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Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 110845 | Registration System | data structures hashing implementation | Statement | C | Codeforces Beta Round 4 (Div. 2 Only) {4} | PROGRAMMING | 1500 | ||
| 690 | Don't fear, DravDe is kind | binary search data structures dp hashing | Statement | D | Codeforces Beta Round 28 (Codeforces format) {28} | PROGRAMMING | Codeforces Beta Round #28 (Разбор задач A и B) | 2600 | |
| 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 | |
| 2131 | Beaver | data structures dp greedy hashing strings two pointers | Statement | C | Codeforces Beta Round 71 {79} | PROGRAMMING | Codeforces Beta Round #71 Editorial | 1800 | |
| 3281 | Petr# | brute force data structures hashing strings | Statement | B | Codeforces Beta Round 86 (Div. 1 Only) {113} | PROGRAMMING | Codeforces Beta Round #86 Editorial | 1900 | |
| 1757 | Counter Attack | data structures dsu graphs hashing sortings | Statement | E | Codeforces Round 120 (Div. 2) {190} | PROGRAMMING | Codeforces Round #120 (Div.2) — editorial | 2300 | |
| 604 | The Next Good String | data structures greedy hashing strings | Statement | D | Codeforces Round 124 (Div. 1) {196} | PROGRAMMING | Codeforces Round #124 — editorial | 2600 | |
| 972 | Two Permutations | data structures hashing strings | Statement | E | Codeforces Round 131 (Div. 1) {213} | PROGRAMMING | Codeforces Round #131 Tutorial | 2600 | |
| 299 | Looking for Owls | binary search data structures geometry hashing sortings | Statement | D | Codeforces Round 203 (Div. 2) {350} | PROGRAMMING | Editorial Codeforces Round #203 (Div. 2) | 2600 | |
| 1639 | Sereja and Squares | binary search data structures hashing | Statement | D | Codeforces Round 243 (Div. 1) {425} | PROGRAMMING | Codeforces Round #243 tutorial | 2300 | |
| 1804 | Permutation | data structures divide and conquer hashing | Statement | F | MemSQL Start[c]UP 2.0 - Round 1 {452} | PROGRAMMING | MemSQL Start[c]UP 2.0 Round 1 and 2 Editorials | 2600 | |
| 2677 | LIS of Sequence | data structures dp greedy hashing math | Statement | E | Codeforces Round 277 (Div. 2) {486} | PROGRAMMING | Codeforces Round #277(Div. 2) Editorial | 2400 | |
| 8249 | 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 | |
| 2601 | Kefa and Watch | data structures hashing strings | Statement | E | Codeforces Round 321 (Div. 2) {580} | PROGRAMMING | Codeforces Round #321 Editorial | 2700 | |
| 1247 | 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 | |
| 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 | |
| 3401 | 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 | |
| 1605 | Zip-line | binary search data structures dp hashing | Statement | D | Codeforces Round 345 (Div. 1) {650} | PROGRAMMING | Codeforces Round #345: editorial | 2600 | |
| 2542 | 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 | |
| 1586 | 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 | |
| 4369 | Kostya the Sculptor | data structures hashing | Statement | D | Codeforces Round 378 (Div. 2) {733} | PROGRAMMING | Codeforces Round #378 (Div. 2) editorial | 1600 | |
| 2467 | 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 | |
| 651 | Timofey and a flat tree | data structures graphs hashing shortest paths trees | Statement | D | Codeforces Round 395 (Div. 1) {763} | PROGRAMMING | Codeforces Round #395 [Editorial] | 2800 | |
| 168 | Rap God | data structures dfs and similar hashing strings trees | Statement | D | Codeforces Round 406 (Div. 1) {786} | PROGRAMMING | Codeforces Round #406 Editorial | 3300 | |
| 2083 | The Untended Antiquity | data structures hashing | Statement | E | Codeforces Round 439 (Div. 2) {869} | PROGRAMMING | Tutorial | 2300 | |
| 2364 | Ann and Books | data structures flows hashing | Statement | F | Codeforces Round 442 (Div. 2) {877} | PROGRAMMING | 55362 | 2500 | |
| 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 | |
| 1227 | 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 | |
| 2847 | 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 | |
| 132 | Palindromic Magic | data structures hashing strings | Statement | H | Avito Cool Challenge 2018 {1081} | PROGRAMMING | 63888 | 3500 | |
| 1007 | 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 | |
| 815 | Vicky's Delivery Service | data structures dsu graphs hashing | Statement | F | Codeforces Round 561 (Div. 2) {1166} | PROGRAMMING | Codeforces Round #561 (Div. 2) Editorial | 2800 | |
| 2709 | The Number of Subpermutations | brute force data structures divide and conquer hashing math | Statement | F | Educational Codeforces Round 66 (Rated for Div. 2) {1175} | PROGRAMMING | Editorial | 2600 | |
| 1239 | 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 | |
| 2274 | Stack Exterminable Arrays | data structures divide and conquer dp hashing | Statement | F | Technocup 2020 - Elimination Round 1 {1223} | PROGRAMMING | Сodeforces Round 591 (and Technocup 2020 — Elimination Round 1) Editorial | 2600 | |
| 3281 | Let's Play the Words? | data structures hashing implementation math | Statement | D | Codeforces Round 606 (Div. 2, based on Technocup 2020 Elimination Round 4) {1277} | PROGRAMMING | Technocup 2020 — Elimination Round 4 + Codeforces Round 606: Editorial | 1800 | |
| 3409 | New Year and Conference | binary search data structures hashing sortings | Statement | D | Hello 2020 {1284} | PROGRAMMING | Hello 2020 Editorial | 2100 | |
| 726 | Concatenation with intersection | data structures hashing strings two pointers | Statement | E | Codeforces Round 622 (Div. 2) {1313} | PROGRAMMING | 2500.0 | Editorial | 2800 |
| 1719 | 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 | |
| 13549 | Eugene and an array | binary search data structures hashing implementation two pointers | Statement | C | Codeforces Round 632 (Div. 2) {1333} | PROGRAMMING | 1250.0 | Codeforces Round #632 (Div. 2) editorial | |
| 718 | Nastya and CBS | brute force data structures hashing | Statement | F | Codeforces Round 637 (Div. 1) - Thanks, Ivan Belonogov! {1340} | PROGRAMMING | 3000.0 | Codeforces Round #637 Editorial | |
| 4764 | Trash Problem | data structures hashing implementation two pointers | Statement | D | Educational Codeforces Round 95 (Rated for Div. 2) {1418} | PROGRAMMING | Unofficial Editorial for Educational Round 95 (Div. 2) | ||
| 2792 | Three Occurrences | data structures hashing two pointers | Statement | G | Educational Codeforces Round 95 (Rated for Div. 2) {1418} | PROGRAMMING | Unofficial Editorial for Educational Round 95 (Div. 2) | ||
| 1285 | Death DBMS | data structures hashing string suffix structures strings trees | Statement | G | Educational Codeforces Round 97 (Rated for Div. 2) {1437} | PROGRAMMING | 84149 | ||
| 1356 | Odd Mineral Resource | bitmasks data structures hashing probabilities trees | Statement | D | Codeforces Round 700 (Div. 1) {1479} | PROGRAMMING | 2250.0 | Editorial of Codeforces Round #700 | |
| 1924 | Square-free division (hard version) | data structures dp greedy hashing math number theory | Statement | E2 | Codeforces Round 708 (Div. 2) {1497} | PROGRAMMING | 1500.0 | Codeforces Round #708 Editorial | 2500 |
| 66309 | Same Differences | data structures hashing math | Statement | D | Codeforces Round 719 (Div. 3) {1520} | PROGRAMMING | 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 | ||
| 6255 | 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 | |
| 3243 | Funny Substrings | brute force data structures hashing implementation strings | Statement | E | Codeforces Round 725 (Div. 3) {1538} | PROGRAMMING | Codeforces Round #725 (Div. 3) Editorial | ||
| 4871 | The Strongest Build | data structures dfs and similar graphs greedy hashing implementation shortest paths | Statement | D | Educational Codeforces Round 114 (Rated for Div. 2) {1574} | PROGRAMMING | 95188 | ||
| 1585 | Red-Blue Matrix | constructive algorithms data structures hashing implementation sortings two pointers | Statement | D | Educational Codeforces Round 116 (Rated for Div. 2) {1606} | PROGRAMMING | 96454 | ||
| 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) | |
| 655 | AmShZ Wins a Bet | data structures hashing | Statement | G | Codeforces Global Round 17 {1610} | PROGRAMMING | 3250.0 | Codeforces Global Round 17 Editorial | |
| 145 | Two Sequences | data structures hashing string suffix structures | Statement | I | Hello 2022 {1621} | PROGRAMMING | 4500.0 | ||
| 1492 | 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 |
| 2579 | 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 | ||
| 6927 | Meta-set | brute force combinatorics data structures hashing math | Statement | D | Codeforces Round 824 (Div. 2) {1735} | PROGRAMMING | 1750.0 | Codeforces Round #824 — editorial | |
| 2728 | Kazaee | data structures hashing probabilities | Statement | F | Codeforces Global Round 23 {1746} | PROGRAMMING | 2500.0 | Codeforces Global Round 23 Editorial | |
| 1581 | 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 | |
| 1540 | Labeling the Tree with Distances | data structures dp hashing implementation trees | Statement | E | Codeforces Round 856 (Div. 2) {1794} | PROGRAMMING | 2750.0 | Codeforces Round 856 (Div. 2) Editorial | |
| 29793 | Remove Two Letters | data structures greedy hashing strings | Statement | D | Codeforces Round 855 (Div. 3) {1800} | PROGRAMMING | Codeforces Round 855 (Div. 3) Editorial | ||
| 3475 | Tree Master | brute force data structures dfs and similar hashing trees | Statement | E | Codeforces Round 858 (Div. 2) {1806} | PROGRAMMING | 2250.0 | Codeforces Round #858 (Div. 2) Editorial | |
| 1670 | 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 |
| 12618 | Binary String Copying | binary search brute force data structures hashing strings | Statement | C | Educational Codeforces Round 152 (Rated for Div. 2) {1849} | PROGRAMMING | 118752 | ||
| 5722 | 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 | ||
| 552 | Palindromic Problem | binary search data structures hashing strings | Statement | F | Educational Codeforces Round 160 (Rated for Div. 2) {1913} | PROGRAMMING | 123493 | ||
| 1844 | Light Bulbs (Hard Version) | combinatorics data structures dfs and similar dp dsu graphs hashing | Statement | G2 | Codeforces Round 916 (Div. 3) {1914} | PROGRAMMING | Codeforces Round 916 (Div. 3) Editorial | ||
| 31693 | Divisible Pairs | combinatorics data structures hashing math | Statement | D | Codeforces Round 925 (Div. 3) {1931} | PROGRAMMING | 125878 | ||
| 4589 | 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 | |
| 680 | Frequency Mismatch (Easy Version) | binary search data structures divide and conquer hashing probabilities trees | Statement | F1 | Codeforces Round 940 (Div. 2) and CodeCraft-23 {1957} | PROGRAMMING | 2250.0 | Codeforces Round #940 and CodeCraft-23 (Div. 2) Editorial | 2600 |
| 630 | Frequency Mismatch (Hard Version) | binary search data structures dfs and similar hashing probabilities trees | Statement | F2 | Codeforces Round 940 (Div. 2) and CodeCraft-23 {1957} | PROGRAMMING | 1250.0 | Codeforces Round #940 and CodeCraft-23 (Div. 2) Editorial | 2700 |
| 5360 | 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 | |
| 13133 | Permutation of Rows and Columns | constructive algorithms data structures hashing math matrices sortings | Statement | E | Codeforces Round 950 (Div. 3) {1980} | PROGRAMMING | 130135 | ||
| 1459 | Permutation Problem (Hard Version) | brute force data structures hashing math number theory | Statement | G2 | Codeforces Round 954 (Div. 3) {1986} | PROGRAMMING | 130762 | ||
| 2299 | Penacony | brute force data structures dp hashing | Statement | G | Codeforces Round 962 (Div. 3) {1996} | PROGRAMMING | Codeforces Round 962 (Div. 3) Editorial | ||
| 5138 | DFS Checker (Easy Version) | constructive algorithms data structures dfs and similar hashing implementation | Statement | D1 | EPIC Institute of Technology Round August 2024 (Div. 1 + Div. 2) {2002} | PROGRAMMING | 1250.0 | EPIC Institute of Technology Round August 2024 (Div. 1 + Div. 2) Editorial | |
| 2900 | DFS Checker (Hard Version) | constructive algorithms data structures dfs and similar hashing implementation trees | Statement | D2 | EPIC Institute of Technology Round August 2024 (Div. 1 + Div. 2) {2002} | PROGRAMMING | 1250.0 | EPIC Institute of Technology Round August 2024 (Div. 1 + Div. 2) Editorial | |
| 5892 | Robin Hood Archery | data structures games greedy hashing | Statement | H | Codeforces Round 974 (Div. 3) {2014} | PROGRAMMING | Discussion stream (With Hints) | ||
| 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 | ||
| 273 | To the Infinity | data structures hashing math trees | Statement | F | Codeforces Round 1046 (Div. 1) {2135} | PROGRAMMING | 4000.0 | Codeforces Round 1046 (Div. 1, Div. 2) Editorial | |
| 599 | deCH OR Dations | data structures hashing | Statement | G | Good Bye 2025 {2178} | PROGRAMMING | 3500.0 |