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Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 1186 | Interestring graph and Apples | dfs and similar dsu graphs | Statement | E | Codeforces Beta Round 9 (Div. 2 Only) {9} | PROGRAMMING | Codeforces Beta Round #9 tutorial | 2300 | |
| 6586 | Hierarchy | dfs and similar dsu greedy shortest paths | Statement | B | Codeforces Beta Round 17 {17} | PROGRAMMING | Codeforces Beta Round #17 Tutorial | 1600 | |
| 2582 | Fairy | dfs and similar divide and conquer dsu | Statement | E | Codeforces Beta Round 19 {19} | PROGRAMMING | Code Force Beta Round 19 Solution | 2800 | |
| 3159 | Ring Road 2 | 2-sat dfs and similar dsu graphs | Statement | D | Codeforces Beta Round 27 (Codeforces format, Div. 2) {27} | PROGRAMMING | Solution of ABC @ Round#27 | 2300 | |
| 5662 | pSort | dfs and similar dsu graphs | Statement | B | Codeforces Beta Round 28 (Codeforces format) {28} | PROGRAMMING | Codeforces Beta Round #28 (Разбор задач A и B) | 1600 | |
| 5356 | Serial Time! | dfs and similar dsu | Statement | B | Codeforces Beta Round 56 {60} | PROGRAMMING | Solutions for Codeforces Beta Round #56 | 1500 | |
| 1439 | Chessboard Billiard | dfs and similar dsu graphs number theory | Statement | C | Codeforces Beta Round 68 {74} | PROGRAMMING | Solutions for Codeforces Beta Round #68 | 2100 | |
| 1189 | Beavermuncher-0xFF | dfs and similar dp dsu greedy trees | Statement | C | Codeforces Beta Round 69 (Div. 1 Only) {77} | PROGRAMMING | Codeforces Beta Round #69 tutorial | 2300 | |
| 430 | Pairs | dfs and similar dp dsu graphs implementation trees | Statement | E | Yandex.Algorithm Open 2011: Qualification 1 {81} | PROGRAMMING | 2600 | ||
| 1087 | Beautiful Road | dfs and similar dp dsu graphs implementation sortings trees | Statement | D | Codeforces Beta Round 73 (Div. 1 Only) {87} | PROGRAMMING | CodeForces Beta Round #73 div. 1 analysis (particulary with div. 2) | 2300 | |
| 448 | Leaders | dfs and similar dsu graphs trees | Statement | E | Yandex.Algorithm 2011: Finals {97} | PROGRAMMING | Финал Яндекс.Алгоритм: разбор A-B | 2800 | |
| 10976 | Cthulhu | dfs and similar dsu graphs | Statement | B | Codeforces Beta Round 80 (Div. 1 Only) {103} | PROGRAMMING | Tutorial | 1600 | |
| 3451 | Edges in MST | dfs and similar dsu graphs sortings | Statement | D | Codeforces Round 111 (Div. 2) {160} | PROGRAMMING | Codeforces Round #111 (Div. 2) Разбор Задач | 2500 | |
| 3064 | Party | brute force dfs and similar dsu graphs | Statement | C2 | ABBYY Cup 2.0 - Easy {177} | PROGRAMMING | 1500 | ||
| 3041 | Party | dfs and similar dsu graphs | Statement | C1 | ABBYY Cup 2.0 - Easy {177} | PROGRAMMING | 1500 | ||
| 1614 | Weak Memory | dfs and similar dsu | Statement | C | Codeforces Round 119 (Div. 1) {187} | PROGRAMMING | Tutorial | 2100 | |
| 24927 | Ice Skating | brute force dfs and similar dsu graphs | Statement | A | Codeforces Round 134 (Div. 1) {217} | PROGRAMMING | Editorial for Codeforces Round #134 | 1400 | |
| 2862 | The Road to Berland is Paved With Good Intentions | 2-sat dfs and similar dsu graphs | Statement | E | Codeforces Round 141 (Div. 2) {228} | PROGRAMMING | Codeforces Round #141 (Div. 2) Tutorial | 2000 | |
| 22035 | Learning Languages | dfs and similar dsu | Statement | A | Codeforces Round 170 (Div. 1) {277} | PROGRAMMING | Codeforces Round #170 Tutorial | 1500 | |
| 2813 | Connected Components | data structures dfs and similar dp dsu | Statement | D | Croc Champ 2013 - Round 1 {292} | PROGRAMMING | Чемпионат КРОК 2013 — Раунд 1 (Разбор задач) | 1900 | |
| 994 | The Red Button | combinatorics dfs and similar dsu graphs greedy | Statement | E | MemSQL start[c]up Round 1 {325} | PROGRAMMING | Editorial | 2700 | |
| 1109 | Fools and Foolproof Roads | data structures dfs and similar dsu graphs greedy | Statement | D | Codeforces Round 212 (Div. 2) {362} | PROGRAMMING | Codeforces Round #212 (Div. 2). Tutorial. Part 1. | 2500 | |
| 1761 | Dima and Trap Graph | binary search data structures dfs and similar dsu shortest paths two pointers | Statement | D | Codeforces Round 214 (Div. 2) {366} | PROGRAMMING | Codeforces Round #214 (Div. 2) — Tutorial | 2400 | |
| 15158 | DZY Loves Chemistry | dfs and similar dsu greedy | Statement | B | Codeforces Round 254 (Div. 2) {445} | PROGRAMMING | Codeforces Round #254 Editorial | 1500 | |
| 6598 | Civilization | dfs and similar dp dsu ternary search trees | Statement | C | Codeforces Round 260 (Div. 1) {455} | PROGRAMMING | Codeforces Round #260 — Editorial | 2200 | |
| 2684 | Information Graph | dfs and similar dsu graphs trees | Statement | E | Codeforces Round 266 (Div. 2) {466} | PROGRAMMING | Editorial Codeforces Round #266 (Div. 2) | 2400 | |
| 5443 | Two Sets | 2-sat dfs and similar dsu graph matchings greedy | Statement | B | Codeforces Round 268 (Div. 1) {468} | PROGRAMMING | 13896 | 2000 | |
| 6683 | Design Tutorial: Inverse the Problem | dfs and similar dsu shortest paths trees | Statement | D | Codeforces Round 270 {472} | PROGRAMMING | Editorial | 1900 | |
| 9689 | New Year Permutation | dfs and similar dsu graphs greedy math sortings | Statement | B | Good Bye 2014 {500} | PROGRAMMING | Tutorial 2 | 1600 | |
| 15133 | Mr. Kitayuta's Colorful Graph | dfs and similar dp dsu graphs | Statement | B | Codeforces Round 286 (Div. 2) {505} | PROGRAMMING | Tutorial | 1500 | |
| 2585 | Mr. Kitayuta's Colorful Graph | brute force dfs and similar dsu graphs | Statement | D | Codeforces Round 286 (Div. 1) {506} | PROGRAMMING | Editorial | 2300 | |
| 1557 | Drazil and Morning Exercise | dfs and similar dp dsu trees two pointers | Statement | D | Codeforces Round 292 (Div. 1) {516} | PROGRAMMING | 16468 | 2800 | |
| 1987 | Love Triangles | dfs and similar dsu graphs | Statement | C | Codeforces Round 309 (Div. 1) {553} | PROGRAMMING | Codeforces Round #309 Editorial | 2300 | |
| 19041 | Lomsat gelral | data structures dfs and similar dsu trees | Statement | E | Educational Codeforces Round 2 {600} | PROGRAMMING | Editorial | 2300 | |
| 1260 | 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 | |
| 2718 | Moodular Arithmetic | combinatorics dfs and similar dsu math number theory | Statement | B | Codeforces Round 334 (Div. 1) {603} | PROGRAMMING | Codeforces Round #334 Editorial | 2000 | |
| 10659 | Minimum spanning tree for each edge | data structures dfs and similar dsu graphs trees | Statement | E | Educational Codeforces Round 3 {609} | PROGRAMMING | Editorial | 2100 | |
| 271 | Island Puzzle | dfs and similar dsu graphs trees | Statement | F | 8VC Venture Cup 2016 - Final Round {627} | PROGRAMMING | 8VC Venture Cup 2016 — Final Round Editorial | 3400 | |
| 2228 | Table Compression | dfs and similar dp dsu graphs greedy | Statement | C | Codeforces Round 345 (Div. 1) {650} | PROGRAMMING | Codeforces Round #345: editorial | 2300 | |
| 1037 | Clockwork Bomb | data structures dfs and similar dsu greedy trees | Statement | E | Codeforces Round 345 (Div. 1) {650} | PROGRAMMING | Codeforces Round #345: editorial | 3100 | |
| 2973 | Pursuit For Artifacts | dfs and similar dsu graphs trees | Statement | E | Educational Codeforces Round 10 {652} | PROGRAMMING | Editorial of Educational Codeforces Round 10 | 2300 | |
| 1763 | Bear and Forgotten Tree 2 | dfs and similar dsu graphs trees | Statement | E | IndiaHacks 2016 - Online Edition (Div. 1 + Div. 2) {653} | PROGRAMMING | IndiaHacks Finals 2016 — Editorial | 2400 | |
| 8068 | New Reform | data structures dfs and similar dsu graphs greedy | Statement | E | Codeforces Round 346 (Div. 2) {659} | PROGRAMMING | Editorial for Codeforces Round #346 (Div. 2) | 1600 | |
| 1992 | Polycarp and Hay | dfs and similar dsu graphs greedy sortings | Statement | F | Codeforces Round 346 (Div. 2) {659} | PROGRAMMING | Editorial for Codeforces Round #346 (Div. 2) | 2100 | |
| 1285 | Bear and Square Grid | dfs and similar dsu implementation | Statement | C | Codeforces Round 356 (Div. 1) {679} | PROGRAMMING | Codeforces Round #356 — Editorial | 2500 | |
| 6660 | Swaps in Permutation | dfs and similar dsu math | Statement | D | Educational Codeforces Round 14 {691} | PROGRAMMING | Editorial of Educational Codeforces Round 14 | 1700 | |
| 6245 | Fix a Tree | constructive algorithms dfs and similar dsu graphs trees | Statement | B | Codeforces Round 363 (Div. 1) {698} | PROGRAMMING | 46148 | 1700 | |
| 2696 | Digit Tree | dfs and similar divide and conquer dsu trees | Statement | C | Codeforces Round 372 (Div. 1) {715} | PROGRAMMING | Codeforces Round #372 Editorial | 2800 | |
| 7575 | Lakes in Berland | dfs and similar dsu graphs greedy implementation | Statement | D | Codeforces Round 375 (Div. 2) {723} | PROGRAMMING | 1600 | ||
| 7962 | Socks | dfs and similar dsu graphs greedy | Statement | C | Codeforces Round 376 (Div. 2) {731} | PROGRAMMING | 47840 | 1600 | |
| 5976 | Arpa's weak amphitheater and Mehrdad's valuable Hoses | dfs and similar dp dsu | Statement | B | Codeforces Round 383 (Div. 1) {741} | PROGRAMMING | Codeforces Round #383 editorial | 1700 | |
| 258 | New Year and Snowy Grid | dfs and similar dsu graphs interactive | Statement | H | Good Bye 2016 {750} | PROGRAMMING | Good Bye 2016 — hints and codes | 3400 | |
| 15341 | PolandBall and Forest | dfs and similar dsu graphs interactive trees | Statement | C | 8VC Venture Cup 2017 - Elimination Round {755} | PROGRAMMING | 8VC Venture Cup 2017 — Elimination Round [Editorial] | 1300 | |
| 12084 | Timofey and a tree | dfs and similar dp dsu graphs implementation trees | Statement | A | Codeforces Round 395 (Div. 1) {763} | PROGRAMMING | Codeforces Round #395 [Editorial] | 1600 | |
| 3994 | Mahmoud and a Dictionary | data structures dfs and similar dp dsu graphs | Statement | D | Codeforces Round 396 (Div. 2) {766} | PROGRAMMING | Codeforces round #396 editorial | 2000 | |
| 17995 | Bear and Friendship Condition | dfs and similar dsu graphs | Statement | A | VK Cup 2017 - Round 1 {771} | PROGRAMMING | VK Cup 2017 Round 1 and CF Round 405 — Editorial | 1500 | |
| 6421 | The Door Problem | 2-sat dfs and similar dsu graphs | Statement | D | ICM Technex 2017 and Codeforces Round 400 (Div. 1 + Div. 2, combined) {776} | PROGRAMMING | ICM Technex 2017 and Codeforces Round #400 (Div. 1 + Div. 2, combined) Editorial | 2000 | |
| 1011 | Peterson Polyglot | brute force dfs and similar dsu hashing strings trees | Statement | C | Codeforces Round 402 (Div. 1) {778} | PROGRAMMING | Codeforces Round #402, Editorial | 2600 | |
| 2936 | Weird journey | combinatorics constructive algorithms dfs and similar dsu graphs | Statement | B | Codeforces Round 407 (Div. 1) {788} | PROGRAMMING | Codeforces Round #407(Div.1 + Div.2) Editorial | 2200 | |
| 6001 | Sorting by Subsequences | dfs and similar dsu implementation math sortings | Statement | A | AIM Tech Round 4 (Div. 1) {843} | PROGRAMMING | AIM Tech Round 4 -- Editorial | 1400 | |
| 2146 | Desk Disorder | combinatorics dfs and similar dsu graphs trees | Statement | E | MemSQL Start[c]UP 3.0 - Round 1 {859} | PROGRAMMING | Tutorial | 2100 | |
| 1333 | Points, Lines and Ready-made Titles | dfs and similar dsu graphs trees | Statement | E | Technocup 2018 - Elimination Round 2 {870} | PROGRAMMING | Editorial Codeforces Round 440 Div.1+Div.2 (and Technocup 2018 — Elimination Round 2) | 2400 | |
| 1329 | Bipartite Segments | binary search data structures dfs and similar dsu graphs two pointers | Statement | C | Codeforces Round 453 (Div. 1) {901} | PROGRAMMING | Codeforces Round #453 (Div. 1 & Div. 2) Editorial | 2500 | |
| 12049 | Coloring a Tree | dfs and similar dsu greedy | Statement | B | Codeforces Round 453 (Div. 2) {902} | PROGRAMMING | Codeforces Round #453 (Div. 1 & Div. 2) Editorial | 1300 | |
| 7949 | Connected Components? | data structures dfs and similar dsu graphs | Statement | E | Educational Codeforces Round 37 (Rated for Div. 2) {920} | PROGRAMMING | T | 2100 | |
| 261 | Iqea | data structures dfs and similar divide and conquer dsu shortest paths trees | Statement | E | Codeforces Round 467 (Div. 1) {936} | PROGRAMMING | Codeforces Round #467, Editorial | 3300 | |
| 8286 | Love Rescue | dfs and similar dsu graphs greedy strings | Statement | D | Codeforces Round 464 (Div. 2) {939} | PROGRAMMING | Analysis of Codeforces Round #464 | 1600 | |
| 26414 | Cyclic Components | dfs and similar dsu graphs | Statement | E | Codeforces Round 479 (Div. 3) {977} | PROGRAMMING | Codeforces Round #479 (Div. 3) Editorial | 1500 | |
| 2773 | AND Graph | bitmasks dfs and similar dsu graphs | Statement | C | Codeforces Round 485 (Div. 1) {986} | PROGRAMMING | Codeforces Round #485 Editorial | 2300 | |
| 4418 | Chemical table | constructive algorithms dfs and similar dsu graphs matrices | Statement | B | Codeforces Round 500 (Div. 1) [based on EJOI] {1012} | PROGRAMMING | 60920 | 1900 | |
| 1058 | Mobile Phone Network | dfs and similar dsu graphs trees | Statement | F | Codeforces Round 504 (rated, Div. 1 + Div. 2, based on VK Cup 2018 Final) {1023} | PROGRAMMING | Codeforces Round 504 Editorial | 2600 | |
| 1994 | Session in BSU | binary search dfs and similar dsu graph matchings graphs | Statement | F | Educational Codeforces Round 49 (Rated for Div. 2) {1027} | PROGRAMMING | Educational Codeforces Round 49 Editorial | 2400 | |
| 1522 | Network Safety | dfs and similar dsu graphs math sortings | Statement | C | Codeforces Round 507 (Div. 1, based on Olympiad of Metropolises) {1039} | PROGRAMMING | 61668 | 2300 | |
| 1588 | Leaf Sets | data structures dfs and similar dsu graphs greedy sortings trees | Statement | F | Codeforces Round 510 (Div. 2) {1042} | PROGRAMMING | Tutorial | 2400 | |
| 1796 | Power Tree | dfs and similar dp dsu graphs greedy trees | Statement | D | Codeforces Round 543 (Div. 1, based on Technocup 2019 Final Round) {1120} | PROGRAMMING | Разбор задач финала Технокубка 2019 и Codeforces Round #543 | 2400 | |
| 9519 | Connect | brute force dfs and similar dsu | Statement | C | Codeforces Round 542 [Alex Lopashev Thanks-Round] (Div. 2) {1130} | PROGRAMMING | 65520 | 1400 | |
| 3675 | Gourmet choice | dfs and similar dp dsu graphs greedy | Statement | D | Codeforces Round 541 (Div. 2) {1131} | PROGRAMMING | Codeforces Round #541 Editorial | 2000 | |
| 3872 | Spanning Tree with One Fixed Degree | constructive algorithms dfs and similar dsu graphs greedy | Statement | F2 | Codeforces Round 544 (Div. 3) {1133} | PROGRAMMING | Codeforces Round #544 (Div. 3) Editorial | 2200 | |
| 17308 | Edgy Trees | dfs and similar dsu graphs math trees | Statement | C | Codeforces Round 548 (Div. 2) {1139} | PROGRAMMING | Codeforces Round #548 Editorial | 1500 | |
| 4865 | 0-1-Tree | dfs and similar divide and conquer dp dsu trees | Statement | D | Educational Codeforces Round 64 (Rated for Div. 2) {1156} | PROGRAMMING | 66827 | 2300 | |
| 27170 | News Distribution | dfs and similar dsu graphs | Statement | C | Educational Codeforces Round 65 (Rated for Div. 2) {1167} | PROGRAMMING | 67058 | 1400 | |
| 13904 | Cover it! | dfs and similar dsu graphs shortest paths trees | Statement | E | Codeforces Round 565 (Div. 3) {1176} | PROGRAMMING | 67598 | 1700 | |
| 10876 | Cow and Snacks | dfs and similar dsu graphs | Statement | D | Codeforces Round 584 - Dasha Code Championship - Elimination Round (rated, open for everyone, Div. 1 + Div. 2) {1209} | PROGRAMMING | 69791 | 1700 | |
| 3087 | 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 | |
| 3045 | Tourism | dfs and similar dp dsu graphs greedy trees | Statement | E | Codeforces Round 586 (Div. 1 + Div. 2) {1220} | PROGRAMMING | Codeforces Round #586 Editorial | 2200 | |
| 9557 | 0-1 MST | dfs and similar dsu graphs sortings | Statement | B | Codeforces Round 599 (Div. 1) {1242} | PROGRAMMING | Codeforces Round #599 Editorial | 1900 | |
| 18584 | Books Exchange (hard version) | dfs and similar dsu math | Statement | B2 | Codeforces Round 595 (Div. 3) {1249} | PROGRAMMING | Codeforces Round #595 (Div. 3) Editorial | 1300 | |
| 10365 | Harmonious Graph | constructive algorithms dfs and similar dsu graphs greedy sortings | Statement | D | Codeforces Round 600 (Div. 2) {1253} | PROGRAMMING | Editorial | 1700 | |
| 422 | Send Tree to Charlie | combinatorics dfs and similar dsu trees | Statement | E | Codeforces Round 601 (Div. 1) {1254} | PROGRAMMING | Codeforces Round #601 Editorial | 3200 | |
| 16548 | Secret Passwords | dfs and similar dsu graphs | Statement | D | Codeforces Round 603 (Div. 2) {1263} | PROGRAMMING | Codeforces Round #603 (Div. 2) Editorial | 1500 | |
| 5731 | Two Fairs | combinatorics dfs and similar dsu graphs | Statement | B | Codeforces Round 606 (Div. 1, based on Technocup 2020 Elimination Round 4) {1276} | PROGRAMMING | Technocup 2020 — Elimination Round 4 + Codeforces Round 606: Editorial | 1900 | |
| 2088 | Prefix Enlightenment | dfs and similar dsu graphs | Statement | C | Codeforces Round 616 (Div. 1) {1290} | PROGRAMMING | 1750.0 | Codeforces Round #616 Editorial | 2400 |
| 690 | Cow and Vacation | dfs and similar dsu trees | Statement | F | Codeforces Round 621 (Div. 1 + Div. 2) {1307} | PROGRAMMING | 3000.0 | Codeforces Round #621 (Div. 1 + Div. 2) Editorial | 3200 |
| 21583 | K-Complete Word | dfs and similar dsu greedy implementation strings | Statement | C | Codeforces Round 630 (Div. 2) {1332} | PROGRAMMING | 1250.0 | Codeforces Round #630 Editorial | 1500 |
| 2442 | Robots on a Grid | data structures dfs and similar dsu graphs greedy matrices | Statement | F | Codeforces Round 634 (Div. 3) {1335} | PROGRAMMING | 75993 | 2600 | |
| 6394 | Monopole Magnets | constructive algorithms dfs and similar dsu graphs | Statement | B | Codeforces Round 639 (Div. 1) {1344} | PROGRAMMING | 1000.0 | Codeforces Round #639 Editorial | 2000 |
| 2127 | Johnny and Megan's Necklace | binary search bitmasks constructive algorithms dfs and similar dsu graphs | Statement | C | Codeforces Round 647 (Div. 1) - Thanks, Algo Muse! {1361} | PROGRAMMING | 2000.0 | Codeforces Round #647 Editorial | 2500 |
| 7582 | Tree Shuffling | dfs and similar dp dsu greedy trees | Statement | E | Codeforces Round 646 (Div. 2) {1363} | PROGRAMMING | 2250.0 | 78202 | 2000 |
| 21257 | Solve The Maze | constructive algorithms dfs and similar dsu graphs greedy implementation shortest paths | Statement | D | Codeforces Round 648 (Div. 2) {1365} | PROGRAMMING | 1500.0 | Editorial — Codeforces Round #648 | 1700 |
| 1877 | Columns Swaps | 2-sat dfs and similar dsu graphs implementation | Statement | G | Codeforces Round 656 (Div. 3) {1385} | PROGRAMMING | Codeforces Round #656 (Div. 3) Editorial | 2300 | |
| 8658 | Peaceful Rooks | dfs and similar dsu graphs | Statement | C | Technocup 2021 - Elimination Round 3 {1411} | PROGRAMMING | 1750.0 | Technocup 2021 Elimination Round 3 and Round #692 (Div. 1 + Div. 2) Editorial | |
| 2819 | Graph and Queries | data structures dfs and similar dsu graphs trees | Statement | D | Codeforces Round 673 (Div. 1) {1416} | PROGRAMMING | 2000.0 | Codeforces Round #673 Editorial | 2600 |
| 619 | Rain of Fire | binary search dfs and similar dsu graphs implementation sortings | Statement | F | Codeforces Round 671 (Div. 2) {1419} | PROGRAMMING | 3000.0 | Codeforces Round #671 Editorial | |
| 1917 | Team-Building | 2-sat dfs and similar dsu graphs | Statement | C | Codeforces Round 680 (Div. 1, based on Moscow Team Olympiad) {1444} | PROGRAMMING | 1500.0 | Codeforces Round #680 Editorial | |
| 6779 | Number of Simple Paths | combinatorics data structures dfs and similar dsu graphs trees | Statement | E | Codeforces Round 686 (Div. 3) {1454} | PROGRAMMING | Codeforces Round #686 (Div. 3) Editorial | ||
| 1773 | Plan of Lectures | dfs and similar dsu graphs | Statement | E | Educational Codeforces Round 100 (Rated for Div. 2) {1463} | PROGRAMMING | Educational Codeforces Round 100 Editorial | ||
| 3079 | Euclid's nightmare | dfs and similar dsu graphs math | Statement | F | Good Bye 2020 {1466} | PROGRAMMING | 1750.0 | Good Bye 2020 Editorial | |
| 4235 | Strange Housing | constructive algorithms dfs and similar dsu graph matchings graphs | Statement | D | Codeforces Round 694 (Div. 1) {1470} | PROGRAMMING | 1500.0 | 86464 | |
| 9282 | Journey | dfs and similar dp dsu implementation two pointers | Statement | D | Educational Codeforces Round 103 (Rated for Div. 2) {1476} | PROGRAMMING | 87356 | ||
| 1770 | Complete the MST | data structures dfs and similar dsu graphs greedy math | Statement | C | Codeforces Round 715 (Div. 1) {1508} | PROGRAMMING | 1500.0 | Codeforces Round #715 Editorial | |
| 2141 | Phoenix and Earthquake | constructive algorithms dfs and similar dsu graphs greedy trees | Statement | F | Codeforces Global Round 14 {1515} | PROGRAMMING | 3250.0 | Editorial | |
| 13979 | Little Alawn's Puzzle | combinatorics dfs and similar dp dsu graphs math | Statement | C | Codeforces LATOKEN Round 1 (Div. 1 + Div. 2) {1534} | PROGRAMMING | 1250.0 | Codeforces LATOKEN Round 1 (Div. 1 + Div. 2) Editorial | |
| 2846 | Figure Fixing | constructive algorithms dfs and similar dsu graphs math | Statement | F | Codeforces Round 726 (Div. 2) {1537} | PROGRAMMING | 2000.0 | Codeforces Round #726 (Div.2) Editorial | |
| 3186 | Mocha and Diana (Hard Version) | brute force constructive algorithms dfs and similar dsu graphs greedy trees two pointers | Statement | D2 | Codeforces Round 738 (Div. 2) {1559} | PROGRAMMING | 1500.0 | Tutorial (en) | 2500 |
| 9752 | The Number of Imposters | constructive algorithms dfs and similar dp dsu graphs | Statement | D | Codeforces Round 747 (Div. 2) {1594} | PROGRAMMING | 1750.0 | 95525 | 1700 |
| 2792 | Unusual Minesweeper | binary search dfs and similar dsu implementation sortings | Statement | G | Codeforces Round 762 (Div. 3) {1619} | PROGRAMMING | Tutorial | ||
| 7844 | MinOr Tree | bitmasks dfs and similar dsu greedy | Statement | G | Codeforces Round 764 (Div. 3) {1624} | PROGRAMMING | Codeforces Round #764 (Div. 3) Editorial | ||
| 2835 | Cars | constructive algorithms dfs and similar dsu graphs greedy sortings | Statement | E | Codeforces Round 772 (Div. 2) {1635} | PROGRAMMING | 2250.0 | Codeforces Round #772 Editorial | |
| 588 | Air Reform | data structures dfs and similar divide and conquer dsu graphs implementation trees | Statement | E | Codeforces Round 775 (Div. 1, based on Moscow Open Olympiad in Informatics) {1648} | PROGRAMMING | 2500.0 | Codeforces Round #775 Editorial | |
| 2011 | 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 | |
| 1148 | Narrow Components | data structures dfs and similar dsu trees | Statement | E | Educational Codeforces Round 126 (Rated for Div. 2) {1661} | PROGRAMMING | Educational Codeforces Round 126 Editorial | ||
| 11119 | Where is the Pizza? | data structures dfs and similar dsu graphs implementation math | Statement | C | Codeforces Round 788 (Div. 2) {1670} | PROGRAMMING | 1750.0 | Tutorial | 1400 |
| 4134 | Tokitsukaze and Two Colorful Tapes | constructive algorithms dfs and similar dsu graphs greedy | Statement | C | Codeforces Round 789 (Div. 1) {1677} | PROGRAMMING | 1250.0 | Tutorial | |
| 965 | Lenient Vertex Cover | data structures dfs and similar divide and conquer dsu graphs | Statement | F | Educational Codeforces Round 128 (Rated for Div. 2) {1680} | PROGRAMMING | 102852 | ||
| 2423 | Unique Occurrences | data structures dfs and similar divide and conquer dp dsu trees | Statement | F | Educational Codeforces Round 129 (Rated for Div. 2) {1681} | PROGRAMMING | 103163 | 2300 | |
| 532 | Permutation Weight (Easy Version) | constructive algorithms dfs and similar dsu | Statement | D1 | Codeforces Round 794 (Div. 1) {1685} | PROGRAMMING | 1500.0 | 103198 | 2800 |
| 1716 | Sanae and Giant Robot | brute force constructive algorithms data structures dfs and similar dsu | Statement | C | Codeforces Round 796 (Div. 1) {1687} | PROGRAMMING | 1500.0 | Editorial of Codeforces Round 796 | |
| 1404 | 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) | |
| 2143 | Number of Groups | data structures dfs and similar dsu graphs greedy sortings | Statement | E | CodeCraft-22 and Codeforces Round 795 (Div. 2) {1691} | PROGRAMMING | 2250.0 | Editorial for CodeCraft-22 and Codeforces Round #795 (Div. 2) | |
| 1165 | 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 | |
| 1476 | Coloring | brute force combinatorics constructive algorithms dfs and similar dp dsu graphs implementation | Statement | E | Educational Codeforces Round 130 (Rated for Div. 2) {1697} | PROGRAMMING | 103835 | ||
| 18590 | Split Into Two Sets | dfs and similar dsu graph matchings graphs | Statement | E | Codeforces Round 805 (Div. 3) {1702} | PROGRAMMING | 104763 | ||
| 1961 | DFS Trees | data structures dfs and similar dsu graphs greedy trees | Statement | C | Codeforces Round 808 (Div. 1) {1707} | PROGRAMMING | 1250.0 | 104930 | |
| 4147 | XOR Tree | data structures dfs and similar dsu greedy trees | Statement | E | Educational Codeforces Round 132 (Rated for Div. 2) {1709} | PROGRAMMING | 105164 | ||
| 11033 | Phase Shift | dfs and similar dsu graphs greedy strings | Statement | C | Codeforces Round 824 (Div. 2) {1735} | PROGRAMMING | 1250.0 | Codeforces Round #824 — editorial | |
| 3779 | Permutation Addicts | constructive algorithms dfs and similar dsu graphs trees | Statement | D | Codeforces Global Round 22 {1738} | PROGRAMMING | 2000.0 | Editorial of Codeforces Global Round <strong>22</strong> | |
| 1053 | Tick, Tock | 2-sat combinatorics dfs and similar dsu graphs | Statement | E | Codeforces Round 836 (Div. 2) {1758} | PROGRAMMING | 2250.0 | Codeforces Round #836 (Div. 2) Editorial | |
| 1238 | Doremy's Experimental Tree | brute force constructive algorithms dfs and similar dsu sortings trees | Statement | F | Codeforces Global Round 24 {1764} | PROGRAMMING | 2250.0 | Codeforces Global Round 24 Editorial | |
| 9237 | Lucky Permutation | dfs and similar dsu graphs greedy | Statement | D | Codeforces Round 842 (Div. 2) {1768} | PROGRAMMING | 1750.0 | Codeforces Round #842 (Div. 2) Editorial | |
| 4444 | Koxia and Game | data structures dfs and similar dsu games graph matchings graphs implementation | Statement | D | Good Bye 2022: 2023 is NEAR {1770} | PROGRAMMING | 1500.0 | Good Bye 2022 -- Editorial | |
| 2430 | Edge Reverse | binary search dfs and similar dsu graphs | Statement | E | Codeforces Round 845 (Div. 2) and ByteRace 2023 {1777} | PROGRAMMING | 2250.0 | Codeforces Round #845 (Div. 2) and ByteRace 2023 Editorial | |
| 1210 | XOR, Tree, and Queries | constructive algorithms dfs and similar dsu graphs trees | Statement | F | Codeforces Round 851 (Div. 2) {1788} | PROGRAMMING | 3000.0 | Codeforces Round #851 (Div. 2) Editorial | |
| 638 | Li Hua and Path | data structures dfs and similar divide and conquer dsu trees | Statement | F | Codeforces Round 864 (Div. 2) {1797} | PROGRAMMING | 3000.0 | Codeforces Round 864 (Div. 2) Editorial | |
| 1948 | There Should Be a Lot of Maximums | data structures dfs and similar dsu graphs trees | Statement | E | Codeforces Round 862 (Div. 2) {1805} | PROGRAMMING | 2250.0 | Editorial of Codeforces Round #862 (Div. 2) | |
| 9505 | A Wide, Wide Graph | dfs and similar dp dsu greedy trees | Statement | D | Codeforces Round 862 (Div. 2) {1805} | PROGRAMMING | 1750.0 | Editorial of Codeforces Round #862 (Div. 2) | |
| 3977 | 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!) | |
| 2225 | Is It Flower? | dfs and similar dsu graphs implementation | Statement | F | Codeforces Round 863 (Div. 3) {1811} | PROGRAMMING | 114788 | ||
| 1717 | LuoTianyi and XOR-Tree | data structures dfs and similar dp dsu greedy trees | Statement | C | Codeforces Round 872 (Div. 1) {1824} | PROGRAMMING | 1750.0 | CodeForces Round 872(Div. 1&2) Editorial | 2500 |
| 27582 | The Lakes | dfs and similar dsu graphs implementation | Statement | E | Codeforces Round 871 (Div. 4) {1829} | PROGRAMMING | Codeforces Round 871 (Div. 4) Editorial | 1100 | |
| 6492 | Ksyusha and Chinchilla | dfs and similar dp dsu greedy implementation trees | Statement | G | Codeforces Round 874 (Div. 3) {1833} | PROGRAMMING | 116636 | ||
| 2189 | Great Grids | constructive algorithms dfs and similar dsu graphs math | Statement | E | Codeforces Round 884 (Div. 1 + Div. 2) {1844} | PROGRAMMING | 2000.0 | Codeforces Round #884 (Div. 1 + Div. 2) Editorial | |
| 7647 | Selling a Menagerie | dfs and similar dsu graphs implementation math | Statement | F | Codeforces Round 895 (Div. 3) {1872} | PROGRAMMING | Codeforces Round 895 (Div. 3) Editorial | ||
| 9713 | Mad City | dfs and similar dsu graphs shortest paths | Statement | H | Codeforces Round 898 (Div. 4) {1873} | PROGRAMMING | 120634 | ||
| 1082 | Lexichromatography | combinatorics dfs and similar dsu graphs two pointers | Statement | D | Codeforces Round 902 (Div. 1, based on COMPFEST 15 - Final Round) {1876} | PROGRAMMING | 1750.0 | Codeforces Round #902 (Div. 1, Div. 2, based on COMPFEST 15 — Final Round) Editorial | |
| 4089 | Unusual Entertainment | data structures dfs and similar dsu shortest paths sortings trees | Statement | G | Codeforces Round 909 (Div. 3) {1899} | PROGRAMMING | Разбор Codeforces Round 909 (Div. 3) | ||
| 2460 | Light Bulbs (Easy Version) | brute force combinatorics dfs and similar dp dsu graphs math | Statement | G1 | Codeforces Round 916 (Div. 3) {1914} | PROGRAMMING | Codeforces Round 916 (Div. 3) Editorial | ||
| 1879 | 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 | ||
| 1280 | Smooth Sailing (Easy Version) | binary search data structures dfs and similar dsu graphs | Statement | F1 | Codeforces Round 919 (Div. 2) {1920} | PROGRAMMING | 2500.0 | Editorial for Codeforces Round #919 (Div. 2) | |
| 5308 | Count Paths | data structures dfs and similar divide and conquer dp dsu trees | Statement | E | Educational Codeforces Round 162 (Rated for Div. 2) {1923} | PROGRAMMING | Educational Codeforces Round 162 Editorial | ||
| 5508 | Microcycle | data structures dfs and similar dsu graphs greedy trees | Statement | F | Codeforces Round 923 (Div. 3) {1927} | PROGRAMMING | 125597 | ||
| 106 | Parallel Universes | *special constructive algorithms dfs and similar dsu graphs | Statement | A | XVIII Open Olympiad in Informatics - Final Stage, Day 2 (Unrated, Online Mirror, IOI rules) {1940} | PROGRAMMING | |||
| 44 | Burenka and Pether | *special data structures dfs and similar divide and conquer dsu graphs sortings trees | Statement | C | XVIII Open Olympiad in Informatics - Final Stage, Day 2 (Unrated, Online Mirror, IOI rules) {1940} | PROGRAMMING | |||
| 7397 | Maximize the Largest Component (Easy Version) | brute force data structures dfs and similar dsu graphs implementation | Statement | H1 | Codeforces Round 952 (Div. 4) {1985} | PROGRAMMING | Codeforces Round 952 (Div. 4) Editorial | ||
| 1957 | Maximize the Largest Component (Hard Version) | data structures dfs and similar dsu implementation | Statement | H2 | Codeforces Round 952 (Div. 4) {1985} | PROGRAMMING | Codeforces Round 952 (Div. 4) Editorial | ||
| 6694 | Non-academic Problem | combinatorics dfs and similar dsu graphs | Statement | F | Codeforces Round 954 (Div. 3) {1986} | PROGRAMMING | 130762 | ||
| 4427 | Iris and the Tree | brute force data structures dfs and similar dsu math trees | Statement | B | Codeforces Round 969 (Div. 1) {2006} | PROGRAMMING | 1250.0 | Tutorial | |
| 7562 | Connect the Dots | brute force dfs and similar dp dsu graphs math trees | Statement | D | Codeforces Round 976 (Div. 2) and Divide By Zero 9.0 {2020} | PROGRAMMING | 1500.0 | Tutorial for Codeforces Round 976 (Div. 2) and Divide By Zero 9.0 | |
| 778 | Billetes MX (Easy Version) | 2-sat binary search combinatorics dfs and similar dsu graphs | Statement | E1 | Codeforces Round 978 (Div. 2) {2022} | PROGRAMMING | 2250.0 | Codeforces Round 978 (Div 2) Editorial | |
| 728 | Billetes MX (Hard Version) | binary search combinatorics dfs and similar dsu graphs | Statement | E2 | Codeforces Round 978 (Div. 2) {2022} | PROGRAMMING | 1000.0 | Codeforces Round 978 (Div 2) Editorial | |
| 4003 | Cool Graph | constructive algorithms data structures dfs and similar dsu graphs trees | Statement | D | Refact.ai Match 1 (Codeforces Round 985) {2029} | PROGRAMMING | 2250.0 | Refact.ai Match 1 (Codeforces Round 985) Editorial | |
| 10044 | Penchick and Desert Rabbit | data structures dfs and similar dp dsu greedy two pointers | Statement | D | Codeforces Round 987 (Div. 2) {2031} | PROGRAMMING | 2000.0 | Codeforces Round 987 (Div. 2) Editorial | |
| 14460 | Sakurako, Kosuke, and the Permutation | brute force data structures dfs and similar dsu fft greedy math | Statement | E | Codeforces Round 981 (Div. 3) {2033} | PROGRAMMING | 135520 | ||
| 3965 | Medium Demon Problem (hard version) | dfs and similar dp dsu graphs implementation trees | Statement | G2 | Codeforces Round 993 (Div. 4) {2044} | PROGRAMMING | Codeforces Round 993 (Div. 4) Editorial | ||
| 12630 | Graph Composition | dfs and similar dsu graphs greedy | Statement | E | Codeforces Round 998 (Div. 3) {2060} | PROGRAMMING | Codeforces Round 998 (Div. 3) Editorial | ||
| 1574 | Counting Is Not Fun (Easy Version) | combinatorics data structures dfs and similar dsu implementation math | Statement | F1 | Codeforces Round 1000 (Div. 2) {2063} | PROGRAMMING | 1750.0 | Codeforces Round 1000 (Div. 2) — Editorial | |
| 943 | Counting Is Not Fun (Hard Version) | combinatorics data structures dfs and similar dsu trees | Statement | F2 | Codeforces Round 1000 (Div. 2) {2063} | PROGRAMMING | 1500.0 | Codeforces Round 1000 (Div. 2) — Editorial | |
| 2411 | Triangle Tree | data structures dfs and similar dp dsu greedy trees | Statement | E | Codeforces Round 1000 (Div. 2) {2063} | PROGRAMMING | 2750.0 | Codeforces Round 1000 (Div. 2) — Editorial | |
| 380 | Porto Vs. Benfica | data structures dfs and similar dsu graphs shortest paths | Statement | E | European Championship 2025 - Online Mirror (Unrated, ICPC Rules, Teams Preferred) {2068} | PROGRAMMING | 140239 | ||
| 16454 | Disappearing Permutation | dfs and similar dsu graphs greedy implementation | Statement | C | Educational Codeforces Round 177 (Rated for Div. 2) {2086} | PROGRAMMING | Educational Codeforces Round 177 Editorial | ||
| 2562 | Red Light, Green Light (Hard version) | binary search dfs and similar dp dsu graphs implementation number theory | Statement | D2 | Codeforces Round 1030 (Div. 2) {2118} | PROGRAMMING | 1000.0 | Codeforces Round 1030 (Div. 2) Editorial | |
| 4017 | Ancient Tree | constructive algorithms data structures dfs and similar dsu greedy trees | Statement | E | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) {2127} | PROGRAMMING | 2500.0 | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) Editorial | |
| 4933 | By the Assignment | bitmasks dfs and similar dsu graphs | Statement | C | Codeforces Round 1046 (Div. 1) {2135} | PROGRAMMING | 1750.0 | Codeforces Round 1046 (Div. 1, Div. 2) Editorial | |
| 85 | Merging Vertices in a Graph | *special dfs and similar dsu graphs | Statement | H | Kotlin Heroes: Episode 13 {2141} | PROGRAMMING | Kotlin Heroes 13 Editorial | ||
| 743 | Juan's Colorful Tree | data structures data structures dfs and similar dfs and similar dsu graphs graphs trees | Statement | F | Codeforces Round 1056 (Div. 2) {2155} | PROGRAMMING | 3000.0 | Codeforces Round 1056 (Div. 2) Editorial | |
| 3135 | Journey | dfs and similar dsu graphs greedy | Statement | E | Codeforces Global Round 30 (Div. 1 + Div. 2) {2164} | PROGRAMMING | 2250.0 | Codeforces Global Round 30 Editorial | |
| 1867 | Conquer or of Forest | combinatorics dfs and similar dsu trees | Statement | F | Good Bye 2025 {2178} | PROGRAMMING | 2750.0 | ||
| 4709 | Tree Orientation (Easy Version) | constructive algorithms dfs and similar dsu graphs greedy trees | Statement | D1 | Codeforces Round 1086 (Div. 2) {2208} | PROGRAMMING | 1250.0 | Tutorial | |
| 2053 | Tree Orientation (Hard Version) | data structures dfs and similar dsu graphs greedy matrices sortings trees | Statement | D2 | Codeforces Round 1086 (Div. 2) {2208} | PROGRAMMING | 1250.0 | Tutorial | |
| 2201 | Vessels, Heights and Two Versions (Hard Version) | data structures dfs and similar dsu greedy implementation trees | Statement | F | Codeforces Round 1102 (Div. 2) {2234} | PROGRAMMING | 1750.0 | ||
| 11774 | Vessels, Heights and Two Versions (Easy Version) | dfs and similar dsu greedy implementation two pointers | Statement | C | Codeforces Round 1102 (Div. 2) {2234} | PROGRAMMING | 1250.0 | ||
| 711 | Tom and Jerry | dfs and similar dsu games trees | Statement | E | Spectral::Cup 2026 Round 3 (Codeforces Round 1110, Div. 1 + Div. 2) {2245} | PROGRAMMING | 2500.0 |