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Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 5302 | Two Paths | dfs and similar dp graphs shortest paths trees two pointers | Statement | D | Codeforces Beta Round 14 (Div. 2) {14} | PROGRAMMING | Codeforces Beta Round #14 tutorial | 2100 | |
| 2103 | Scheme | dfs and similar graphs trees | Statement | E | Codeforces Beta Round 22 (Div. 2 Only) {22} | PROGRAMMING | Codeforces Beta Round #22 Tutorial | 2400 | |
| 244 | Baldman and the military | dfs and similar graphs trees | Statement | E | Codeforces Beta Round 41 {42} | PROGRAMMING | Solution of task е, Codeforces beta round #41 | 2700 | |
| 822 | Caterpillar | dfs and similar dp graphs trees | Statement | F | Codeforces Beta Round 48 {51} | PROGRAMMING | 2600 | ||
| 7676 | Eternal Victory | dfs and similar graphs greedy shortest paths trees | Statement | D | Codeforces Beta Round 57 (Div. 2) {61} | PROGRAMMING | Round 57-A | 1900 | |
| 402 | Pairs | dfs and similar dp dsu graphs implementation trees | Statement | E | Yandex.Algorithm Open 2011: Qualification 1 {81} | PROGRAMMING | 2600 | ||
| 1058 | 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 | |
| 433 | Leaders | dfs and similar dsu graphs trees | Statement | E | Yandex.Algorithm 2011: Finals {97} | PROGRAMMING | Финал Яндекс.Алгоритм: разбор A-B | 2800 | |
| 43799 | Party | dfs and similar graphs trees | Statement | A | Codeforces Beta Round 87 (Div. 1 Only) {115} | PROGRAMMING | Tutorial | 1300 | |
| 12612 | Choosing Capital for Treeland | dfs and similar dp graphs trees | Statement | D | Codeforces Round 135 (Div. 2) {219} | PROGRAMMING | User editorial for Codeforces Round #135 (Div. 2) | 1900 | |
| 2332 | Cactus | data structures dfs and similar dp graphs trees | Statement | E | Codeforces Round 143 (Div. 2) {231} | PROGRAMMING | Tutorial Codeforces Round #143 | 2400 | |
| 621 | T-decomposition | dfs and similar graphs greedy trees | Statement | D | Codeforces Round 147 (Div. 2) {237} | PROGRAMMING | Codeforces Round #147 (Div. 2) Разбор Задач | 2200 | |
| 551 | Balance | constructive algorithms dfs and similar graphs trees | Statement | C | Codeforces Round 188 (Div. 1) {317} | PROGRAMMING | Analysis | 2700 | |
| 6924 | Water Tree | data structures dfs and similar graphs trees | Statement | D | Codeforces Round 200 (Div. 1) {343} | PROGRAMMING | Codeforces Round #200 Tutorial | 2100 | |
| 916 | Pumping Stations | brute force dfs and similar divide and conquer flows graphs greedy trees | Statement | E | Codeforces Round 200 (Div. 1) {343} | PROGRAMMING | Codeforces Round #200 Tutorial | 2800 | |
| 12114 | Valera and Elections | dfs and similar graphs trees | Statement | C | Codeforces Round 216 (Div. 2) {369} | PROGRAMMING | Editorial Codeforces Round #216 (Div. 2) | 1700 | |
| 733 | Ksenia and Pawns | dfs and similar graphs implementation trees | Statement | D | Codeforces Round 224 (Div. 2) {382} | PROGRAMMING | Codeforces Round #224 (Div. 2) Editorial | 2300 | |
| 2642 | Information Graph | dfs and similar dsu graphs trees | Statement | E | Codeforces Round 266 (Div. 2) {466} | PROGRAMMING | Editorial Codeforces Round #266 (Div. 2) | 2400 | |
| 2863 | Tourists | data structures dfs and similar graphs trees | Statement | E | Codeforces Round 278 (Div. 1) {487} | PROGRAMMING | Tutorial | 3100 | |
| 3282 | New Year Santa Network | combinatorics dfs and similar graphs trees | Statement | D | Good Bye 2014 {500} | PROGRAMMING | Tutorial 2 | 1900 | |
| 19016 | Reposts | *special dfs and similar dp graphs trees | Statement | A | VK Cup 2015 - Qualification Round 1 {522} | PROGRAMMING | Разбор задач VK Cup 2015 — Квалификация 1 | 1700 | |
| 2695 | Work Group | dfs and similar dp graphs strings trees | Statement | B | VK Cup 2015 - Round 2 (unofficial online mirror, Div. 1 only) {533} | PROGRAMMING | 2000 | ||
| 2996 | Case of Computer Network | dfs and similar graphs trees | Statement | E | Codeforces Round 310 (Div. 1) {555} | PROGRAMMING | Codeforces Round #310 Editorial | 2800 | |
| 9141 | Tree Requests | binary search bitmasks constructive algorithms dfs and similar graphs trees | Statement | D | Codeforces Round 316 (Div. 2) {570} | PROGRAMMING | Codeforces Round #316 Editorial | 2400 | |
| 1256 | Bribes | dfs and similar graphs trees | Statement | B | Bubble Cup 8 - Finals [Online Mirror] {575} | PROGRAMMING | Bubble Cup finals 2015 Results and Editorial | 2300 | |
| 56157 | Kefa and Park | dfs and similar graphs trees | Statement | C | Codeforces Round 321 (Div. 2) {580} | PROGRAMMING | Codeforces Round #321 Editorial | 1500 | |
| 2974 | Super M | dfs and similar dp graphs trees | Statement | D | Codeforces Round 328 (Div. 2) {592} | PROGRAMMING | Codeforces Round #328 Problem Analysis | 2200 | |
| 1430 | Happy Tree Party | data structures dfs and similar graphs math trees | Statement | D | Codeforces Round 329 (Div. 2) {593} | PROGRAMMING | 2300 | ||
| 10388 | Minimum spanning tree for each edge | data structures dfs and similar dsu graphs trees | Statement | E | Educational Codeforces Round 3 {609} | PROGRAMMING | Editorial | 2100 | |
| 4094 | Kingdom and its Cities | dfs and similar divide and conquer dp graphs sortings trees | Statement | D | Codeforces Round 339 (Div. 1) {613} | PROGRAMMING | Tutorial | 2800 | |
| 1003 | Preorder Test | binary search dfs and similar dp graphs greedy trees | Statement | D | 8VC Venture Cup 2016 - Final Round {627} | PROGRAMMING | 8VC Venture Cup 2016 — Final Round Editorial | 2600 | |
| 251 | 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 | |
| 1400 | The Chocolate Spree | dfs and similar dp graphs trees | Statement | F | Manthan, Codefest 16 {633} | PROGRAMMING | Manthan, Codefest 16: Editorials | 2500 | |
| 2321 | Road Improvement | *special dfs and similar graphs greedy trees | Statement | C | VK Cup 2016 - Qualification Round 2 {638} | PROGRAMMING | 2100 | ||
| 450 | Bear and Chemistry | data structures dfs and similar graphs trees | Statement | F | VK Cup 2016 - Round 1 {639} | PROGRAMMING | Tutorial | 3300 | |
| 2891 | Pursuit For Artifacts | dfs and similar dsu graphs trees | Statement | E | Educational Codeforces Round 10 {652} | PROGRAMMING | Editorial of Educational Codeforces Round 10 | 2300 | |
| 1743 | 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 | |
| 1891 | Gifts by the List | constructive algorithms dfs and similar graphs trees | Statement | D | Codeforces Round 357 (Div. 2) {681} | PROGRAMMING | 45425 | 2100 | |
| 8105 | Alyona and the Tree | dfs and similar dp graphs trees | Statement | C | Codeforces Round 358 (Div. 2) {682} | PROGRAMMING | 45491 | 1700 | |
| 5039 | Brain Network (medium) | dfs and similar graphs trees | Statement | C2 | Helvetic Coding Contest 2016 online mirror (teams, unrated) {690} | PROGRAMMING | Tutotial | 1600 | |
| 6202 | Fix a Tree | constructive algorithms dfs and similar dsu graphs trees | Statement | B | Codeforces Round 363 (Div. 1) {698} | PROGRAMMING | 46148 | 1700 | |
| 4652 | Connecting Universities | dfs and similar dp graphs trees | Statement | B | Codeforces Round 364 (Div. 1) {700} | PROGRAMMING | 46283 | 2100 | |
| 4416 | Centroids | data structures dfs and similar dp graphs greedy trees | Statement | C | AIM Tech Round 3 (Div. 1) {708} | PROGRAMMING | Editorial | 2500 | |
| 5142 | Alyona and a tree | binary search data structures dfs and similar graphs trees | Statement | B | Codeforces Round 381 (Div. 1) {739} | PROGRAMMING | 48582 | 2000 | |
| 4735 | Chloe and pleasant prizes | dfs and similar dp graphs trees | Statement | D | Codeforces Round 384 (Div. 2) {743} | PROGRAMMING | Codeforces Round #384 Editorial | 1800 | |
| 722 | Santa Clauses and a Soccer Championship | constructive algorithms dfs and similar graphs trees | Statement | F | Technocup 2017 - Elimination Round 3 {748} | PROGRAMMING | Codeforces Round 389 (Div.2) Editorial | 2500 | |
| 15123 | 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 | |
| 552 | Broken Tree | dfs and similar dp graphs greedy trees | Statement | E | Codeforces Round 392 (Div. 2) {758} | PROGRAMMING | Codeforces Round #392 (Div. 2) Editorial | 2900 | |
| 2381 | Dasha and Puzzle | constructive algorithms dfs and similar graphs greedy trees | Statement | E | Codeforces Round 394 (Div. 2) {761} | PROGRAMMING | Codeforces Round #394 (Div. 2) [Editorial] | 2000 | |
| 11914 | 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 | |
| 4655 | Garland | dfs and similar graphs greedy trees | Statement | C | Codeforces Round 398 (Div. 2) {767} | PROGRAMMING | Codeforces Round #398 (Div. 2) Editorial | 2000 | |
| 10045 | Andryusha and Colored Balloons | dfs and similar graphs greedy trees | Statement | C | Технокубок 2017 - Финал (только для онсайт-финалистов) {780} | PROGRAMMING | Technocup 2017 Finals and Codeforces Round #403 Editorial | 1500 | |
| 7273 | Police Stations | constructive algorithms dfs and similar dp graphs shortest paths trees | Statement | D | Codeforces Round 408 (Div. 2) {796} | PROGRAMMING | Tutorial | 2100 | |
| 6581 | Send the Fool Further! (easy) | dfs and similar graphs trees | Statement | J1 | Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} | PROGRAMMING | helvetic-coding-contest-2017-editorial.pdf | 1400 | |
| 6421 | Send the Fool Further! (easy) | dfs and similar graphs trees | Statement | J | Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} | PROGRAMMING | helvetic-coding-contest-2017-editorial.pdf | 1500 | |
| 350 | Sagheer and Kindergarten | dfs and similar graphs implementation trees | Statement | D | Codeforces Round 417 (Div. 2) {812} | PROGRAMMING | [Editorial] Codeforces Round #417 (Div. 2) | 2700 | |
| 1481 | Tree Queries | dfs and similar graphs trees | Statement | G | Educational Codeforces Round 25 {825} | PROGRAMMING | Educational Codeforces Round 25 - Editorial | 2600 | |
| 1383 | Best Edge Weight | data structures dfs and similar graphs trees | Statement | D | Codeforces Round 423 (Div. 1, rated, based on VK Cup Finals) {827} | PROGRAMMING | Codeforces Round #423 Analysis | 2700 | |
| 4539 | Misha, Grisha and Underground | dfs and similar graphs trees | Statement | D | Codeforces Round 425 (Div. 2) {832} | PROGRAMMING | Codeforces Round #425 (Div.2) Editorial | 1900 | |
| 1253 | Roads in the Kingdom | dfs and similar dp graphs trees | Statement | F | Codeforces Round 427 (Div. 2) {835} | PROGRAMMING | Editorial | 2400 | |
| 20329 | Journey | dfs and similar dp graphs probabilities trees | Statement | C | Codeforces Round 428 (Div. 2) {839} | PROGRAMMING | Codeforces Round #428 editorial | 1500 | |
| 3777 | Ilya And The Tree | dfs and similar graphs math number theory trees | Statement | C | Codeforces Round 430 (Div. 2) {842} | PROGRAMMING | Tutorial Codeforces Round #430 (Div. 2) | 2000 | |
| 502 | Nikita and game | binary search dfs and similar divide and conquer graphs trees | Statement | E | Codeforces Round 430 (Div. 2) {842} | PROGRAMMING | Tutorial Codeforces Round #430 (Div. 2) | 3000 | |
| 408 | Upgrading Tree | constructive algorithms dfs and similar graphs math trees | Statement | C | AIM Tech Round 4 (Div. 1) {843} | PROGRAMMING | AIM Tech Round 4 -- Editorial | 2900 | |
| 749 | Dating | brute force dfs and similar graphs trees | Statement | I | Bubble Cup X - Finals [Online Mirror] {852} | PROGRAMMING | Tutorial | 2500 | |
| 284 | Harry Vs Voldemort | dfs and similar dp graphs trees | Statement | G | Manthan, Codefest 17 {855} | PROGRAMMING | 54750 | 3000 | |
| 2120 | Desk Disorder | combinatorics dfs and similar dsu graphs trees | Statement | E | MemSQL Start[c]UP 3.0 - Round 1 {859} | PROGRAMMING | Tutorial | 2100 | |
| 26087 | Mahmoud and Ehab and the bipartiteness | dfs and similar graphs trees | Statement | B | Codeforces Round 435 (Div. 2) {862} | PROGRAMMING | Codeforces round #435 editorial | 1400 | |
| 675 | Cities Excursions | dfs and similar graphs trees | Statement | F | Codeforces Round 436 (Div. 2) {864} | PROGRAMMING | Codeforces Round #436 (Div.2) Разбор | 2700 | |
| 1317 | 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 | |
| 2300 | Tree Destruction | constructive algorithms dfs and similar graphs greedy trees | Statement | F | Educational Codeforces Round 35 (Rated for Div. 2) {911} | PROGRAMMING | T | 2500 | |
| 8437 | Peculiar apple-tree | dfs and similar graphs trees | Statement | A | Codeforces Round 468 (Div. 1, based on Technocup 2018 Final Round) {930} | PROGRAMMING | Codeforces Round #468 and Technocup 2018 Final Round Analysis | 1500 | |
| 748 | Maximum Control (medium) | data structures dfs and similar graphs greedy trees | Statement | B2 | Helvetic Coding Contest 2018 online mirror (teams allowed, unrated) {958} | PROGRAMMING | helvetic-coding-contest-2018-editorial.pdf | 2400 | |
| 1596 | Simple Cycles Edges | dfs and similar graphs trees | Statement | F | Educational Codeforces Round 42 (Rated for Div. 2) {962} | PROGRAMMING | Educational Codeforces Round 42 Editorial | 2400 | |
| 16125 | Cut 'em all! | dfs and similar dp graphs greedy trees | Statement | C | Codeforces Round 484 (Div. 2) {982} | PROGRAMMING | Editorial | 1500 | |
| 6591 | We Need More Bosses | dfs and similar graphs trees | Statement | E | Educational Codeforces Round 46 (Rated for Div. 2) {1000} | PROGRAMMING | 60288 | 2100 | |
| 11710 | Military Problem | dfs and similar graphs trees | Statement | E | Codeforces Round 498 (Div. 3) {1006} | PROGRAMMING | 60672 | 1600 | |
| 2585 | Mars rover | dfs and similar graphs implementation trees | Statement | D | Codeforces Round 499 (Div. 1) {1010} | PROGRAMMING | 60851 | 2100 | |
| 1010 | 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 | |
| 19317 | Valid BFS? | dfs and similar graphs shortest paths trees | Statement | D | Manthan, Codefest 18 (rated, Div. 1 + Div. 2) {1037} | PROGRAMMING | Tutorial | 1700 | |
| 1492 | Leaf Sets | data structures dfs and similar dsu graphs greedy sortings trees | Statement | F | Codeforces Round 510 (Div. 2) {1042} | PROGRAMMING | Tutorial | 2400 | |
| 830 | Hyperspace Highways | dfs and similar graphs trees | Statement | C | Bubble Cup 11 - Finals [Online Mirror, Div. 1] {1045} | PROGRAMMING | Tutorial (PDF) | 2500 | |
| 6746 | Decorate Apple Tree | constructive algorithms dfs and similar dp graphs greedy sortings trees | Statement | D | Mail.Ru Cup 2018 Round 3 {1056} | PROGRAMMING | Mail.Ru Cup 2018 Round 3 Editorial | 1600 | |
| 1162 | Construct a tree | binary search constructive algorithms dfs and similar graphs greedy trees | Statement | C | Codeforces Round 530 (Div. 1) {1098} | PROGRAMMING | 64331 | 2300 | |
| 1121 | Tree | data structures dfs and similar dp graphs trees | Statement | E | CodeCraft-19 and Codeforces Round 537 (Div. 2) {1111} | PROGRAMMING | CodeCraft-19 and Codeforces Round #537 (Div. 2) Editorial | 2800 | |
| 1782 | 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 | |
| 3838 | 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 | |
| 16870 | Edgy Trees | dfs and similar dsu graphs math trees | Statement | C | Codeforces Round 548 (Div. 2) {1139} | PROGRAMMING | Codeforces Round #548 Editorial | 1500 | |
| 2550 | Privatization of Roads in Treeland | binary search constructive algorithms dfs and similar graphs greedy trees | Statement | G | Codeforces Round 547 (Div. 3) {1141} | PROGRAMMING | 66062 | 2500 | |
| 13697 | Cover it! | dfs and similar dsu graphs shortest paths trees | Statement | E | Codeforces Round 565 (Div. 3) {1176} | PROGRAMMING | 67598 | 1700 | |
| 1062 | Daleks' Invasion (medium) | dfs and similar graphs shortest paths trees | Statement | E2 | Helvetic Coding Contest 2019 online mirror (teams allowed, unrated) {1184} | PROGRAMMING | helvetic-coding-contest-2019-editorial.pdf | 2200 | |
| 1367 | 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 | |
| 3012 | 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 | |
| 2078 | The Maximum Subtree | dfs and similar dp graphs trees | Statement | F | Educational Codeforces Round 74 (Rated for Div. 2) {1238} | PROGRAMMING | Educational Codeforces Round 74 Editorial | 2300 | |
| 9394 | 0-1 MST | dfs and similar dsu graphs sortings | Statement | B | Codeforces Round 599 (Div. 1) {1242} | PROGRAMMING | Codeforces Round #599 Editorial | 1900 | |
| 957 | Economic Difficulties | data structures dfs and similar dp flows graphs trees | Statement | F | Codeforces Round 603 (Div. 2) {1263} | PROGRAMMING | Разбор Codeforces Round #603 (Div. 2) | 2500 | |
| 3044 | Jeremy Bearimy | dfs and similar graphs greedy trees | Statement | C | Codeforces Round 607 (Div. 1) {1280} | PROGRAMMING | Codeforces Round #607 Editorial | 2000 | |
| 5509 | Numbers on Tree | constructive algorithms data structures dfs and similar graphs greedy trees | Statement | B | Codeforces Round 612 (Div. 1) {1286} | PROGRAMMING | Codeforces Round #612 - Editorial | 2000 | |
| 530 | Around the World | bitmasks combinatorics dfs and similar dp graphs graphs math trees | Statement | D | Codeforces Round 618 (Div. 1) {1299} | PROGRAMMING | 1750.0 | Codeforces Round #618 Editorial | 2900 |
| 5372 | Kuroni and the Celebration | constructive algorithms dfs and similar graphs interactive trees | Statement | D | Ozon Tech Challenge 2020 (Div.1 + Div.2, Rated, T-shirts + prizes!) {1305} | PROGRAMMING | 1750.0 | Ozon Tech Challenge 2020 Editorial | 1900 |
| 13218 | Maximum White Subtree | dfs and similar dp graphs trees | Statement | F | Codeforces Round 627 (Div. 3) {1324} | PROGRAMMING | Codeforces Round #627 (Div. 3) Editorial | ||
| 11871 | Tree Queries | dfs and similar graphs trees | Statement | E | Codeforces Round 629 (Div. 3) {1328} | PROGRAMMING | 75246 | 2100 | |
| 1073 | Nastya and Time Machine | constructive algorithms dfs and similar graphs trees | Statement | D | Codeforces Round 637 (Div. 1) - Thanks, Ivan Belonogov! {1340} | PROGRAMMING | 1750.0 | Codeforces Round #637 Editorial | |
| 999 | James and the Chase | dfs and similar graphs probabilities trees | Statement | E | Codeforces Round 647 (Div. 1) - Thanks, Algo Muse! {1361} | PROGRAMMING | 3000.0 | Codeforces Round #647 Editorial | 3000 |
| 4995 | Ehab's Last Corollary | constructive algorithms data structures dfs and similar dp graphs implementation trees | Statement | D | Codeforces Round 649 (Div. 2) {1364} | PROGRAMMING | 2000.0 | Codeforces round #649 editorial | 2100 |
| 1800 | The Hidden Pair (Easy Version) | binary search dfs and similar graphs interactive shortest paths trees | Statement | F1 | Codeforces Round 651 (Div. 2) {1370} | PROGRAMMING | 2000.0 | Editorial — Codeforces Round #651 | |
| 1683 | The Hidden Pair (Hard Version) | binary search dfs and similar graphs interactive shortest paths trees | Statement | F2 | Codeforces Round 651 (Div. 2) {1370} | PROGRAMMING | 1250.0 | Editorial — Codeforces Round #651 | |
| 6919 | Captain Flint and Treasure | data structures dfs and similar dp graphs greedy implementation trees | Statement | D | Codeforces Round 660 (Div. 2) {1388} | PROGRAMMING | 2000.0 | Codeforces Round #660 Editorial | 2000 |
| 496 | Directing Edges | dfs and similar dp graphs greedy trees | Statement | G | Educational Codeforces Round 92 (Rated for Div. 2) {1389} | PROGRAMMING | 80809 | ||
| 1937 | Pairs of Pairs | constructive algorithms dfs and similar graphs trees | Statement | E | Codeforces Round 663 (Div. 2) {1391} | PROGRAMMING | 2750.0 | Codeforces Round #663 (Div. 2) Editorial | |
| 236 | Star Trek | *special combinatorics dfs and similar dp games graphs matrices trees | Statement | C | Central-European Olympiad in Informatics, CEOI 2020, Day 1 (IOI, Unofficial Mirror Contest, Unrated) {1402} | PROGRAMMING | Editorial | ||
| 395 | Spring cleaning | *special data structures dfs and similar graphs trees | Statement | B | Central-European Olympiad in Informatics, CEOI 2020, Day 2 (IOI, Unofficial Mirror Contest, Unrated) {1403} | PROGRAMMING | CEOI 2020 Online Mirror — Day 2 Tutorial | ||
| 11819 | Link Cut Centroids | constructive algorithms dfs and similar graphs trees | Statement | C | Codeforces Round 670 (Div. 2) {1406} | PROGRAMMING | 1500.0 | Codeforces Round #670 (Div. 2) Editorial | |
| 2732 | 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 |
| 6674 | 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 | ||
| 1541 | BFS Trees | combinatorics dfs and similar graphs math shortest paths trees | Statement | D | Codeforces Round 706 (Div. 1) {1495} | PROGRAMMING | 2000.0 | Codeforces Round #706 Editorial | |
| 2085 | Phoenix and Earthquake | constructive algorithms dfs and similar dsu graphs greedy trees | Statement | F | Codeforces Global Round 14 {1515} | PROGRAMMING | 3250.0 | Editorial | |
| 907 | Off by One | constructive algorithms dfs and similar geometry graphs sortings trees | Statement | E | Educational Codeforces Round 108 (Rated for Div. 2) {1519} | PROGRAMMING | Educational Codeforces Round 108 Editorial | ||
| 2314 | Nastia Plays with a Tree | constructive algorithms data structures dfs and similar dp flows graphs greedy implementation trees | Statement | D | Codeforces Round 720 (Div. 2) {1521} | PROGRAMMING | 2250.0 | 90477 | |
| 3562 | How Many Paths? | dfs and similar dp graphs trees | Statement | G | Codeforces Round 731 (Div. 3) {1547} | PROGRAMMING | Codeforces Round #731 (Div. 3) Editorial | ||
| 3081 | 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 |
| 4456 | Buds Re-hanging | dfs and similar graphs greedy trees | Statement | E | Codeforces Global Round 16 {1566} | PROGRAMMING | 2000.0 | Codeforces Global Round 16 Editorial | |
| 9183 | Bakry and Partitioning | bitmasks constructive algorithms dfs and similar dp graphs trees | Statement | C | Codeforces Round 746 (Div. 2) {1592} | PROGRAMMING | 1500.0 | 95583 | |
| 3261 | Treelabeling | bitmasks constructive algorithms dfs and similar games graphs greedy trees | Statement | D | Codeforces Round 754 (Div. 2) {1605} | PROGRAMMING | 2000.0 | tutorial | 2100 |
| 2139 | X(or)-mas Tree | 2-sat bitmasks dfs and similar graphs trees | Statement | D | Codeforces Global Round 18 {1615} | PROGRAMMING | 2250.0 | Global Round 18 Editorial | |
| 1034 | Christmas Chocolates | dfs and similar dp games graphs implementation math number theory shortest paths trees | Statement | E | Codeforces Round 761 (Div. 2) {1617} | PROGRAMMING | 3000.0 | Editorial for Codeforces Round #761 (Div. 2) | |
| 1155 | 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) | |
| 664 | 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) | |
| 516 | 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 | |
| 24406 | White-Black Balanced Subtrees | dfs and similar dp graphs trees | Statement | G | Codeforces Round 790 (Div. 4) {1676} | PROGRAMMING | Codeforces Round #790 (Div. 4) Editorial | ||
| 1144 | 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 | |
| 1924 | DFS Trees | data structures dfs and similar dsu graphs greedy trees | Statement | C | Codeforces Round 808 (Div. 1) {1707} | PROGRAMMING | 1250.0 | 104930 | |
| 4174 | Edge Split | brute force constructive algorithms dfs and similar graphs probabilities trees | Statement | D | Codeforces Round 819 (Div. 1 + Div. 2) and Grimoire of Code Annual Contest 2022 {1726} | PROGRAMMING | 2000.0 | Codeforces Round #819 (Div. 1 + Div. 2) and Grimoire of Code Annual Contest 2022 Editorial | |
| 3762 | 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> | |
| 6286 | Reset K Edges | binary search data structures dfs and similar graphs greedy trees | Statement | D | Educational Codeforces Round 136 (Rated for Div. 2) {1739} | PROGRAMMING | Educational Codeforces Round 136 Editorial | ||
| 18420 | Masha and a Beautiful Tree | dfs and similar divide and conquer graphs sortings trees | Statement | D | Codeforces Round 826 (Div. 3) {1741} | PROGRAMMING | 107908 | ||
| 10424 | SlavicG's Favorite Problem | bitmasks brute force constructive algorithms data structures dfs and similar graphs greedy | Statement | G | Codeforces Round 835 (Div. 4) {1760} | PROGRAMMING | 109348 | ||
| 872 | Maximizing Root | dfs and similar dp graphs math trees | Statement | F | Codeforces Round 848 (Div. 2) {1778} | PROGRAMMING | 2750.0 | Codeforces Round #848 (Div. 2) Editorial | |
| 1176 | 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 | |
| 4025 | Timofey and Black-White Tree | brute force dfs and similar divide and conquer graphs greedy math shortest paths trees | Statement | F | Codeforces Round 847 (Div. 3) {1790} | PROGRAMMING | 111948 | ||
| 1922 | 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) | |
| 3942 | 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!) | |
| 5143 | Fish Graph | brute force constructive algorithms dfs and similar graphs trees | Statement | B | Codeforces Round 869 (Div. 1) {1817} | PROGRAMMING | 1000.0 | Codeforces Round #869 (Div.1, Div.2) Editorial | |
| 7706 | Gardening Friends | brute force dfs and similar dp graphs trees | Statement | F | Codeforces Round 867 (Div. 3) {1822} | PROGRAMMING | Codeforces Round #867 (Div. 3) Editorial | ||
| 20622 | Copil Copac Draws Trees | dfs and similar dp graphs trees | Statement | A | Codeforces Round 875 (Div. 1) {1830} | PROGRAMMING | 500.0 | Codeforces Round #875 (Div.1 + Div. 2) Editorial | |
| 2726 | Autosynthesis | 2-sat constructive algorithms dfs and similar dp flows graphs trees | Statement | C | Codeforces Round 902 (Div. 1, based on COMPFEST 15 - Final Round) {1876} | PROGRAMMING | 1250.0 | Codeforces Round #902 (Div. 1, Div. 2, based on COMPFEST 15 — Final Round) Editorial | |
| 9669 | Minimum Maximum Distance | dfs and similar dp graphs shortest paths trees | Statement | F | Codeforces Round 903 (Div. 3) {1881} | PROGRAMMING | 121327 | ||
| 941 | Game of Stacks | dfs and similar graphs implementation trees | Statement | D | Codeforces Round 906 (Div. 1) {1889} | PROGRAMMING | 2000.0 | Codeforces Round 906 Editorial | |
| 180 | Doremy's Swapping Trees | dfs and similar graphs trees | Statement | E | Codeforces Round 906 (Div. 1) {1889} | PROGRAMMING | 3500.0 | Codeforces Round 906 Editorial | |
| 1993 | Compressed Tree | dfs and similar dp graphs greedy trees | Statement | E | Educational Codeforces Round 158 (Rated for Div. 2) {1901} | PROGRAMMING | Educational Codeforces Round 158 Editorial | ||
| 519 | Beautiful Tree | data structures dfs and similar graphs trees | Statement | F | Codeforces Round 914 (Div. 2) {1904} | PROGRAMMING | 3500.0 | Codeforces Round 914 (Div. 2) Editorial | |
| 1123 | Caterpillar on a Tree | binary search dfs and similar graphs greedy implementation trees | Statement | F | Codeforces Round 922 (Div. 2) {1918} | PROGRAMMING | 3000.0 | Codeforces Round #922 (Div. 2) Editorial | |
| 4575 | Vlad and Trouble at MIT | dfs and similar dp flows graphs greedy implementation trees | Statement | G | Codeforces Round 928 (Div. 4) {1926} | PROGRAMMING | 126132 | ||
| 5437 | Microcycle | data structures dfs and similar dsu graphs greedy trees | Statement | F | Codeforces Round 923 (Div. 3) {1927} | PROGRAMMING | 125597 | ||
| 307 | Evidence Board | *special constructive algorithms dfs and similar graphs trees | Statement | B | XVIII Open Olympiad in Informatics - Final Stage, Day 1 (Unrated, Online Mirror, IOI rules) {1939} | PROGRAMMING | |||
| 43 | 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 | |||
| 881 | Min-Fund Prison (Medium) | brute force dfs and similar dp graphs trees | Statement | G2 | Helvetic Coding Contest 2024 online mirror (teams allowed, unrated) {1970} | PROGRAMMING | Helvetic Coding Contest 2024 Editorial | 2200 | |
| 549 | Min-Fund Prison (Hard) | bitmasks dfs and similar dp graphs trees | Statement | G3 | Helvetic Coding Contest 2024 online mirror (teams allowed, unrated) {1970} | PROGRAMMING | Helvetic Coding Contest 2024 Editorial | 2400 | |
| 1715 | Yasya and the Mysterious Tree | bitmasks data structures dfs and similar graphs strings trees | Statement | G | Codeforces Round 950 (Div. 3) {1980} | PROGRAMMING | 130135 | ||
| 7466 | 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 | |
| 1071 | Choose Your Queries | dfs and similar dp graphs greedy trees | Statement | F | Educational Codeforces Round 170 (Rated for Div. 2) {2025} | PROGRAMMING | Educational Codeforces Round 170 Editorial | ||
| 3953 | 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 | |
| 2690 | Control of Randomness | combinatorics dfs and similar graphs greedy math probabilities trees | Statement | E | Codeforces Round 992 (Div. 2) {2040} | PROGRAMMING | 2250.0 | Codeforces Round #992 (Div.2) Editorial | |
| 3887 | 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 | ||
| 4540 | Resourceful Caterpillar Sequence | dfs and similar dp games graphs implementation trees | Statement | E | Good Bye 2024: 2025 is NEAR {2053} | PROGRAMMING | 2000.0 | Good Bye 2024: 2025 is NEAR Editorial | |
| 458 | The Game (Hard Version) | data structures dfs and similar games graphs trees | Statement | E2 | Ethflow Round 1 (Codeforces Round 1001, Div. 1 + Div. 2) {2062} | PROGRAMMING | 2500.0 | Ethflow Round 1 (Codeforces Round 1001, Div. 1 + Div. 2) Editorial | |
| 4357 | The Game (Easy Version) | dfs and similar games graphs trees | Statement | E1 | Ethflow Round 1 (Codeforces Round 1001, Div. 1 + Div. 2) {2062} | PROGRAMMING | 1500.0 | Ethflow Round 1 (Codeforces Round 1001, Div. 1 + Div. 2) Editorial | |
| 7197 | Skibidus and Slay | data structures dfs and similar graphs greedy trees | Statement | F | Codeforces Round 1003 (Div. 4) {2065} | PROGRAMMING | Video Tutorial | ||
| 899 | Spruce Dispute | constructive algorithms dfs and similar graphs implementation shortest paths trees | Statement | E | Codeforces Round 1022 (Div. 2) {2108} | PROGRAMMING | 2750.0 | Codeforces Round 1022 Editorial | |
| 4349 | 1-1-1, Free Tree! | data structures dfs and similar graphs trees | Statement | F | Codeforces Round 1037 (Div. 3) {2126} | PROGRAMMING | 144845 | ||
| 853 | 23 Rises Again | brute force data structures dfs and similar dp flows graphs implementation probabilities trees | Statement | H | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) {2127} | PROGRAMMING | 4000.0 | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) Editorial | |
| 6469 | Root was Built by Love, Broken by Destiny | combinatorics dfs and similar graphs trees | Statement | D | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) {2127} | PROGRAMMING | 2000.0 | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) Editorial | |
| 5502 | Maple and Tree Beauty (Easy Version) | dfs and similar dp graphs trees | Statement | C1 | Codeforces Round 1048 (Div. 1) {2138} | PROGRAMMING | 1250.0 | Codeforces Round 1048 (Div. 1, Div. 2) Editorial | |
| 4841 | Catshock | constructive algorithms dfs and similar graphs trees | Statement | D | Codeforces Round 1060 (Div. 2) {2154} | PROGRAMMING | 1750.0 | Codeforces Round 1060 (Div. 2) Editorial | |
| 671 | 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 | |
| 4019 | Cherry Tree | dfs and similar dp graphs trees | Statement | F | Codeforces Round 1072 (Div. 3) {2184} | PROGRAMMING | Codeforces Round 1072 (Div. 3) Editorial | ||
| 1410 | Jerry and Tom | data structures dfs and similar games graphs greedy trees | Statement | C | Codeforces Round 1077 (Div. 1) {2187} | PROGRAMMING | 1750.0 | Codeforces Round 1077 (Div. 1, Div. 2) Editorial | |
| 4462 | 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 | |
| 1946 | 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 | |
| 190 | Statistics on Tree | binary search brute force dfs and similar divide and conquer graphs trees | Statement | G | Spectral::Cup 2026 Round 1 (Codeforces Round 1094, Div. 1 + Div. 2) {2222} | PROGRAMMING | 3500.0 | Spectral::Cup 2026 Round 1 (Codeforces Round 1094, Div. 1 + Div. 2) Editorial |