) {685} | PROGRAMMING | Codeforces Round #359 Editorial | 2700 | |
| 1659 | Vladik and cards | binary search bitmasks brute force dp | Statement | E | Codeforces Round 384 (Div. 2) {743} | PROGRAMMING | Codeforces Round #384 Editorial | 2300 | |
| 1370 | Hongcow Buys a Deck of Cards | bitmasks brute force dp | Statement | C | Codeforces Round 385 (Div. 1) {744} | PROGRAMMING | Codeforces Round #385 Editorial | 2500 | |
| 632 | New Year and Binary Tree Paths | bitmasks brute force combinatorics dp | Statement | G | Good Bye 2016 {750} | PROGRAMMING | Good Bye 2016 — hints and codes | 3100 | |
| 620 | Dasha and cyclic table | bitmasks brute force fft strings trees | Statement | E | Codeforces Round 390 (Div. 2) {754} | PROGRAMMING | 2800 | ||
| 2574 | k-Interesting Pairs Of Integers | *special bitmasks brute force meet-in-the-middle | Statement | D | VK Cup 2017 - Qualification 1 {769} | PROGRAMMING | Tutorial | 1800 | |
| 2551 | Bitwise Formula | bitmasks brute force dfs and similar expression parsing implementation | Statement | B | Codeforces Round 402 (Div. 1) {778} | PROGRAMMING | Codeforces Round #402, Editorial | 2000 | |
| 5576 | Sagheer, the Hausmeister | bitmasks brute force dp | Statement | B | Codeforces Round 417 (Div. 2) {812} | PROGRAMMING | [Editorial] Codeforces Round #417 (Div. 2) | 1600 | |
| 577 | Random Elections | bitmasks brute force divide and conquer fft math | Statement | E | Codeforces Round 432 (Div. 1, based on IndiaHacks Final Round 2017) {850} | PROGRAMMING | Codeforces Round #432 editorial | 2800 | |
| 163 | Hex Dyslexia | bitmasks brute force dp graphs | Statement | E | MemSQL Start[c]UP 3.0 - Round 2 (onsite finalists) {865} | PROGRAMMING | MemSQL Start[c]UP 3.0 Round 2 Editorial | 2700 | |
| 81 | Egg Roulette | bitmasks brute force divide and conquer math meet-in-the-middle | Statement | F | MemSQL Start[c]UP 3.0 - Round 2 (onsite finalists) {865} | PROGRAMMING | MemSQL Start[c]UP 3.0 Round 2 Editorial | 3300 | |
| 5063 | Qualification Rounds | bitmasks brute force constructive algorithms dp | Statement | C | Codeforces Round 438 by Sberbank and Barcelona Bootcamp (Div. 1 + Div. 2 combined) {868} | PROGRAMMING | 55046 | 1500 | |
| 1029 | Huge Strings | bitmasks brute force dp implementation strings | Statement | D | Codeforces Round 438 by Sberbank and Barcelona Bootcamp (Div. 1 + Div. 2 combined) {868} | PROGRAMMING | 55046 | 2100 | |
| 1564 | Party | bitmasks brute force dp graphs | Statement | C | Codeforces Round 454 (Div. 1, based on Technocup 2018 Elimination Round 4) {906} | PROGRAMMING | Editorial Codeforces Round 454 (and Technocup 2018 — Elimination Round 4) | 2300 | |
| 2599 | Substrings in a String | bitmasks brute force data structures string suffix structures strings | Statement | F | Codecraft-18 and Codeforces Round 458 (Div. 1 + Div. 2, combined) {914} | PROGRAMMING | Tutorial | 2900 | |
| 2060 | List Of Integers | binary search bitmasks brute force combinatorics math number theory | Statement | G | Educational Codeforces Round 37 (Rated for Div. 2) {920} | PROGRAMMING | T | 2300 | |
| 5660 | Chessboard | bitmasks brute force implementation | Statement | C | Educational Codeforces Round 41 (Rated for Div. 2) {961} | PROGRAMMING | Educational Codeforces Round 41 Editorial | 1400 | |
| 2263 | Kuro and GCD and XOR and SUM | binary search bitmasks brute force data structures dp dsu greedy math number theory strings trees | Statement | D | Codeforces Round 482 (Div. 2) {979} | PROGRAMMING | 1750.0 | Codeforces Round #482 (Div. 2) Editorial | 2200 |
| 2058 | Open Communication | bitmasks brute force | Statement | B | Codeforces Round 488 by NEAR (Div. 1) {993} | PROGRAMMING | Codeforces Round #488 editorial | 1900 | |
| 1838 | Careful Maneuvering | bitmasks brute force geometry | Statement | C | Codeforces Round 488 by NEAR (Div. 1) {993} | PROGRAMMING | Codeforces Round #488 editorial | 2100 | |
| 7247 | Xor-Paths | bitmasks brute force dp meet-in-the-middle | Statement | F | Codeforces Round 498 (Div. 3) {1006} | PROGRAMMING | 60672 | 2400 | |
| 1063 | Pave the Parallelepiped | bitmasks brute force combinatorics math number theory | Statement | B | Codeforces Round 497 (Div. 1) {1007} | PROGRAMMING | Editorial for Codeforces Round #497 by Skyglow | 2400 | |
| 4087 | The Wu | bitmasks brute force data structures | Statement | D | Codeforces Round 502 (in memory of Leopoldo Taravilse, Div. 1 + Div. 2) {1017} | PROGRAMMING | Разбор (англ.) | 1900 | |
| 512 | Boolean Computer | bitmasks brute force fft math | Statement | F | Lyft Level 5 Challenge 2018 - Elimination Round {1033} | PROGRAMMING | The Lyft Level 5 Challenge 2018 Elimination Round (Div. 1 + Div. 2) Editorial | 2800 | |
| 472 | Sources and Sinks | bitmasks brute force dfs and similar | Statement | G | Educational Codeforces Round 50 (Rated for Div. 2) {1036} | PROGRAMMING | 61727 | 2800 | |
| 1154 | Maximum Matching | bitmasks brute force dfs and similar dp graphs | Statement | E | Codeforces Round 508 (Div. 2) {1038} | PROGRAMMING | Tutorial | 2400 | |
| 19607 | Vitamins | bitmasks brute force dp implementation | Statement | B | Codeforces Round 510 (Div. 2) {1042} | PROGRAMMING | Tutorial | 1200 | |
| 37176 | Petr and a Combination Lock | bitmasks brute force dp | Statement | B | Hello 2019 {1097} | PROGRAMMING | 64310 | 1200 | |
| 267 | Mateusz and an Infinite Sequence | bitmasks brute force dp strings | Statement | H | Hello 2019 {1097} | PROGRAMMING | 64310 | 3000 | |
| 2434 | Elongated Matrix | binary search bitmasks brute force dp graphs | Statement | F | Codeforces Round 531 (Div. 3) {1102} | PROGRAMMING | 64439 | 2400 | |
| 2061 | Helping Hiasat | bitmasks brute force dp meet-in-the-middle | Statement | E | Codeforces Round 533 (Div. 2) {1105} | PROGRAMMING | Tutorial | 2200 | |
| 837 | Mystery Circuit | bitmasks brute force | Statement | C | April Fools Day Contest 2019 {1145} | PROGRAMMING | 66327 | ||
| 13130 | Dima and a Bad XOR | bitmasks brute force constructive algorithms dp | Statement | B | Codeforces Round 553 (Div. 2) {1151} | PROGRAMMING | Codeforces Round #553 (Div. 2) Editorial | 1600 | |
| 1051 | Magical Permutation | bitmasks brute force constructive algorithms data structures graphs math | Statement | E | Codeforces Round 558 (Div. 2) {1163} | PROGRAMMING | 66943 | 2800 | |
| 3038 | The LCMs Must be Large | bitmasks brute force constructive algorithms math number theory | Statement | E | Codeforces Round 561 (Div. 2) {1166} | PROGRAMMING | Codeforces Round #561 (Div. 2) Editorial | 2000 | |
| 2293 | Two Pizzas | bitmasks brute force | Statement | F | Codeforces Round 568 (Div. 2) {1185} | PROGRAMMING | Editorial for Codeforces Round #568 (Div. 2) | 2200 | |
| 2102 | Count The Rectangles | bitmasks brute force data structures geometry sortings | Statement | E | Educational Codeforces Round 68 (Rated for Div. 2) {1194} | PROGRAMMING | Разбор Educational Codeforces Round 68 | 2200 | |
| 7621 | Shortest Cycle | bitmasks brute force graphs shortest paths | Statement | B | Codeforces Round 580 (Div. 1) {1205} | PROGRAMMING | 69158 | 1900 | |
| 3299 | Rotate Columns (easy version) | bitmasks brute force dp greedy sortings | Statement | E1 | Codeforces Round 584 - Dasha Code Championship - Elimination Round (rated, open for everyone, Div. 1 + Div. 2) {1209} | PROGRAMMING | 69791 | 2000 | |
| 7903 | The Number Of Good Substrings | binary search bitmasks brute force | Statement | C | Educational Codeforces Round 72 (Rated for Div. 2) {1217} | PROGRAMMING | Educational Codeforces Round 72 Editorial | 1600 | |
| 1024 | Graph And Numbers | bitmasks brute force combinatorics dp meet-in-the-middle | Statement | G | Educational Codeforces Round 73 (Rated for Div. 2) {1221} | PROGRAMMING | Разбор Educational Codeforces Round 73 | 2900 | |
| 9882 | p-binary | bitmasks brute force math | Statement | C | Technocup 2020 - Elimination Round 2 {1225} | PROGRAMMING | 70898 | 1600 | |
| 2313 | Daniel and Spring Cleaning | bitmasks brute force combinatorics dp | Statement | F | Codeforces Round 597 (Div. 2) {1245} | PROGRAMMING | Codeforces Round #597 (Div. 2) Editorial | 2300 | |
| 2415 | Make Them Similar | bitmasks brute force hashing meet-in-the-middle | Statement | F | Educational Codeforces Round 76 (Rated for Div. 2) {1257} | PROGRAMMING | Educational Codeforces Round 76 Editorial | 2400 | |
| 8768 | Dr. Evil Underscores | bitmasks brute force dfs and similar divide and conquer dp greedy strings trees | Statement | D | Codeforces Round 613 (Div. 2) {1285} | PROGRAMMING | Codeforces Round #613 (Div. 2) Editorial | 1800 | |
| 79 | Keep talking and nobody explodes -- easy | bitmasks brute force expression parsing | Statement | F | AIM Tech Poorly Prepared Contest (unrated, funny, Div. 1 preferred) {1302} | PROGRAMMING | 73599 | ||
| 1085 | Wise Men (Easy Version) | bitmasks brute force dp meet-in-the-middle | Statement | F1 | Codeforces Global Round 7 {1326} | PROGRAMMING | 2000.0 | 74961 | 2600 |
| 904 | Chiori and Doll Picking (easy version) | bitmasks brute force combinatorics math | Statement | E1 | Codeforces Round 635 (Div. 1) {1336} | PROGRAMMING | 1750.0 | Codeforces Round #635 Editorial | 2600 |
| 720 | Chiori and Doll Picking (hard version) | bitmasks brute force combinatorics math | Statement | E2 | Codeforces Round 635 (Div. 1) {1336} | PROGRAMMING | 1500.0 | Codeforces Round #635 Editorial | 3400 |
| 3493 | Perfect Triples | bitmasks brute force constructive algorithms divide and conquer greedy implementation math | Statement | C | Codeforces Round 633 (Div. 1) {1338} | PROGRAMMING | 1500.0 | Editorial | |
| 1160 | Make It Ascending | bitmasks brute force dp | Statement | F | Educational Codeforces Round 86 (Rated for Div. 2) {1342} | PROGRAMMING | 76633 | 2900 | |
| 13690 | Spy-string | bitmasks brute force constructive algorithms dp hashing strings | Statement | F | Codeforces Round 644 (Div. 3) {1360} | PROGRAMMING | Codeforces Round #644 (Div. 3) Editorial | 1700 | |
| 4923 | Binary Median | bitmasks brute force constructive algorithms | Statement | H | Codeforces Round 644 (Div. 3) {1360} | PROGRAMMING | Codeforces Round #644 (Div. 3) Editorial | 2100 | |
| 21342 | Johnny and His Hobbies | bitmasks brute force | Statement | B | Codeforces Round 647 (Div. 2) - Thanks, Algo Muse! {1362} | PROGRAMMING | 1000.0 | Codeforces Round #647 Editorial | 1200 |
| 22355 | a-Good String | bitmasks brute force divide and conquer dp implementation | Statement | D | Codeforces Round 656 (Div. 3) {1385} | PROGRAMMING | Codeforces Round #656 (Div. 3) Editorial | 1500 | |
| 5832 | 505 | bitmasks brute force dp implementation | Statement | D | Codeforces Round 663 (Div. 2) {1391} | PROGRAMMING | 2000.0 | Codeforces Round #663 (Div. 2) Editorial | |
| 15404 | Boboniu and Bit Operations | bitmasks brute force dp | Statement | C | Codeforces Round 664 (Div. 2) {1395} | PROGRAMMING | 1000.0 | Codeforces Round #664 Editorial | 1600 |
| 6263 | XOR-gun | bitmasks brute force constructive algorithms | Statement | D | Technocup 2021 - Elimination Round 2 {1415} | PROGRAMMING | 2000.0 | Editorial of Codeforces Round 687 (Technocup 2021 — Elimitation Round 2) | |
| 2244 | A Bit Similar | bitmasks brute force hashing string suffix structures strings two pointers | Statement | E | Educational Codeforces Round 101 (Rated for Div. 2) {1469} | PROGRAMMING | Educational Codeforces Round 101 Editorial | ||
| 6825 | Strange Definition | bitmasks brute force data structures graphs math number theory | Statement | B | Codeforces Round 694 (Div. 1) {1470} | PROGRAMMING | 750.0 | 86464 | |
| 15457 | Berland Crossword | binary search bitmasks brute force greedy implementation | Statement | B | Educational Codeforces Round 105 (Rated for Div. 2) {1494} | PROGRAMMING | Educational Codeforces Round 105 Editorial | ||
| 23009 | ABC String | bitmasks brute force implementation | Statement | A | Educational Codeforces Round 105 (Rated for Div. 2) {1494} | PROGRAMMING | Educational Codeforces Round 105 Editorial | ||
| 989 | Chips on a Board | bitmasks brute force data structures games sortings | Statement | G | Educational Codeforces Round 107 (Rated for Div. 2) {1511} | PROGRAMMING | 89634 | ||
| 26685 | AGAGA XOOORRR | bitmasks brute force dp greedy | Statement | B | Codeforces Round 717 (Div. 2) {1516} | PROGRAMMING | 1000.0 | Codeforces round #717 editorial | |
| 2540 | Love-Hate | bitmasks brute force dp probabilities | Statement | D | Deltix Round, Spring 2021 (open for everyone, rated, Div. 1 + Div. 2) {1523} | PROGRAMMING | 2250.0 | Deltix Round, Spring 2021. Editorial | 2400 |
| 691 | A Serious Referee | bitmasks brute force dfs and similar sortings | Statement | G | Codeforces Global Round 15 {1552} | PROGRAMMING | 2500.0 | Editorial of Global Round 15 | |
| 13947 | Cobb | bitmasks brute force greedy math | Statement | B | Codeforces Round 735 (Div. 2) {1554} | PROGRAMMING | 1250.0 | Editorial of Codeforces Round #735 (Div. 2) | 1700 |
| 6831 | Nearest Beautiful Number (easy version) | binary search bitmasks brute force constructive algorithms dfs and similar greedy | Statement | F1 | Codeforces Round 739 (Div. 3) {1560} | PROGRAMMING | 94009 | 1900 | |
| 5092 | Nearest Beautiful Number (hard version) | bitmasks brute force constructive algorithms dfs and similar dp greedy | Statement | F2 | Codeforces Round 739 (Div. 3) {1560} | PROGRAMMING | 94009 | 2100 | |
| 903 | Playoff Restoration | bitmasks brute force hashing implementation meet-in-the-middle | Statement | E | Educational Codeforces Round 113 (Rated for Div. 2) {1569} | PROGRAMMING | 94721 | ||
| 352 | Bob's Beautiful Array | bitmasks brute force greedy | Statement | J | Bubble Cup 14 - Finals Online Mirror (Unrated, ICPC Rules, Teams Preferred, Div. 1) {1599} | PROGRAMMING | BubbleCup2021.pdf | ||
| 7332 | BA-String | bitmasks brute force dp greedy implementation math shortest paths | Statement | C | Educational Codeforces Round 119 (Rated for Div. 2) {1620} | PROGRAMMING | 98061 | ||
| 2278 | Math Test | bitmasks brute force greedy | Statement | E | Educational Codeforces Round 120 (Rated for Div. 2) {1622} | PROGRAMMING | Educational Codeforces Round 120 Editorial | ||
| 14224 | Strange Test | binary search bitmasks brute force greedy math | Statement | C | Codeforces Round 769 (Div. 2) {1632} | PROGRAMMING | 1500.0 | Editorial of Codeforces Round #769 | |
| 1554 | Two Arrays | bitmasks brute force combinatorics hashing probabilities two pointers | Statement | D | Codeforces Round 773 (Div. 1) {1641} | PROGRAMMING | 1750.0 | Codeforces Round #773 editorial | |
| 20575 | Factorials and Powers of Two | bitmasks brute force constructive algorithms math | Statement | C | Codeforces Round 774 (Div. 2) {1646} | PROGRAMMING | 1250.0 | Codeforces Round #774 (Div. 2) Editorial | 1500 |
| 3219 | 388535 (Hard Version) | bitmasks brute force data structures math | Statement | D2 | Codeforces Round 779 (Div. 2) {1658} | PROGRAMMING | 750.0 | Codeforces Round #779 (Div. 2) Editorial | |
| 2027 | AND-MEX Walk | bitmasks brute force data structures dfs and similar dsu graphs greedy | Statement | E | Codeforces Round 782 (Div. 2) {1659} | PROGRAMMING | 2250.0 | Codeforces Round #782 (Div. 2) Editorial | |
| 1457 | Typical Party in Dorm | bitmasks brute force combinatorics dp strings two pointers | Statement | E | Codeforces Round 791 (Div. 2) {1679} | PROGRAMMING | 2250.0 | Codeforces Round #791 (Div. 2) Editorial | |
| 23775 | Cirno's Perfect Bitmasks Classroom | bitmasks brute force constructive algorithms | Statement | A | Codeforces Round 796 (Div. 2) {1688} | PROGRAMMING | 500.0 | Tutorial | |
| 1411 | ANDfinity | bitmasks brute force constructive algorithms dfs and similar dsu graphs | Statement | E | Codeforces Round 798 (Div. 2) {1689} | PROGRAMMING | 2500.0 | Editorial for Codeforces Round #798 (Div. 2) | |
| 1169 | Tree Recovery | bitmasks brute force constructive algorithms dfs and similar dsu graphs trees | Statement | F | Codeforces Global Round 21 {1696} | PROGRAMMING | 2500.0 | Editorial of Codeforces Global Round 21 | |
| 33330 | XOR Mixup | bitmasks brute force | Statement | A | Codeforces Round 803 (Div. 2) {1698} | PROGRAMMING | 250.0 | Codeforces Round #803 (Div. 2) Editorial | |
| 13004 | Good Key, Bad Key | bitmasks brute force dp greedy math | Statement | G | Codeforces Round 806 (Div. 4) {1703} | PROGRAMMING | 104786 | ||
| 33744 | Minimum Varied Number | bitmasks brute force greedy | Statement | C | Codeforces Round 811 (Div. 3) {1714} | PROGRAMMING | Codeforces Round #811 (Div. 3) Editorial | ||
| 6795 | Xor-Subsequence (easy version) | bitmasks brute force dp strings trees | Statement | D1 | Codeforces Round 815 (Div. 2) {1720} | PROGRAMMING | 1500.0 | Codeforces Round #815 (Div. 2) Editorial | |
| 2662 | Prefix Function Queries | bitmasks brute force data structures hashing string suffix structures strings trees | Statement | E | Educational Codeforces Round 134 (Rated for Div. 2) {1721} | PROGRAMMING | 106416 | ||
| 7806 | Maximum AND | bitmasks brute force divide and conquer greedy math sortings | Statement | D | Educational Codeforces Round 134 (Rated for Div. 2) {1721} | PROGRAMMING | 106416 | ||
| 12551 | Even Subarrays | bitmasks brute force hashing math number theory | Statement | C | Codeforces Round 841 (Div. 2) and Divide by Zero 2022 {1731} | PROGRAMMING | 1500.0 | Codeforces Round #841 (Div. 2) and Divide By Zero 2022 Editorial | |
| 3158 | Sheikh (Hard Version) | binary search bitmasks brute force greedy implementation two pointers | Statement | C2 | Codeforces Round 830 (Div. 2) {1732} | PROGRAMMING | 1000.0 | 108327 | 2100 |
| 1987 | Kirill and Company | bitmasks brute force dp graphs shortest paths | Statement | G | Codeforces Round 826 (Div. 3) {1741} | PROGRAMMING | 107908 | ||
| 13684 | Orray | bitmasks brute force greedy math | Statement | G | Codeforces Round 827 (Div. 4) {1742} | PROGRAMMING | 107962 | ||
| 10855 | SlavicG's Favorite Problem | bitmasks brute force constructive algorithms data structures dfs and similar graphs greedy | Statement | G | Codeforces Round 835 (Div. 4) {1760} | PROGRAMMING | 109348 | ||
| 2887 | Carry Bit | bitmasks brute force combinatorics dp math | Statement | D | Pinely Round 1 (Div. 1 + Div. 2) {1761} | PROGRAMMING | 1750.0 | Pinely Round 1 (Div. 1 + Div. 2) Editorial | |
| 1325 | Algebra Flash | bitmasks brute force dp graphs meet-in-the-middle trees | Statement | E | Educational Codeforces Round 140 (Rated for Div. 2) {1767} | PROGRAMMING | 110225 | ||
| 11648 | Flexible String | bitmasks brute force strings | Statement | C | Codeforces Round 848 (Div. 2) {1778} | PROGRAMMING | 1250.0 | Codeforces Round #848 (Div. 2) Editorial | |
| 1981 | Three Chairs | bitmasks brute force combinatorics data structures number theory sortings | Statement | F | Codeforces Round 846 (Div. 2) {1780} | PROGRAMMING | 2000.0 | 111841 | |
| 1968 | Serval and Shift-Shift-Shift | bitmasks brute force constructive algorithms implementation | Statement | D | Codeforces Round 853 (Div. 2) {1789} | PROGRAMMING | 1750.0 | Codeforces Round #853 (Div. 2) Editorial | |
| 45515 | We Need the Zero | bitmasks brute force | Statement | A | Codeforces Round 862 (Div. 2) {1805} | PROGRAMMING | 500.0 | Editorial of Codeforces Round #862 (Div. 2) | |
| 2009 | Walk the Runway | bitmasks brute force data structures dp graphs implementation sortings | Statement | E | Codeforces Round 870 (Div. 2) {1826} | PROGRAMMING | 2500.0 | Codeforces Round #870 (Div. 2) Editorial | 2400 |
| 15007 | Vampiric Powers, anyone? | bitmasks brute force data structures dp greedy | Statement | C | Codeforces Round 882 (Div. 2) {1847} | PROGRAMMING | 1500.0 | Tutorial | |
| 4412 | Earn or Unlock | bitmasks brute force dp | Statement | B | Codeforces Round 889 (Div. 1) {1854} | PROGRAMMING | 1500.0 | Editorial of Codeforces Round 889 (Div. 1 + Div. 2) | |
| 7760 | Magic Will Save the World | binary search bitmasks brute force dp | Statement | F | Codeforces Round 894 (Div. 3) {1862} | PROGRAMMING | Tutorial | ||
| 17583 | Sets and Union | bitmasks brute force constructive algorithms greedy | Statement | B | Codeforces Round 899 (Div. 2) {1882} | PROGRAMMING | 1000.0 | Codeforces Round 899 (Div. 2) Editorial | |
| 7438 | Maximum And Queries (easy version) | binary search bitmasks brute force greedy | Statement | D1 | Codeforces Round 912 (Div. 2) {1903} | PROGRAMMING | 1500.0 | Codeforces Round #912 (Div. 2) Editorial | |
| 15062 | StORage room | bitmasks brute force constructive algorithms greedy | Statement | B | Codeforces Round 912 (Div. 2) {1903} | PROGRAMMING | 1000.0 | Codeforces Round #912 (Div. 2) Editorial | |
| 2145 | Vlad and Avoiding X | bitmasks brute force constructive algorithms dfs and similar dp implementation | Statement | F | Codeforces Round 928 (Div. 4) {1926} | PROGRAMMING | 126132 | ||
| 2147 | Sasha and the Happy Tree Cutting | bitmasks brute force dp fft graphs greedy trees | Statement | E | Codeforces Round 926 (Div. 2) {1929} | PROGRAMMING | 2500.0 | Codeforces Round #926 (Div. 2) Editorial. | |
| 981 | Maximize the Difference | bitmasks brute force dfs and similar | Statement | F | think-cell Round 1 {1930} | PROGRAMMING | 2750.0 | think-cell Round 1 Editorial | |
| 1217 | Turtle Magic: Royal Turtle Shell Pattern | bitmasks brute force combinatorics math | Statement | G | Codeforces Round 929 (Div. 3) {1933} | PROGRAMMING | Codeforces Round 929 (Div. 3) Editorial | ||
| 971 | GCD is Greater | bitmasks brute force number theory | Statement | H | Codeforces Round 935 (Div. 3) {1945} | PROGRAMMING | 127377 | ||
| 5688 | Birthday Gift | bitmasks brute force constructive algorithms greedy implementation | Statement | D | Codeforces Round 936 (Div. 2) {1946} | PROGRAMMING | 1750.0 | Codeforces Round #936 (Div. 2) Editorial | |
| 1005 | MST with Matching | bitmasks brute force trees | Statement | G | Educational Codeforces Round 163 (Rated for Div. 2) {1948} | PROGRAMMING | Educational Codeforces Round 163 Editorial | ||
| 1558 | The Most Reckless Defense | bitmasks brute force constructive algorithms dp flows graph matchings | Statement | H | Codeforces Round 938 (Div. 3) {1955} | PROGRAMMING | 128243 | ||
| 4867 | Nene and the Mex Operator | bitmasks brute force constructive algorithms divide and conquer dp greedy implementation | Statement | D | Codeforces Round 939 (Div. 2) {1956} | PROGRAMMING | 1750.0 | [Editorial] Codeforces Round 939 (Div. 2) | |
| 5991 | A BIT of an Inequality | bitmasks brute force dp math | Statement | D | Codeforces Round 940 (Div. 2) and CodeCraft-23 {1957} | PROGRAMMING | 1750.0 | Codeforces Round #940 and CodeCraft-23 (Div. 2) Editorial | 1900 |
| 2307 | Fenwick Tree | bitmasks brute force combinatorics data structures dp math trees | Statement | C | Codeforces Round 942 (Div. 1) {1967} | PROGRAMMING | 1250.0 | Tutorial | 2300 |
| 357 | Maximum GCD Sum Queries | bitmasks brute force dp implementation number theory | Statement | F | Codeforces Round 945 (Div. 2) {1973} | PROGRAMMING | 3000.0 | Editorial for Codeforces Round #945 (Div. 2) | 3100 |
| 1083 | Set | bitmasks brute force combinatorics dfs and similar divide and conquer dp math | Statement | F | Codeforces Round 947 (Div. 1 + Div. 2) {1975} | PROGRAMMING | 2500.0 | editorial_zh.pdf | 2600 |
| 2432 | XORificator | bitmasks brute force greedy hashing | Statement | D | Codeforces Round 948 (Div. 2) {1977} | PROGRAMMING | 2000.0 | 129858 | 2300 |
| 7966 | Fixing a Binary String | bitmasks brute force constructive algorithms greedy hashing strings | Statement | D | Codeforces Round 951 (Div. 2) {1979} | PROGRAMMING | 2000.0 | Codeforces Round 951 (Div. 2) Editorial | |
| 361 | Your Loss | bitmasks brute force trees | Statement | G | Codeforces Round 956 (Div. 2) and ByteRace 2024 {1983} | PROGRAMMING | 3000.0 | ||
| 23628 | Substring and Subsequence | bitmasks brute force dp graphs greedy hashing strings trees | Statement | B | Educational Codeforces Round 167 (Rated for Div. 2) {1989} | PROGRAMMING | Educational Codeforces Round 167 Editorial | ||
| 1689 | Minecraft | bitmasks brute force dp math | Statement | G | Codeforces Round 959 sponsored by NEAR (Div. 1 + Div. 2) {1994} | PROGRAMMING | 2750.0 | Video Tutorial | |
| 3044 | Cases | bitmasks brute force combinatorics dfs and similar dp graphs greedy strings | Statement | D | Codeforces Round 961 (Div. 2) {1995} | PROGRAMMING | 2250.0 | Video Tutorial | |
| 4096 | Expected Power | bitmasks brute force dp math number theory probabilities | Statement | E | Codeforces Round 976 (Div. 2) and Divide By Zero 9.0 {2020} | PROGRAMMING | 2000.0 | Tutorial for Codeforces Round 976 (Div. 2) and Divide By Zero 9.0 | |
| 271 | Bit Game (Easy Version) | bitmasks brute force games math | Statement | E1 | Codeforces Round 982 (Div. 2) {2027} | PROGRAMMING | 2000.0 | Codeforces Round #982 (Div. 2) Editorial | |
| 13839 | Shohag Loves XOR (Easy Version) | bitmasks brute force math number theory | Statement | C1 | CodeTON Round 9 (Div. 1 + Div. 2, Rated, Prizes!) {2039} | PROGRAMMING | 1000.0 | Editorial of CodeTON Round 9 (Div. 1 + Div. 2) | |
| 5068 | Shohag Loves XOR (Hard Version) | bitmasks brute force math number theory | Statement | C2 | CodeTON Round 9 (Div. 1 + Div. 2, Rated, Prizes!) {2039} | PROGRAMMING | 1500.0 | Editorial of CodeTON Round 9 (Div. 1 + Div. 2) | |
| 1867 | Matrix Transformation | bitmasks brute force dfs and similar graphs implementation | Statement | E | Educational Codeforces Round 173 (Rated for Div. 2) {2043} | PROGRAMMING | Educational Codeforces Round 173 Editorial | ||
| 15452 | Kevin and Binary Strings | bitmasks brute force greedy strings | Statement | C | Codeforces Global Round 28 {2048} | PROGRAMMING | 1000.0 | Tutorial | |
| 4073 | Kevin and And | bitmasks brute force dp greedy | Statement | E | IAEPC Preliminary Contest (Codeforces Round 999, Div. 1 + Div. 2) {2061} | PROGRAMMING | 2000.0 | IAEPC Preliminary Contest (Codeforces Round 999, Div. 1 + Div. 2) Editorial | |
| 22378 | XOR and Triangle | binary search bitmasks brute force greedy | Statement | C | Codeforces Round 1009 (Div. 3) {2074} | PROGRAMMING | Codeforces Round 1009 (Div. 3) — Editorial | ||
| 6006 | Equalization | bitmasks brute force dp greedy math | Statement | D | Educational Codeforces Round 176 (Rated for Div. 2) {2075} | PROGRAMMING | Educational Codeforces Round 176 Editorial | ||
| 1698 | Zebra-like Numbers | bitmasks brute force dfs and similar dp math | Statement | E | Educational Codeforces Round 177 (Rated for Div. 2) {2086} | PROGRAMMING | Educational Codeforces Round 177 Editorial | ||
| 6031 | Hackers and Neural Networks | bitmasks brute force greedy | Statement | F | Codeforces Round 1016 (Div. 3) {2093} | PROGRAMMING | Codeforces Round 1016 (Div. 3) Editorial | ||
| 5627 | Small Operations | binary search bitmasks brute force dfs and similar dp math number theory sortings | Statement | F | Codeforces Round 1027 (Div. 3) {2114} | PROGRAMMING | 143268 | ||
| 3895 | Wafu! | bitmasks brute force dp math | Statement | G | Codeforces Round 1042 (Div. 3) {2131} | PROGRAMMING | Codeforces Round 1042 (Div. 3) Editorial | ||
| 3583 | Maple and Tree Beauty (Hard Version) | bitmasks brute force dfs and similar divide and conquer dp fft trees | Statement | C2 | Codeforces Round 1048 (Div. 1) {2138} | PROGRAMMING | 750.0 | Codeforces Round 1048 (Div. 1, Div. 2) Editorial | |
| 2283 | Maximum OR Popcount | binary search bitmasks brute force data structures greedy | Statement | E | Codeforces Global Round 29 (Div. 1 + Div. 2) {2147} | PROGRAMMING | 2500.0 | ||
| 3822 | Taiga's Carry Chains | bitmasks brute force dp greedy | Statement | D | Codeforces Round 1068 (Div. 2) {2173} | PROGRAMMING | 1750.0 | ||
| 709 | Cool Problem | bitmasks brute force divide and conquer dp math | Statement | D | Codeforces Round 1077 (Div. 1) {2187} | PROGRAMMING | 2000.0 | Codeforces Round 1077 (Div. 1, Div. 2) Editorial | |
| 14726 | XOR Convenience (Easy Version) | bitmasks brute force constructive algorithms math | Statement | C1 | Codeforces Round 1075 (Div. 2) {2189} | PROGRAMMING | 1250.0 | Codeforces Round 1075 (Div. 2) Editorial | |
| 6517 | XOR-convenience (Hard Version) | bitmasks brute force constructive algorithms math | Statement | C2 | Codeforces Round 1075 (Div. 2) {2189} | PROGRAMMING | 750.0 | Codeforces Round 1075 (Div. 2) Editorial | |
| 311 | Fuzzy Concatenation (Easy Version) | binary search bitmasks brute force data structures greedy string suffix structures | Statement | E1 | Codeforces Round 1079 (Div. 1) {2196} | PROGRAMMING | 2000.0 | Tutorial | |
| 234 | Simons and Diophantus Equation | bitmasks brute force data structures number theory | Statement | G | Codeforces Round 1083 (Div. 2) {2205} | PROGRAMMING | 3250.0 | Tutorial | |
| 165 | EXPloration, EXPloitation, and Gain Some EXPerience! | bitmasks brute force dp greedy implementation | Statement | D | Codeforces Round 1092 (Unrated, Div. 1, Based on THUPC 2026 — Finals) {2215} | PROGRAMMING | 2750.0 | 152930 | |
| 17265 | The 67th XOR Problem | binary search bitmasks brute force trees | Statement | E | Codeforces Round 1090 (Div. 4) {2218} | PROGRAMMING | Codeforces Round 1090 (Div. 4) Editorial | ||
| 8335 | Exceptional Segments | bitmasks brute force math | Statement | D | Educational Codeforces Round 189 (Rated for Div. 2) {2225} | PROGRAMMING | Tutorial | ||
| 1419 | Product of Closures | bitmasks brute force constructive algorithms dp greedy implementation math | Statement | E | Educational Codeforces Round 192 (Rated for Div. 2) {2242} | PROGRAMMING | 155047 | ||
| 2875 | diss_quack and Array Game | bitmasks brute force games greedy | Statement | D | Codeforces Round 1108 (Div. 2) {2246} | PROGRAMMING | 1750.0 | Codeforces Round 1108 (Div. 2) Editorial |