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Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 18877 | Longest Regular Bracket Sequence | constructive algorithms data structures dp greedy sortings strings | Statement | C | Codeforces Beta Round 5 {5} | PROGRAMMING | C, D и E с CBR5 - разбор | 1900 | |
| 970 | Tricky and Clever Password | binary search constructive algorithms data structures greedy hashing strings | Statement | E | Codeforces Beta Round 30 (Codeforces format) {30} | PROGRAMMING | Codeforces Beta Round #30. Tutorial for problem A | 2700 | |
| 2264 | Old Berland Language | data structures greedy trees | Statement | C | Codeforces Beta Round 37 {37} | PROGRAMMING | Codeforces Beta Round #37 (Tutorial) | 1900 | |
| 2149 | Beaver | data structures dp greedy hashing strings two pointers | Statement | C | Codeforces Beta Round 71 {79} | PROGRAMMING | Codeforces Beta Round #71 Editorial | 1800 | |
| 3347 | Petr# | brute force data structures hashing strings | Statement | B | Codeforces Beta Round 86 (Div. 1 Only) {113} | PROGRAMMING | Codeforces Beta Round #86 Editorial | 1900 | |
| 1406 | Last Chance | data structures implementation strings | Statement | E | Codeforces Beta Round 98 (Div. 2) {137} | PROGRAMMING | Codeforces Beta Round #98 (Div. 2): Editorial | 2000 | |
| 3230 | String Manipulation 1.0 | *special binary search brute force data structures strings | Statement | C | VK Cup 2012 Qualification Round 2 {159} | PROGRAMMING | Simple solution to vk cup Qualification Round 1 and 2 | 2000 | |
| 2322 | e-Government | data structures dfs and similar dp strings trees | Statement | E | VK Cup 2012 Round 2 {163} | PROGRAMMING | VK Cup 2012 Round 2 — Разбор | 2800 | |
| 651 | The Next Good String | data structures greedy hashing strings | Statement | D | Codeforces Round 124 (Div. 1) {196} | PROGRAMMING | Codeforces Round #124 — editorial | 2600 | |
| 1710 | Little Elephant and Strings | data structures implementation string suffix structures two pointers | Statement | E | Codeforces Round 129 (Div. 1) {204} | PROGRAMMING | Tutorial | 2800 | |
| 1036 | Two Permutations | data structures hashing strings | Statement | E | Codeforces Round 131 (Div. 1) {213} | PROGRAMMING | Codeforces Round #131 Tutorial | 2600 | |
| 2043 | Two Strings | data structures dp strings | Statement | B | Codeforces Round 138 (Div. 1) {223} | PROGRAMMING | 2000 | ||
| 2558 | Cyclical Quest | data structures string suffix structures strings | Statement | C | Codeforces Round 146 (Div. 1) {235} | PROGRAMMING | Codeforces Round #146 Tutorial | 2700 | |
| 14634 | Good Substrings | data structures strings | Statement | D | Codeforces Round 166 (Div. 2) {271} | PROGRAMMING | editroal | 1800 | |
| 427 | Mirror Room | data structures implementation | Statement | E | Codeforces Round 168 (Div. 1) {274} | PROGRAMMING | Codeforces Round #168 Editorial | 3000 | |
| 1053 | Students' Revenge | data structures greedy sortings | Statement | C | Codeforces Round 193 (Div. 2) {332} | PROGRAMMING | 8447 | 2200 | |
| 1232 | Three strings | data structures dsu string suffix structures strings | Statement | E | MemSQL Start[c]UP 2.0 - Round 1 {452} | PROGRAMMING | MemSQL Start[c]UP 2.0 Round 1 and 2 Editorials | 2400 | |
| 507 | Design Tutorial: Increase the Constraints | bitmasks data structures fft | Statement | G | Codeforces Round 270 {472} | PROGRAMMING | Editorial | 2800 | |
| 19781 | Misha and Changing Handles | data structures dsu strings | Statement | B | Codeforces Round 285 (Div. 2) {501} | PROGRAMMING | Tutorial | 1100 | |
| 8433 | Watto and Mechanism | binary search data structures hashing string suffix structures strings | Statement | C | Codeforces Round 291 (Div. 2) {514} | PROGRAMMING | Codeforces Round #291 (Div. 2) Editorial | 1900 | |
| 6937 | A and B and Interesting Substrings | data structures dp two pointers | Statement | D | Codeforces Round 294 (Div. 2) {519} | PROGRAMMING | Editorial | 1900 | |
| 645 | And Yet Another Bracket Sequence | data structures greedy hashing string suffix structures strings | Statement | F | VK Cup 2015 - Round 1 {524} | PROGRAMMING | VK Cup Round 1 (+ online mirror) editorial | 2700 | |
| 570 | Tavas on the Path | data structures divide and conquer trees | Statement | E | Codeforces Round 299 (Div. 1) {536} | PROGRAMMING | Codeforces Round #299 Editorial | 3100 | |
| 2778 | Mike and Friends | data structures string suffix structures strings trees | Statement | E | Codeforces Round 305 (Div. 1) {547} | PROGRAMMING | Codeforces Round #305 Editorial | 2800 | |
| 1253 | Ann and Half-Palindrome | data structures dp graphs string suffix structures strings trees | Statement | E | Codeforces Round 311 (Div. 2) {557} | PROGRAMMING | Codeforces Round #311 (Div.2) Editorial | 2700 | |
| 7717 | A Simple Task | data structures sortings strings | Statement | E | Codeforces Round 312 (Div. 2) {558} | PROGRAMMING | Codeforces Round #312 (Div. 2) Editorial | 2600 | |
| 2707 | Kefa and Watch | data structures hashing strings | Statement | E | Codeforces Round 321 (Div. 2) {580} | PROGRAMMING | Codeforces Round #321 Editorial | 2700 | |
| 1519 | Duff is Mad | data structures strings | Statement | F | Codeforces Round 326 (Div. 1) {587} | PROGRAMMING | Codeforces Round #326 (Editorial) | 3000 | |
| 1281 | Acyclic Organic Compounds | data structures dfs and similar dsu hashing strings trees | Statement | D | Codeforces Round 333 (Div. 1) {601} | PROGRAMMING | Codeforces Round #333 — editorial | 2400 | |
| 1097 | Alphabet Permutations | data structures strings | Statement | E | Codeforces Round 337 (Div. 2) {610} | PROGRAMMING | Codeforces Round #337 (Div.2) Editorial | 2700 | |
| 10154 | Replace To Make Regular Bracket Sequence | data structures expression parsing math | Statement | C | Educational Codeforces Round 4 {612} | PROGRAMMING | 22299 | 1500 | |
| 2492 | Messenger | data structures hashing implementation string suffix structures strings | Statement | D | Codeforces Round 344 (Div. 2) {631} | PROGRAMMING | Editorial Codeforces Round #344 (Div. 2) | 2100 | |
| 3453 | Spy Syndrome 2 | data structures dp hashing implementation sortings string suffix structures strings | Statement | C | Manthan, Codefest 16 {633} | PROGRAMMING | Manthan, Codefest 16: Editorials | 1900 | |
| 1024 | Hostname Aliases | *special binary search data structures implementation sortings strings | Statement | C | CROC 2016 - Qualification {644} | PROGRAMMING | 2300 | ||
| 1248 | Paper task | data structures string suffix structures strings | Statement | F | IndiaHacks 2016 - Online Edition (Div. 1 + Div. 2) {653} | PROGRAMMING | IndiaHacks Finals 2016 — Editorial | 2500 | |
| 1741 | Forensic Examination | data structures string suffix structures | Statement | E | Codeforces Round 349 (Div. 1) {666} | PROGRAMMING | Codeforces Round #349 Editorial | 3100 | |
| 3489 | Correct Bracket Sequence Editor | data structures dsu strings | Statement | E | Codeforces Round 350 (Div. 2) {670} | PROGRAMMING | Codeforces Round #350 (Div.2) Editorial | 1700 | |
| 1691 | Legen... | data structures dp matrices strings | Statement | D | Codeforces Round 362 (Div. 1) {696} | PROGRAMMING | Codeforces Round #362 (Editorial) | 2700 | |
| 603 | Huffman Coding on Segment | data structures greedy | Statement | D | Codeforces Round 364 (Div. 1) {700} | PROGRAMMING | 46283 | 3000 | |
| 2637 | String Set Queries | brute force data structures hashing string suffix structures strings | Statement | F | Educational Codeforces Round 16 {710} | PROGRAMMING | Editorial of Educational Codeforces Round 16 | 2700 | |
| 3377 | Generating Sets | binary search data structures dfs and similar greedy strings trees | Statement | D | Intel Code Challenge Elimination Round (Div. 1 + Div. 2, combined) {722} | PROGRAMMING | Tutorial | 1900 | |
| 2492 | Dense Subsequence | data structures greedy strings | Statement | D | Intel Code Challenge Final Round (Div. 1 + Div. 2, Combined) {724} | PROGRAMMING | Tutorial | 1900 | |
| 1647 | Games on a CD | data structures hashing string suffix structures strings | Statement | E | Technocup 2017 - Elimination Round 1 (Unofficially Open for Everyone, Rated for Div. 2) {727} | PROGRAMMING | Tutorial | 2300 | |
| 243 | Arpa’s abnormal DNA and Mehrdad’s deep interest | data structures string suffix structures | Statement | E | Codeforces Round 383 (Div. 1) {741} | PROGRAMMING | Codeforces Round #383 editorial | 3300 | |
| 2084 | Santa Claus and a Palindrome | constructive algorithms data structures greedy | Statement | D | Technocup 2017 - Elimination Round 3 {748} | PROGRAMMING | Codeforces Round 389 (Div.2) Editorial | 2000 | |
| 1954 | New Year and Old Subsequence | data structures divide and conquer dp matrices | Statement | E | Good Bye 2016 {750} | PROGRAMMING | Good Bye 2016 — hints and codes | 2600 | |
| 13062 | PolandBall and Game | binary search data structures games greedy sortings strings | Statement | B | 8VC Venture Cup 2017 - Elimination Round {755} | PROGRAMMING | 8VC Venture Cup 2017 — Elimination Round [Editorial] | 1200 | |
| 2479 | Felicity is Coming! | data structures hashing sortings strings | Statement | C | Codecraft-17 and Codeforces Round 391 (Div. 1 + Div. 2, combined) {757} | PROGRAMMING | CodeCraft-17 and Codeforces Round #391 (Div. 1 + Div. 2, combined) Editorial | 1900 | |
| 752 | Dasha and Photos | brute force data structures dp implementation | Statement | F | Codeforces Round 394 (Div. 2) {761} | PROGRAMMING | Codeforces Round #394 (Div. 2) [Editorial] | 2900 | |
| 197 | Rap God | data structures dfs and similar hashing strings trees | Statement | D | Codeforces Round 406 (Div. 1) {786} | PROGRAMMING | Codeforces Round #406 Editorial | 3300 | |
| 10177 | Minimal string | data structures greedy strings | Statement | C | Educational Codeforces Round 19 {797} | PROGRAMMING | 51588 | 1700 | |
| 4366 | String Reconstruction | data structures greedy sortings strings | Statement | A | Codeforces Round 423 (Div. 1, rated, based on VK Cup Finals) {827} | PROGRAMMING | Codeforces Round #423 Analysis | 1700 | |
| 1820 | DNA Evolution | data structures strings | Statement | C | Codeforces Round 423 (Div. 1, rated, based on VK Cup Finals) {827} | PROGRAMMING | Codeforces Round #423 Analysis | 2200 | |
| 297 | Mahmoud and Ehab and the final stage | data structures strings | Statement | F | Codeforces Round 435 (Div. 2) {862} | PROGRAMMING | Codeforces round #435 editorial | 2800 | |
| 2086 | Letters Removing | data structures strings | Statement | F | Codeforces Round 452 (Div. 2) {899} | PROGRAMMING | Codeforces Round #452 (Div.2) Editorial | 2200 | |
| 1446 | Maximum Questions | data structures dp strings | Statement | E | Codeforces Round 450 (Div. 2) {900} | PROGRAMMING | Codeforces Round #450(Div. 2). Editorial. | 2300 | |
| 2600 | 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 | |
| 197 | Upside Down | data structures string suffix structures strings trees | Statement | E | Codeforces Round 459 (Div. 1) {917} | PROGRAMMING | Codeforces Round #459 Editorial | 3000 | |
| 4820 | Perfect Security | data structures greedy strings trees | Statement | C | VK Cup 2018 - Round 1 {923} | PROGRAMMING | VK Cup 2018 Round 1 and CF Round #470 (div. 1 & 2) editorial | 1900 | |
| 2009 | Short Code | data structures dp greedy strings trees | Statement | E | Codeforces Round 476 (Div. 2) [Thanks, Telegram!] {965} | PROGRAMMING | Analysis of Codeforces Round #476 (Div. 2) [Thanks, Telegram!] | 2500 | |
| 2264 | 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 |
| 1368 | Security | data structures string suffix structures | Statement | H | Manthan, Codefest 18 (rated, Div. 1 + Div. 2) {1037} | PROGRAMMING | Tutorial | 2900 | |
| 329 | Speckled Band | data structures divide and conquer hashing string suffix structures strings | Statement | G | Codeforces Round 519 by Botan Investments {1043} | PROGRAMMING | Codeforces Round #519 Editorial | 3500 | |
| 236 | Moonwalk challenge | data structures strings trees | Statement | J | Bubble Cup 11 - Finals [Online Mirror, Div. 1] {1045} | PROGRAMMING | E | 3000 | |
| 1316 | Vasya and Big Integers | binary search data structures dp hashing strings | Statement | E | Educational Codeforces Round 51 (Rated for Div. 2) {1051} | PROGRAMMING | Educational Codeforces Round 51 Editorial | 2500 | |
| 2924 | Check Transcription | brute force data structures hashing strings | Statement | E | Mail.Ru Cup 2018 Round 3 {1056} | PROGRAMMING | Mail.Ru Cup 2018 Round 3 Editorial | 2100 | |
| 313 | Detect Robots | data structures strings | Statement | H | Mail.Ru Cup 2018 Round 3 {1056} | PROGRAMMING | Mail.Ru Cup 2018 Round 3 Editorial | 3100 | |
| 1154 | String Journey | data structures dp string suffix structures | Statement | F | Codeforces Round 516 (Div. 1, by Moscow Team Olympiad) {1063} | PROGRAMMING | Editorial | 3000 | |
| 1165 | Yet Another LCP Problem | data structures string suffix structures | Statement | G | Educational Codeforces Round 53 (Rated for Div. 2) {1073} | PROGRAMMING | 62742 | 2700 | |
| 134 | Palindromic Magic | data structures hashing strings | Statement | H | Avito Cool Challenge 2018 {1081} | PROGRAMMING | 63888 | 3500 | |
| 1031 | Morse Code | binary search data structures dp hashing sortings string suffix structures strings | Statement | C | Codeforces Round 542 [Alex Lopashev Thanks-Round] (Div. 1) {1129} | PROGRAMMING | 65520 | 2300 | |
| 4608 | Beautiful Lyrics | data structures greedy strings | Statement | C | Codeforces Round 566 (Div. 2) {1182} | PROGRAMMING | 67614 | 1700 | |
| 10544 | RGB Substring (hard version) | data structures dp implementation two pointers | Statement | D2 | Codeforces Round 575 (Div. 3) {1196} | PROGRAMMING | Editorial | 1600 | |
| 2797 | You Are Given a WASD-string... | brute force data structures dp greedy implementation math strings | Statement | C | Educational Codeforces Round 70 (Rated for Div. 2) {1202} | PROGRAMMING | 68972 | 2100 | |
| 3425 | Kirk and a Binary String (hard version) | data structures greedy math strings | Statement | D2 | Codeforces Round 581 (Div. 2) {1204} | PROGRAMMING | 69244 | 2100 | |
| 1306 | Indie Album | data structures dfs and similar hashing string suffix structures strings trees | Statement | G | Educational Codeforces Round 71 (Rated for Div. 2) {1207} | PROGRAMMING | Educational Codeforces Round 71 Editorial | 2600 | |
| 1421 | Koala and Notebook | data structures dfs and similar graphs shortest paths strings trees | Statement | F | Codeforces Round 584 - Dasha Code Championship - Elimination Round (rated, open for everyone, Div. 1 + Div. 2) {1209} | PROGRAMMING | 69791 | 2600 | |
| 3118 | Unstable String Sort | data structures dfs and similar dsu graphs greedy implementation strings | Statement | F | Codeforces Round 582 (Div. 3) {1213} | PROGRAMMING | Codeforces Round #582 (Div. 3) Editorial | 2400 | |
| 500 | Find String in a Grid | data structures dp strings trees | Statement | D | 2019-2020 ICPC, Asia Jakarta Regional Contest (Online Mirror, ICPC Rules, Teams Preferred) {1252} | PROGRAMMING | T | 2900 | |
| 699 | Fedya the Potter Strikes Back | data structures strings | Statement | E | Codeforces Round 612 (Div. 1) {1286} | PROGRAMMING | Codeforces Round #612 - Editorial | 3200 | |
| 7402 | Irreducible Anagrams | binary search constructive algorithms data structures strings two pointers | Statement | B | Codeforces Round 616 (Div. 1) {1290} | PROGRAMMING | 1000.0 | Codeforces Round #616 Editorial | 1900 |
| 15823 | Yet Another Walking Robot | data structures implementation | Statement | C | Codeforces Round 617 (Div. 3) {1296} | PROGRAMMING | Codeforces Round #617 (Div. 3) Editorial | 1500 | |
| 1167 | Autocompletion | data structures dfs and similar dp | Statement | G | Educational Codeforces Round 83 (Rated for Div. 2) {1312} | PROGRAMMING | 74640 | ||
| 781 | Concatenation with intersection | data structures hashing strings two pointers | Statement | E | Codeforces Round 622 (Div. 2) {1313} | PROGRAMMING | 2500.0 | Editorial | 2800 |
| 1728 | Reachable Strings | data structures hashing string suffix structures strings strings | Statement | D | Codeforces Round 625 (Div. 1, based on Technocup 2020 Final Round) {1320} | PROGRAMMING | 2000.0 | Codeforces Round #625 Editorial | |
| 30863 | Frog Jumps | binary search data structures greedy implementation | Statement | C | Codeforces Round 627 (Div. 3) {1324} | PROGRAMMING | Codeforces Round #627 (Div. 3) Editorial | ||
| 5282 | Binary Subsequence Rotation | binary search data structures dp greedy implementation | Statement | E | Codeforces Round 651 (Div. 2) {1370} | PROGRAMMING | 2500.0 | Editorial — Codeforces Round #651 | |
| 21900 | Prefix Flip (Easy Version) | constructive algorithms data structures strings | Statement | A1 | Codeforces Round 658 (Div. 1) {1381} | PROGRAMMING | 500.0 | Codeforces Round #658 Editorial | 1300 |
| 14501 | Prefix Flip (Hard Version) | constructive algorithms data structures strings two pointers | Statement | A2 | Codeforces Round 658 (Div. 1) {1381} | PROGRAMMING | 500.0 | Codeforces Round #658 Editorial | 1700 |
| 1146 | Strange Operation | data structures dp | Statement | E | Codeforces Round 659 (Div. 1) {1383} | PROGRAMMING | 2000.0 | Codeforces Round #659 Editorial | |
| 6299 | Perform Easily | data structures dp implementation sortings two pointers | Statement | C | Technocup 2021 - Elimination Round 1 {1413} | PROGRAMMING | 1500.0 | Codeforces Round 679 (Div. 1, Div. 2) and Technocup Round 1 editorial | |
| 5184 | XOR Inverse | bitmasks data structures divide and conquer greedy strings trees | Statement | C | Codeforces Round 673 (Div. 1) {1416} | PROGRAMMING | 1250.0 | Codeforces Round #673 Editorial | 2000 |
| 2646 | Fruit Sequences | binary search data structures divide and conquer dp | Statement | F | Codeforces Raif Round 1 (Div. 1 + Div. 2) {1428} | PROGRAMMING | 1750.0 | Codeforces Raif Round 1 Editorial | |
| 7422 | String Reversal | data structures greedy strings | Statement | E | Educational Codeforces Round 96 (Rated for Div. 2) {1430} | PROGRAMMING | Educational Codeforces Round 96 — Editorial | ||
| 1357 | Death DBMS | data structures hashing string suffix structures strings trees | Statement | G | Educational Codeforces Round 97 (Rated for Div. 2) {1437} | PROGRAMMING | 84149 | ||
| 21276 | Two Brackets | data structures greedy | Statement | C | Educational Codeforces Round 98 (Rated for Div. 2) {1452} | PROGRAMMING | 84847 | ||
| 2835 | Pattern Matching | bitmasks data structures dfs and similar graphs sortings strings | Statement | E | Educational Codeforces Round 103 (Rated for Div. 2) {1476} | PROGRAMMING | 87356 | ||
| 17661 | Maximum width | data structures dp greedy two pointers | Statement | C | Codeforces Round 704 (Div. 2) {1492} | PROGRAMMING | 1500.0 | Codeforces Round #704 Editorial | |
| 4918 | Maximize the Remaining String | brute force data structures dp greedy strings two pointers | Statement | G | Codeforces Round 710 (Div. 3) {1506} | PROGRAMMING | Editorial | ||
| 603 | Chainword | data structures dp math matrices strings | Statement | F | Educational Codeforces Round 107 (Rated for Div. 2) {1511} | PROGRAMMING | 89634 | ||
| 2849 | Kill Anton | brute force constructive algorithms data structures math strings | Statement | D | Codeforces Round 723 (Div. 2) {1526} | PROGRAMMING | 2250.0 | Codeforces Round #723 (Div. 2) Editorial | |
| 722 | String Distance | binary search data structures hashing string suffix structures strings | Statement | F | Educational Codeforces Round 110 (Rated for Div. 2) {1535} | PROGRAMMING | 91481 | ||
| 6366 | Erase and Extend (Hard Version) | binary search data structures greedy hashing string suffix structures strings | Statement | E2 | Codeforces Round 726 (Div. 2) {1537} | PROGRAMMING | 1750.0 | Codeforces Round #726 (Div.2) Editorial | |
| 3275 | Funny Substrings | brute force data structures hashing implementation strings | Statement | E | Codeforces Round 725 (Div. 3) {1538} | PROGRAMMING | Codeforces Round #725 (Div. 3) Editorial | ||
| 1946 | Stringforces | binary search bitmasks data structures dp greedy strings two pointers | Statement | E | Educational Codeforces Round 111 (Rated for Div. 2) {1550} | PROGRAMMING | Educational Codeforces Round 111 Editorial | ||
| 961 | Jumping Around | data structures divide and conquer dp dsu graphs shortest paths trees | Statement | F | Educational Codeforces Round 111 (Rated for Div. 2) {1550} | PROGRAMMING | Educational Codeforces Round 111 Editorial | ||
| 20 | Chainword | *special data structures strings | Statement | H | Kotlin Heroes: Practice 8 {1570} | PROGRAMMING | |||
| 5278 | Another Sorting Problem | data structures sortings strings | Statement | A | COMPFEST 13 - Finals Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1575} | PROGRAMMING | COMPFEST 13 — Editorial | ||
| 25309 | Grandma Capa Knits a Scarf | data structures greedy strings two pointers | Statement | C | Codeforces Round 750 (Div. 2) {1582} | PROGRAMMING | 1500.0 | Codeforces Round #750 (Div.2) Editorial | |
| 1934 | Changing Brackets | data structures greedy | Statement | G | Codeforces Round 748 (Div. 3) {1593} | PROGRAMMING | Editorial for Codeforces Round #748 (Div.3) | ||
| 1675 | RBS | binary search bitmasks data structures dp | Statement | F | Educational Codeforces Round 115 (Rated for Div. 2) {1598} | PROGRAMMING | 95890 | ||
| 309 | Alphabetic Tree | binary search data structures dfs and similar hashing string suffix structures strings trees | Statement | G | Codeforces Round 758 (Div.1 + Div. 2) {1608} | PROGRAMMING | 2750.0 | Editorial of Codeforces Round #758 (Div.1 + Div. 2) | |
| 2761 | Lexicographically Small Enough | data structures greedy strings | Statement | E | Good Bye 2021: 2022 is NEAR {1616} | PROGRAMMING | 2500.0 | Good Bye 2021 -- Editorial | 2200 |
| 1300 | Middle Duplication | data structures dfs and similar greedy strings trees | Statement | E | Codeforces Round 763 (Div. 2) {1623} | PROGRAMMING | 2750.0 | Codeforces Round #763 (Div. 2) Editorial | |
| 1195 | Cats on the Upgrade (easy version) | data structures dfs and similar divide and conquer dp graphs trees | Statement | E1 | Codeforces Round 765 (Div. 2) {1625} | PROGRAMMING | 2000.0 | Editorial of Codeforces Round #765 (Div. 2) | |
| 732 | Cats on the Upgrade (hard version) | data structures dfs and similar graphs trees | Statement | E2 | Codeforces Round 765 (Div. 2) {1625} | PROGRAMMING | 1250.0 | Editorial of Codeforces Round #765 (Div. 2) | |
| 3364 | Tyler and Strings | combinatorics data structures implementation strings | Statement | C | Codeforces Round 775 (Div. 1, based on Moscow Open Olympiad in Informatics) {1648} | PROGRAMMING | 1500.0 | Codeforces Round #775 Editorial | |
| 1527 | Minimal String Xoration | bitmasks data structures divide and conquer hashing strings | Statement | F | Codeforces Round 778 (Div. 1 + Div. 2, based on Technocup 2022 Final Round) {1654} | PROGRAMMING | 3000.0 | Editorial of Codeforces Round #778 (Div. 1 + Div. 2, based on Technocup 2022 Final Round) | 2800 |
| 3211 | Promising String (hard version) | data structures implementation math strings | Statement | F2 | Codeforces Round 780 (Div. 3) {1660} | PROGRAMMING | Codeforces Round #780 (Div. 3) Editorial | ||
| 21804 | 2-Letter Strings | data structures math strings | Statement | E | Codeforces Round 784 (Div. 4) {1669} | PROGRAMMING | 102101 | 1200 | |
| 15926 | awoo's Favorite Problem | constructive algorithms data structures dp greedy implementation strings two pointers | Statement | C | Educational Codeforces Round 130 (Rated for Div. 2) {1697} | PROGRAMMING | 103835 | ||
| 9594 | Equate Multisets | constructive algorithms data structures graph matchings greedy math number theory | Statement | F | Codeforces Round 805 (Div. 3) {1702} | PROGRAMMING | 104763 | ||
| 29720 | Double Strings | brute force data structures strings | Statement | D | Codeforces Round 806 (Div. 4) {1703} | PROGRAMMING | 104786 | ||
| 3547 | Fibonacci Strings | brute force data structures greedy implementation math number theory | Statement | B | Codeforces Round 814 (Div. 1) {1718} | PROGRAMMING | 1250.0 | Codeforces Round #814 (Div. 1, Div. 2) Editorial | |
| 2287 | Xor-Subsequence (hard version) | bitmasks data structures dp strings trees | Statement | D2 | Codeforces Round 815 (Div. 2) {1720} | PROGRAMMING | 1000.0 | Codeforces Round #815 (Div. 2) Editorial | |
| 2664 | 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 | ||
| 37004 | Word Game | data structures implementation | Statement | C | Codeforces Round 817 (Div. 4) {1722} | PROGRAMMING | 106478 | 800 | |
| 321 | Palindrome Addicts | data structures strings | Statement | H | Codeforces Global Round 22 {1738} | PROGRAMMING | 4000.0 | Editorial of Codeforces Global Round <strong>22</strong> | |
| 673 | Keyboard Design | bitmasks data structures dp string suffix structures strings | Statement | F | Educational Codeforces Round 136 (Rated for Div. 2) {1739} | PROGRAMMING | Educational Codeforces Round 136 Editorial | ||
| 1706 | Bracket Cost | binary search data structures divide and conquer dp greedy strings | Statement | E | CodeTON Round 3 (Div. 1 + Div. 2, Rated, Prizes!) {1750} | PROGRAMMING | 2250.0 | CodeTON Round 3 (Div. 1 + Div. 2) Editorial | |
| 1675 | Hossam and Range Minimum Query | binary search bitmasks data structures hashing probabilities strings trees | Statement | F | Codeforces Round 837 (Div. 2) {1771} | PROGRAMMING | 3500.0 | Codeforces Round #837 (Div. 2) Editorial | |
| 1466 | Comfortably Numb | binary search bitmasks data structures divide and conquer dsu strings trees two pointers | Statement | F | Codeforces Round 845 (Div. 2) and ByteRace 2023 {1777} | PROGRAMMING | 2750.0 | Codeforces Round #845 (Div. 2) and ByteRace 2023 Editorial | |
| 8361 | Fixed Prefix Permutations | binary search data structures math sortings strings | Statement | D | Educational Codeforces Round 142 (Rated for Div. 2) {1792} | PROGRAMMING | 111835 | ||
| 30255 | Remove Two Letters | data structures greedy hashing strings | Statement | D | Codeforces Round 855 (Div. 3) {1800} | PROGRAMMING | Codeforces Round 855 (Div. 3) Editorial | ||
| 741 | A task for substrings | data structures string suffix structures strings | Statement | G | Codeforces Round 857 (Div. 1) {1801} | PROGRAMMING | 3500.0 | Codeforces Round #857 Editorial | |
| 61398 | Odd Queries | data structures implementation | Statement | D | Codeforces Round 859 (Div. 4) {1807} | PROGRAMMING | 114143 | ||
| 4000 | Monsters | brute force data structures dfs and similar dsu graphs implementation trees | Statement | E | CodeTON Round 4 (Div. 1 + Div. 2, Rated, Prizes!) {1810} | PROGRAMMING | 2000.0 | Editorial of CodeTON Round 4 (Div. 1 + Div. 2, Rated, Prizes!) | |
| 221 | Willy-nilly, Crack, Into Release! | data structures dp | Statement | F | Codeforces Round 866 (Div. 1) {1819} | PROGRAMMING | 3000.0 | Codeforces Round #866 (Div.1, Div.2, based on Lipetsk Team Olympiad) Editorial | |
| 1768 | Palindrome Partition | binary search brute force data structures dp hashing strings | Statement | C | Codeforces Round 873 (Div. 1) {1827} | PROGRAMMING | 1500.0 | Codeforces Round #873 (Div. 1 & 2) Editorial | 2600 |
| 3782 | Bracket Walk | constructive algorithms data structures implementation sortings strings | Statement | D | Codeforces Round 877 (Div. 2) {1838} | PROGRAMMING | 1750.0 | Codeforces Round #877 (Div. 2) Editorial | |
| 9569 | Character Blocking | data structures implementation | Statement | E | Codeforces Round 878 (Div. 3) {1840} | PROGRAMMING | Codeforces Round #878 (Div.3) Editorial | ||
| 2244 | Omsk Metro (hard version) | data structures dfs and similar divide and conquer dp implementation math trees | Statement | F2 | Codeforces Round 881 (Div. 3) {1843} | PROGRAMMING | Codeforces Round #881 (Div. 3) Editorial | ||
| 6488 | Omsk Metro (simple version) | data structures dfs and similar dp greedy math trees | Statement | F1 | Codeforces Round 881 (Div. 3) {1843} | PROGRAMMING | Codeforces Round #881 (Div. 3) Editorial | ||
| 4313 | Professor Higashikata | brute force data structures dsu greedy implementation sortings | Statement | D | Codeforces Round 882 (Div. 2) {1847} | PROGRAMMING | 2000.0 | Tutorial | |
| 12743 | Binary String Copying | binary search brute force data structures hashing strings | Statement | C | Educational Codeforces Round 152 (Rated for Div. 2) {1849} | PROGRAMMING | 118752 | ||
| 7793 | Lisa and the Martians | bitmasks data structures greedy math sortings strings trees | Statement | F | Codeforces Round 888 (Div. 3) {1851} | PROGRAMMING | 118667 | ||
| 12485 | Queries for the Array | data structures dfs and similar implementation strings trees | Statement | C | Educational Codeforces Round 154 (Rated for Div. 2) {1861} | PROGRAMMING | Educational Codeforces Round 154 Editorial | ||
| 3122 | Guess Game | bitmasks combinatorics constructive algorithms data structures games math probabilities strings trees | Statement | E | Harbour.Space Scholarship Contest 2023-2024 (Div. 1 + Div. 2) {1864} | PROGRAMMING | 2000.0 | Harbour.Space Scholarship Contest 2023-2024 (Div. 1 + Div. 2) Editorial | |
| 3017 | Anya and the Mysterious String | binary search data structures implementation | Statement | G | Codeforces Round 903 (Div. 3) {1881} | PROGRAMMING | 121327 | ||
| 1325 | Split | binary search data structures divide and conquer math two pointers | Statement | D | Codeforces Round 905 (Div. 1) {1887} | PROGRAMMING | 1250.0 | Codeforces Round #905 (Div. 1, Div. 2, Div. 3) Editorial | |
| 7111 | Ones and Twos | data structures math two pointers | Statement | D | CodeTON Round 7 (Div. 1 + Div. 2, Rated, Prizes!) {1896} | PROGRAMMING | 2000.0 | CodeTON Round 7 (Div. 1 + Div. 2, Rated, Prizes!) Editorial | |
| 2796 | Sofia and Strings | data structures greedy strings | Statement | E | Codeforces Round 910 (Div. 2) {1898} | PROGRAMMING | 2000.0 | Editorial for Codeforces Round #910 (Div. 2) | |
| 5889 | Collapsing Strings | binary search data structures dfs and similar hashing strings trees | Statement | E | Educational Codeforces Round 159 (Rated for Div. 2) {1902} | PROGRAMMING | Educational Codeforces Round 159 Editorial | ||
| 5849 | Set To Max (Hard Version) | binary search constructive algorithms data structures dsu greedy implementation sortings two pointers | Statement | D2 | Codeforces Round 914 (Div. 2) {1904} | PROGRAMMING | 750.0 | Codeforces Round 914 (Div. 2) Editorial | |
| 14432 | Largest Subsequence | data structures greedy strings | Statement | C | Codeforces Round 915 (Div. 2) {1905} | PROGRAMMING | 1500.0 | Codeforces Round 915 (Div. 2) Editorial | |
| 31017 | YetnotherrokenKeoard | data structures implementation strings | Statement | B | Codeforces Round 913 (Div. 3) {1907} | PROGRAMMING | Codeforces Round 913 (Div. 3) Editorial | ||
| 610 | Palindromic Problem | binary search data structures hashing strings | Statement | F | Educational Codeforces Round 160 (Rated for Div. 2) {1913} | PROGRAMMING | 123493 | ||
| 36946 | Romantic Glasses | data structures greedy math | Statement | E | Codeforces Round 918 (Div. 4) {1915} | PROGRAMMING | 123952 | ||
| 18869 | Find B | constructive algorithms data structures greedy | Statement | C | Educational Codeforces Round 162 (Rated for Div. 2) {1923} | PROGRAMMING | Educational Codeforces Round 162 Editorial | ||
| 4675 | Non-Palindromic Substring | data structures hashing implementation math strings | Statement | B | Codeforces Round 934 (Div. 1) {1943} | PROGRAMMING | 1250.0 | Codeforces Round #934 (Div1, Div2) Editorial | |
| 32799 | Progressive Square | constructive algorithms data structures implementation sortings | Statement | B | Codeforces Round 938 (Div. 3) {1955} | PROGRAMMING | 128243 | ||
| 5442 | Division + LCP (easy version) | binary search data structures dp hashing string suffix structures strings | Statement | G1 | Codeforces Round 943 (Div. 3) {1968} | PROGRAMMING | 129096 | 1900 | |
| 2644 | Division + LCP (hard version) | binary search brute force data structures dp hashing math string suffix structures strings | Statement | G2 | Codeforces Round 943 (Div. 3) {1968} | PROGRAMMING | 129096 | 2200 | |
| 2956 | Chain Queries | binary search data structures dfs and similar implementation trees | Statement | E | Codeforces Round 947 (Div. 1 + Div. 2) {1975} | PROGRAMMING | 2000.0 | editorial_zh.pdf | 2100 |
| 5927 | Invertible Bracket Sequences | binary search combinatorics data structures divide and conquer implementation two pointers | Statement | D | Educational Codeforces Round 166 (Rated for Div. 2) {1976} | PROGRAMMING | Educational Codeforces Round 166 Editorial | ||
| 4683 | Computing Machine | data structures dp greedy implementation | Statement | E | Codeforces Round 953 (Div. 2) {1978} | PROGRAMMING | 2000.0 | 130527 | |
| 1782 | Yasya and the Mysterious Tree | bitmasks data structures dfs and similar graphs strings trees | Statement | G | Codeforces Round 950 (Div. 3) {1980} | PROGRAMMING | 130135 | ||
| 13284 | Permutation of Rows and Columns | constructive algorithms data structures hashing math matrices sortings | Statement | E | Codeforces Round 950 (Div. 3) {1980} | PROGRAMMING | 130135 | ||
| 10183 | Beauty of the mountains | brute force data structures implementation math number theory | Statement | D | Codeforces Round 955 (Div. 2, with prizes from NEAR!) {1982} | PROGRAMMING | 1750.0 | 130839 | |
| 32024 | Numeric String Template | data structures strings | Statement | C | Codeforces Round 966 (Div. 3) {2000} | PROGRAMMING | 132689 | ||
| 13546 | Colored Portals | binary search data structures graphs greedy shortest paths | Statement | D | Educational Codeforces Round 169 (Rated for Div. 2) {2004} | PROGRAMMING | Educational Codeforces Round 169 Editorial | ||
| 427 | Substring Compression | data structures matrices | Statement | G | Educational Codeforces Round 169 (Rated for Div. 2) {2004} | PROGRAMMING | Educational Codeforces Round 169 Editorial | ||
| 13897 | Alternating String | brute force data structures dp greedy strings | Statement | E | Codeforces Round 970 (Div. 3) {2008} | PROGRAMMING | Codeforces Round 970 (Div. 3) Editorial | ||
| 1217 | Orangutan Approved Subarrays | binary search brute force data structures greedy two pointers | Statement | F | Codeforces Round 979 (Div. 2) {2030} | PROGRAMMING | 2500.0 | Codeforces Round 979 Editorial | |
| 22514 | Anya and 1100 | brute force data structures implementation | Statement | C | Codeforces Round 984 (Div. 3) {2036} | PROGRAMMING | Codeforces Round 984 (Div. 3) Editorial | ||
| 761 | Polyathlon | data structures hashing string suffix structures strings | Statement | I | 2024-2025 ICPC, NERC, Southern and Volga Russian Regional Contest (Unrated, Online Mirror, ICPC Rules, Preferably Teams) {2038} | PROGRAMMING | 2500 | ||
| 690 | Auto Complete | data structures implementation sortings strings trees | Statement | I | 2024 ICPC Asia Taichung Regional Contest (Unrated, Online Mirror, ICPC Rules, Preferably Teams) {2041} | PROGRAMMING | Problem Analysis and Hints (PDF) | ||
| 257 | Kevin and Strange Operation | data structures dp | Statement | H | Codeforces Global Round 28 {2048} | PROGRAMMING | 2750.0 | Tutorial | |
| 2309 | Kevin and Binary String (Easy Version) | binary search brute force data structures dp greedy implementation strings two pointers | Statement | F1 | 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 | |
| 11076 | Kevin and Numbers | brute force data structures greedy implementation math | Statement | D | IAEPC Preliminary Contest (Codeforces Round 999, Div. 1 + Div. 2) {2061} | PROGRAMMING | 1500.0 | IAEPC Preliminary Contest (Codeforces Round 999, Div. 1 + Div. 2) Editorial | |
| 2036 | Bro Thinks He's Him | combinatorics data structures dp matrices | Statement | H | Codeforces Round 1003 (Div. 4) {2065} | PROGRAMMING | Video Tutorial | ||
| 1911 | Game with Binary String | data structures divide and conquer games greedy math | Statement | E | Educational Codeforces Round 175 (Rated for Div. 2) {2070} | PROGRAMMING | Video Tutorial | ||
| 4003 | Shorten the Array | binary search brute force data structures dfs and similar greedy strings trees two pointers | Statement | G | Codeforces Round 1016 (Div. 3) {2093} | PROGRAMMING | Codeforces Round 1016 (Div. 3) Editorial | ||
| 8356 | Unpleasant Strings | binary search data structures dp greedy strings | Statement | E | Educational Codeforces Round 178 (Rated for Div. 2) {2104} | PROGRAMMING | Educational Codeforces Round 178 Editorial | ||
| 5507 | Changing the String | binary search data structures greedy implementation sortings strings | Statement | E | Educational Codeforces Round 179 (Rated for Div. 2) {2111} | PROGRAMMING | Educational Codeforces Round 179 Editorial | ||
| 5502 | Gangsta | data structures divide and conquer math sortings | Statement | G | Codeforces Round 1032 (Div. 3) {2121} | PROGRAMMING | Codeforces Round 1032 (Div. 3) Editorial | ||
| 3424 | Modular Sorting | brute force data structures math number theory | Statement | G | Codeforces Round 1034 (Div. 3) {2123} | PROGRAMMING | Codeforces Round 1034 (Div. 3) Editorial | ||
| 4826 | Unjust Binary Life | binary search binary search data structures greedy greedy math two pointers | Statement | F | Codeforces Round 1042 (Div. 3) {2131} | PROGRAMMING | Codeforces Round 1042 (Div. 3) Editorial | ||
| 52 | PalindromePalindrome | data structures strings | Statement | H | Codeforces Global Round 30 (Div. 1 + Div. 2) {2164} | PROGRAMMING | 5500.0 | Codeforces Global Round 30 Editorial | |
| 7656 | Rae Taylor and Trees (hard version) | binary search constructive algorithms data structures dp dsu implementation trees | Statement | F | Codeforces Round 1065 (Div. 3) {2171} | PROGRAMMING | Codeforces Round 1065 (Div. 3) Editorial | ||
| 12391 | Rae Taylor and Trees (easy version) | binary search data structures dp dsu greedy implementation trees | Statement | D | Codeforces Round 1065 (Div. 3) {2171} | PROGRAMMING | Codeforces Round 1065 (Div. 3) Editorial | ||
| 1184 | Jumping Man | combinatorics data structures dp trees | Statement | F | Hello 2026 {2183} | PROGRAMMING | 2750.0 | ||
| 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 | |
| 239 | Fuzzy Concatenation (Hard version) | binary search data structures dp greedy string suffix structures | Statement | E2 | Codeforces Round 1079 (Div. 1) {2196} | PROGRAMMING | 1000.0 | Tutorial | |
| 14144 | Palindromex | binary search brute force constructive algorithms data structures greedy implementation two pointers | Statement | D | Codeforces Round 1096 (Div. 3) {2227} | PROGRAMMING | Codeforces Round 1096 (Div. 3) — Editorial | ||
| 7960 | Masha and the Garland | data structures dp strings | Statement | E | Codeforces Round 1109 (Div. 3) {2244} | PROGRAMMING | Codeforces Round 1109 (Div. 3) Editorial |