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Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 1354 | Deletion of Repeats | greedy hashing string suffix structures | Statement | C | Codeforces Beta Round 19 {19} | PROGRAMMING | Code Force Beta Round 19 Solution | 2200 | |
| 929 | 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 | |
| 877 | Genetic engineering | dp string suffix structures trees | Statement | C | Yandex.Algorithm 2011: Round 2 {86} | PROGRAMMING | Problemset analysis (Yandex, Round 2) | 2400 | |
| 1444 | String | string suffix structures | Statement | D | Codeforces Beta Round 92 (Div. 1 Only) {123} | PROGRAMMING | Codeforces Beta Round #92 - Analysis | 2300 | |
| 25515 | Password | binary search dp hashing string suffix structures strings | Statement | B | Codeforces Beta Round 93 (Div. 1 Only) {126} | PROGRAMMING | Tutorial | 1800 | |
| 2893 | String | brute force constructive algorithms hashing implementation string suffix structures strings | Statement | B | Codeforces Beta Round 94 (Div. 1 Only) {128} | PROGRAMMING | 3219 | 2200 | |
| 2536 | Martian Strings | string suffix structures strings | Statement | E | Codeforces Round 106 (Div. 2) {149} | PROGRAMMING | Codeforces Round #106 (Div. 2) Tutorial | 2200 | |
| 1458 | Little Elephant and Strings | data structures implementation string suffix structures two pointers | Statement | E | Codeforces Round 129 (Div. 1) {204} | PROGRAMMING | Tutorial | 2800 | |
| 526 | Fence | binary search data structures string suffix structures | Statement | D | Codeforces Round 144 (Div. 1) {232} | PROGRAMMING | Editorial for Codeforces Round #144 | 2700 | |
| 2492 | Cyclical Quest | data structures string suffix structures strings | Statement | C | Codeforces Round 146 (Div. 1) {235} | PROGRAMMING | Codeforces Round #146 Tutorial | 2700 | |
| 521 | Good Substrings | string suffix structures | Statement | G2 | ABBYY Cup 3.0 {316} | PROGRAMMING | 2200 | ||
| 544 | Good Substrings | string suffix structures | Statement | G3 | ABBYY Cup 3.0 {316} | PROGRAMMING | 2800 | ||
| 778 | Have You Ever Heard About the Word? | greedy hashing string suffix structures strings | Statement | D | Codeforces Round 189 (Div. 1) {319} | PROGRAMMING | Codeforces Round #189 — Editorial | 2700 | |
| 490 | Xenia and String Problem | dp hashing implementation string suffix structures strings | Statement | E | Codeforces Round 207 (Div. 1) {356} | PROGRAMMING | 9210 | 2800 | |
| 2440 | Match & Catch | dp string suffix structures strings | Statement | D | Codeforces Round 244 (Div. 2) {427} | PROGRAMMING | Codeforces Round #244 (Div. 2) Editorial | 2000 | |
| 12349 | Prefixes and Suffixes | dp string suffix structures strings two pointers | Statement | D | Codeforces Round 246 (Div. 2) {432} | PROGRAMMING | Codeforces Round #246 (Div. 2) Editorial | 2000 | |
| 1206 | Valera and Swaps | constructive algorithms dsu graphs implementation math string suffix structures | Statement | D | Codeforces Round 252 (Div. 2) {441} | PROGRAMMING | Разбор Codeforces Round #252 (Div. 2) | 2300 | |
| 17474 | Suffix Structures | implementation strings | Statement | B | Codeforces Round 256 (Div. 2) {448} | PROGRAMMING | Tutorial | 1400 | |
| 1206 | 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 | |
| 10584 | MUH and Cube Walls | string suffix structures strings | Statement | D | Codeforces Round 269 (Div. 2) {471} | PROGRAMMING | Codeforces Round #269 Editorial | 2000 | |
| 1073 | Misha and LCP on Tree | binary search dfs and similar hashing string suffix structures trees | Statement | E | Codeforces Round 285 (Div. 1) {504} | PROGRAMMING | 15743 | 3000 | |
| 8240 | 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 | |
| 598 | 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 | |
| 2471 | Om Nom and Necklace | hashing string suffix structures strings | Statement | D | ZeptoLab Code Rush 2015 {526} | PROGRAMMING | ZeptoLab Code Rush 2015 — Editorial | 2200 | |
| 956 | Encoding | hashing string suffix structures strings | Statement | F | VK Cup 2015 - Round 2 (unofficial online mirror, Div. 1 only) {533} | PROGRAMMING | Разбор VK Cup Round 2 | 2400 | |
| 4791 | Tavas and Malekas | greedy hashing string suffix structures strings | Statement | D | Codeforces Round 299 (Div. 2) {535} | PROGRAMMING | Codeforces Round #299 Editorial | 2100 | |
| 2631 | Mike and Friends | data structures string suffix structures strings trees | Statement | E | Codeforces Round 305 (Div. 1) {547} | PROGRAMMING | Codeforces Round #305 Editorial | 2800 | |
| 1222 | 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 | |
| 175 | Cutting the Line | string suffix structures strings | Statement | E | Codeforces Round 330 (Div. 1) {594} | PROGRAMMING | Codeforces Round #330 (Div.1 + Div.2) Editorial | 3200 | |
| 732 | Expensive Strings | string suffix structures strings | Statement | F | Educational Codeforces Round 5 {616} | PROGRAMMING | Editorial of Educational Codeforces Round 5 | 2700 | |
| 2460 | 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 | |
| 3397 | 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 | |
| 1178 | 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 | |
| 1566 | Forensic Examination | data structures string suffix structures | Statement | E | Codeforces Round 349 (Div. 1) {666} | PROGRAMMING | Codeforces Round #349 Editorial | 3100 | |
| 3472 | Correct Bracket Sequence Editor | data structures dsu strings | Statement | E | Codeforces Round 350 (Div. 2) {670} | PROGRAMMING | Codeforces Round #350 (Div.2) Editorial | 1700 | |
| 1395 | Cool Slogans | string suffix structures strings | Statement | E | Codeforces Round 364 (Div. 1) {700} | PROGRAMMING | 46283 | 3300 | |
| 2539 | 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 | |
| 1585 | 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 | |
| 194 | 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 | |
| 1090 | Bacterial Melee | brute force combinatorics dp string suffix structures | Statement | D | 8VC Venture Cup 2017 - Final Round {756} | PROGRAMMING | 8VC Venture Cup 2017 — Final Round and Codeforces Round #393 Editorial | 2500 | |
| 1853 | Fake News (hard) | string suffix structures | Statement | G3 | Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} | PROGRAMMING | helvetic-coding-contest-2017-editorial.pdf | 2300 | |
| 1815 | Fake News (hard) | string suffix structures | Statement | I | Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} | PROGRAMMING | helvetic-coding-contest-2017-editorial.pdf | 2400 | |
| 1095 | Liar | binary search dp hashing string suffix structures | Statement | E | Codeforces Round 422 (Div. 2) {822} | PROGRAMMING | Codeforces Round #422 (Div. 2) Editorial | 2500 | |
| 1997 | String Compression | dp hashing string suffix structures strings | Statement | F | Educational Codeforces Round 25 {825} | PROGRAMMING | Educational Codeforces Round 25 - Editorial | 2400 | |
| 1888 | Forbidden Indices | dsu string suffix structures strings | Statement | F | Educational Codeforces Round 30 {873} | PROGRAMMING | 55171 | 2300 | |
| 577 | Reverses | dp string suffix structures strings | Statement | E | Codeforces Round 454 (Div. 1, based on Technocup 2018 Elimination Round 4) {906} | PROGRAMMING | Editorial Codeforces Round 454 (and Technocup 2018 — Elimination Round 4) | 3200 | |
| 2172 | 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 | |
| 186 | Upside Down | data structures string suffix structures strings trees | Statement | E | Codeforces Round 459 (Div. 1) {917} | PROGRAMMING | Codeforces Round #459 Editorial | 3000 | |
| 1199 | Palindrome Partition | dp string suffix structures strings | Statement | G | ICM Technex 2018 and Codeforces Round 463 (Div. 1 + Div. 2, combined) {932} | PROGRAMMING | 57796 | 2900 | |
| 948 | k-substrings | binary search hashing string suffix structures | Statement | F | Educational Codeforces Round 41 (Rated for Div. 2) {961} | PROGRAMMING | Educational Codeforces Round 41 Editorial | 2700 | |
| 2782 | Frequency of String | hashing string suffix structures strings | Statement | D | Tinkoff Internship Warmup Round 2018 and Codeforces Round 475 (Div. 1) {963} | PROGRAMMING | Editorial Tinkoff Internship Warmup Round 2018 and Codeforces Round #475 (Div. 1 + Div. 2) | 2400 | |
| 1217 | Security | data structures string suffix structures | Statement | H | Manthan, Codefest 18 (rated, Div. 1 + Div. 2) {1037} | PROGRAMMING | Tutorial | 2900 | |
| 325 | 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 | |
| 1013 | String Journey | data structures dp string suffix structures | Statement | F | Codeforces Round 516 (Div. 1, by Moscow Team Olympiad) {1063} | PROGRAMMING | Editorial | 3000 | |
| 1113 | Yet Another LCP Problem | data structures string suffix structures | Statement | G | Educational Codeforces Round 53 (Rated for Div. 2) {1073} | PROGRAMMING | 62742 | 2700 | |
| 283 | Ж-function | string suffix structures strings | Statement | F | Codeforces Round 530 (Div. 1) {1098} | PROGRAMMING | 64331 | 3500 | |
| 1006 | 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 | |
| 9538 | Compress Words | brute force hashing implementation string suffix structures strings | Statement | E | Codeforces Round 578 (Div. 2) {1200} | PROGRAMMING | Codeforces Round #578 (Div. 2) Editorial | 2000 | |
| 2808 | You Are Given Some Strings... | brute force string suffix structures strings | Statement | E | Educational Codeforces Round 70 (Rated for Div. 2) {1202} | PROGRAMMING | 68972 | 2500 | |
| 1238 | 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 | |
| 139 | Permutation Concatenation | string suffix structures | Statement | G | Codeforces Global Round 6 {1266} | PROGRAMMING | Codeforces Global Round 6 Editorial | 3300 | |
| 449 | Asterisk Substrings | string suffix structures | Statement | F | Codeforces Round 606 (Div. 1, based on Technocup 2020 Elimination Round 4) {1276} | PROGRAMMING | Technocup 2020 — Elimination Round 4 + Codeforces Round 606: Editorial | 3300 | |
| 15766 | Yet Another Walking Robot | data structures implementation | Statement | C | Codeforces Round 617 (Div. 3) {1296} | PROGRAMMING | Codeforces Round #617 (Div. 3) Editorial | 1500 | |
| 11 | Who needs suffix structures? | Statement | H | AIM Tech Poorly Prepared Contest (unrated, funny, Div. 1 preferred) {1302} | PROGRAMMING | 73599 | |||
| 1717 | 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 | |
| 13357 | Prefix-Suffix Palindrome (Easy version) | hashing string suffix structures strings | Statement | D1 | Codeforces Global Round 7 {1326} | PROGRAMMING | 1000.0 | 74961 | 1500 |
| 11897 | Prefix-Suffix Palindrome (Hard version) | greedy hashing string suffix structures strings | Statement | D2 | Codeforces Global Round 7 {1326} | PROGRAMMING | 1000.0 | 74961 | 1800 |
| 533 | Letters and Question Marks | bitmasks dp string suffix structures | Statement | G | Educational Codeforces Round 84 (Rated for Div. 2) {1327} | PROGRAMMING | Educational Codeforces Round 84 Editorial | 2900 | |
| 449 | Twilight and Ancient Scroll (easier version) | dp hashing implementation string suffix structures strings | Statement | E1 | Codeforces Round 662 (Div. 2) {1393} | PROGRAMMING | 1500.0 | Codeforces Round #662 Editorial | |
| 446 | Twilight and Ancient Scroll (harder version) | dp implementation string suffix structures strings | Statement | E2 | Codeforces Round 662 (Div. 2) {1393} | PROGRAMMING | 1500.0 | Codeforces Round #662 Editorial | |
| 1188 | x-prime Substrings | bitmasks dp greedy number theory string suffix structures strings | Statement | F | Educational Codeforces Round 94 (Rated for Div. 2) {1400} | PROGRAMMING | 81942 | ||
| 1283 | Death DBMS | data structures hashing string suffix structures strings trees | Statement | G | Educational Codeforces Round 97 (Rated for Div. 2) {1437} | PROGRAMMING | 84149 | ||
| 2203 | 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 | ||
| 71 | Build From Suffixes | *special combinatorics data structures | Statement | H | Kotlin Heroes: Episode 6 {1488} | PROGRAMMING | 88522 | ||
| 918 | Matrix Sorting | bitmasks constructive algorithms dfs and similar greedy hashing string suffix structures two pointers | Statement | C | Codeforces Round 707 (Div. 1, based on Moscow Open Olympiad in Informatics) {1500} | PROGRAMMING | 1500.0 | Codeforces Round #707 Editorial | 2600 |
| 1508 | Oolimry and Suffix Array | combinatorics constructive algorithms math string suffix structures | Statement | E | Codeforces Round 723 (Div. 2) {1526} | PROGRAMMING | 2500.0 | Codeforces Round #723 (Div. 2) Editorial | |
| 609 | String Distance | binary search data structures hashing string suffix structures strings | Statement | F | Educational Codeforces Round 110 (Rated for Div. 2) {1535} | PROGRAMMING | 91481 | ||
| 16626 | Erase and Extend (Easy Version) | binary search brute force dp greedy hashing string suffix structures strings | Statement | E1 | Codeforces Round 726 (Div. 2) {1537} | PROGRAMMING | 1250.0 | Codeforces Round #726 (Div.2) Editorial | |
| 6245 | 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 | |
| 1592 | Rescue Niwen! | dp string suffix structures strings | Statement | E | Codeforces Round 741 (Div. 2) {1562} | PROGRAMMING | 2750.0 | Editorial of Codeforces Round 741 (Div. 2) | |
| 247 | 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) | |
| 145 | Two Sequences | data structures hashing string suffix structures | Statement | I | Hello 2022 {1621} | PROGRAMMING | 4500.0 | ||
| 2577 | 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 | ||
| 641 | 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 | ||
| 20750 | Save the Magazines | constructive algorithms greedy sortings string suffix structures | Statement | C | Educational Codeforces Round 137 (Rated for Div. 2) {1743} | PROGRAMMING | Educational Codeforces Round 137 Editorial | 1100 | |
| 1009 | Delicious Dessert | math number theory string suffix structures strings | Statement | G | Codeforces Round 846 (Div. 2) {1780} | PROGRAMMING | 2500.0 | 111841 | |
| 727 | 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 | |
| 335 | Entangled Substrings | string suffix structures | Statement | F | Codeforces Round 869 (Div. 1) {1817} | PROGRAMMING | 3000.0 | Codeforces Round #869 (Div.1, Div.2) Editorial | |
| 658 | Pumping Lemma | hashing string suffix structures strings | Statement | G | Pinely Round 3 (Div. 1 + Div. 2) {1909} | PROGRAMMING | 4000.0 | Editorial of Pinely Round 3 (Div. 1 + Div. 2) | |
| 538 | Shrink-Reverse | binary search greedy string suffix structures strings | Statement | F | Educational Codeforces Round 162 (Rated for Div. 2) {1923} | PROGRAMMING | Educational Codeforces Round 162 Editorial | ||
| 5359 | 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 | |
| 2547 | 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 | |
| 3907 | ''a'' String Problem | hashing implementation math string suffix structures strings | Statement | D | Codeforces Global Round 26 {1984} | PROGRAMMING | 2500.0 | Codeforces Global Round 26 Editorial | |
| 750 | 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 | ||
| 805 | Missing Separators | dp sortings string suffix structures strings | Statement | H | 2024-2025 ICPC Asia Jakarta Regional Contest (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {2045} | PROGRAMMING | raRzKDJLPHcUnqTcwvGznwEdKiDWjEkd.pdf | 2200 | |
| 13843 | Piecing It Together | *special string suffix structures | Statement | A | April Fools Day Contest 2025 {2095} | PROGRAMMING | |||
| 31245 | Prefix Min and Suffix Max | brute force data structures | Statement | C | Codeforces Round 1034 (Div. 3) {2123} | PROGRAMMING | Codeforces Round 1034 (Div. 3) Editorial | ||
| 304 | Shuffling Cards with Problem Solver 68! | string suffix structures | Statement | H | 2025 ICPC Asia Taichung Regional Contest (Unrated, Online Mirror, ICPC Rules, Preferably Teams) {2172} | PROGRAMMING | |||
| 299 | 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 | |
| 213 | 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 | |
| 1670 | Simons and Dividing the Rhythm | dp string suffix structures strings | Statement | E | Codeforces Round 1083 (Div. 2) {2205} | PROGRAMMING | 2500.0 | Tutorial | |
| 698 | String Cutting | binary search brute force greedy hashing string suffix structures strings | Statement | F | Educational Codeforces Round 189 (Rated for Div. 2) {2225} | PROGRAMMING | Tutorial |