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Name
Tags
Solutions
Index
Contest
Type
Points
Tutorial
Rating Level
6589 Mike and Shortcuts dfs and similar graphs greedy shortest paths Statement B Codeforces Round 361 (Div. 2) {689} PROGRAMMING 45912 1600
4991 Brain Network (medium) dfs and similar graphs trees Statement C2 Helvetic Coding Contest 2016 online mirror (teams, unrated) {690} PROGRAMMING Tutotial 1600
6481 Swaps in Permutation dfs and similar dsu math Statement D Educational Codeforces Round 14 {691} PROGRAMMING Editorial of Educational Codeforces Round 14 1700
3796 Puzzles dfs and similar math probabilities trees Statement B Codeforces Round 362 (Div. 1) {696} PROGRAMMING Codeforces Round #362 (Editorial) 1800
6172 Fix a Tree constructive algorithms dfs and similar dsu graphs trees Statement B Codeforces Round 363 (Div. 1) {698} PROGRAMMING 46148 1700
4634 Connecting Universities dfs and similar dp graphs trees Statement B Codeforces Round 364 (Div. 1) {700} PROGRAMMING 46283 2100
1458 Break Up dfs and similar graphs Statement C Codeforces Round 364 (Div. 1) {700} PROGRAMMING 46283 2700
2970 Persistent Bookcase bitmasks data structures dfs and similar implementation Statement D Codeforces Round 368 (Div. 2) {707} PROGRAMMING 46662 2100
4337 Centroids data structures dfs and similar dp graphs greedy trees Statement C AIM Tech Round 3 (Div. 1) {708} PROGRAMMING Editorial 2500
5763 Generate a String dfs and similar dp Statement E Educational Codeforces Round 16 {710} PROGRAMMING Editorial of Educational Codeforces Round 16 2100
4956 Directed Roads combinatorics dfs and similar graphs math Statement D Codeforces Round 369 (Div. 2) {711} PROGRAMMING 46830 1900
2574 Digit Tree dfs and similar divide and conquer dsu trees Statement C Codeforces Round 372 (Div. 1) {715} PROGRAMMING Codeforces Round #372 Editorial 2800
1580 Paint it really, really dark gray dfs and similar Statement E Bubble Cup 9 - Finals [Online Mirror] {717} PROGRAMMING Tutorial 1900
463 Cactusophobia dfs and similar flows Statement B Russian Code Cup 2016 - Finals [Unofficial Mirror, Div. 1 Only Recommended] {720} PROGRAMMING Russian Code Cup 2016 — Results and Tutorial 2300
3345 Generating Sets binary search data structures dfs and similar greedy strings trees Statement D Intel Code Challenge Elimination Round (Div. 1 + Div. 2, combined) {722} PROGRAMMING Tutorial 1900
7493 Lakes in Berland dfs and similar dsu graphs greedy implementation Statement D Codeforces Round 375 (Div. 2) {723} PROGRAMMING 1600
2249 One-Way Reform constructive algorithms dfs and similar flows graphs greedy Statement E Codeforces Round 375 (Div. 2) {723} PROGRAMMING Codeforces Round #375 (Div.2) Editorial 2300
17930 Transformation: from A to B brute force dfs and similar math Statement A Technocup 2017 - Elimination Round 1 (Unofficially Open for Everyone, Rated for Div. 2) {727} PROGRAMMING Tutorial 1100
1373 Bulmart binary search dfs and similar Statement C 2016-2017 ACM-ICPC, NEERC, Southern Subregional Contest (Online Mirror, ACM-ICPC Rules, Teams Preferred) {730} PROGRAMMING Разбор задач (видео, по-русски) 2200
7789 Socks dfs and similar dsu graphs greedy Statement C Codeforces Round 376 (Div. 2) {731} PROGRAMMING 47840 1600
3243 Tourist Reform dfs and similar graphs Statement F Codeforces Round 377 (Div. 2) {732} PROGRAMMING Codeforces Round #377 (Div. 2) Editorial 2400
5093 Anton and Tree dfs and similar dp trees Statement E Codeforces Round 379 (Div. 2) {734} PROGRAMMING Tutorial of Codeforces Round #379 (Div. 2) 2100
5101 Alyona and a tree binary search data structures dfs and similar graphs trees Statement B Codeforces Round 381 (Div. 1) {739} PROGRAMMING 48582 2000
5691 Arpa's loud Owf and Mehrdad's evil plan dfs and similar math Statement A Codeforces Round 383 (Div. 1) {741} PROGRAMMING Codeforces Round #383 editorial 1600
5897 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
3101 Arpa’s overnight party and Mehrdad’s silent entering constructive algorithms dfs and similar graphs Statement C Codeforces Round 383 (Div. 1) {741} PROGRAMMING Codeforces Round #383 editorial 2600
3584 Arpa’s letter-marked tree and Mehrdad’s Dokhtar-kosh paths data structures dfs and similar trees Statement D Codeforces Round 383 (Div. 1) {741} PROGRAMMING Codeforces Round #383 editorial 2700
4707 Chloe and pleasant prizes dfs and similar dp graphs trees Statement D Codeforces Round 384 (Div. 2) {743} PROGRAMMING Codeforces Round #384 Editorial 1800
9701 Hongcow Builds A Nation dfs and similar graphs Statement A Codeforces Round 385 (Div. 1) {744} PROGRAMMING Codeforces Round #385 Editorial 1500
2092 Comments dfs and similar expression parsing implementation strings Statement E Codeforces Round 387 (Div. 2) {747} PROGRAMMING 49171 1700
714 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
3166 New Year and Fireworks brute force data structures dfs and similar dp implementation Statement D Good Bye 2016 {750} PROGRAMMING Good Bye 2016 — hints and codes 1900
238 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
14948 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
3216 Pavel and barbecue constructive algorithms dfs and similar Statement A 8VC Venture Cup 2017 - Final Round {756} PROGRAMMING 8VC Venture Cup 2017 — Final Round and Codeforces Round #393 Editorial 1600
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
2368 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
11856 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
1336 Tree Folding dfs and similar dp greedy implementation trees Statement E Codeforces Round 397 by Kaspersky Lab and Barcelona Bootcamp (Div. 1 + Div. 2 combined) {765} PROGRAMMING Codeforces Round #397 Editorial 2200
3894 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
3455 Mahmoud and a xor trip bitmasks constructive algorithms data structures dfs and similar dp math trees Statement E Codeforces Round 396 (Div. 2) {766} PROGRAMMING Codeforces round #396 editorial 2200
4631 Garland dfs and similar graphs greedy trees Statement C Codeforces Round 398 (Div. 2) {767} PROGRAMMING Codeforces Round #398 (Div. 2) Editorial 2000
6953 Code For 1 constructive algorithms dfs and similar divide and conquer Statement B Divide by Zero 2017 and Codeforces Round 399 (Div. 1 + Div. 2, combined) {768} PROGRAMMING Editorial Divide by Zero and Codeforces Round #399 (Div. 1+2, combined) 1600
3003 Cycle In Maze *special dfs and similar graphs greedy shortest paths Statement C VK Cup 2017 - Qualification 1 {769} PROGRAMMING Tutorial 1800
2927 Online Courses In BSU *special dfs and similar graphs implementation Statement C VK Cup 2017 - Qualification 2 {770} PROGRAMMING 1900
17686 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
3545 Bear and Tree Jumps dfs and similar dp trees Statement C VK Cup 2017 - Round 1 {771} PROGRAMMING VK Cup 2017 Round 1 and CF Round 405 — Editorial 2100
6167 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
2532 Bitwise Formula bitmasks brute force dfs and similar expression parsing implementation Statement B Codeforces Round 402 (Div. 1) {778} PROGRAMMING Codeforces Round #402, Editorial 2000
981 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
10003 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
2966 Underground Lab constructive algorithms dfs and similar graphs Statement E Технокубок 2017 - Финал (только для онсайт-финалистов) {780} PROGRAMMING Technocup 2017 Finals and Codeforces Round #403 Editorial 2200
2840 Berzerk dfs and similar dp games Statement A Codeforces Round 406 (Div. 1) {786} PROGRAMMING Codeforces Round #406 Editorial 2100
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
2883 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
2569 The Great Mixing dfs and similar graphs shortest paths Statement C Codeforces Round 407 (Div. 1) {788} PROGRAMMING Codeforces Round #407(Div.1 + Div.2) Editorial 2500
4822 Igor and his way to work dfs and similar graphs implementation shortest paths Statement B Tinkoff Challenge - Elimination Round {793} PROGRAMMING 51685 1600
305 Problem of offices constructive algorithms dfs and similar dp trees Statement E Tinkoff Challenge - Elimination Round {793} PROGRAMMING 51685 2800
910 Labelling Cities dfs and similar graphs hashing Statement D Tinkoff Challenge - Final Round (Codeforces Round 414, rated, Div. 1 + Div. 2) {794} PROGRAMMING 2400
7148 Police Stations constructive algorithms dfs and similar dp graphs shortest paths trees Statement D Codeforces Round 408 (Div. 2) {796} PROGRAMMING Tutorial 2100
2177 Broken BST data structures dfs and similar Statement D Educational Codeforces Round 19 {797} PROGRAMMING 51588 2200
6516 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
369 Send the Fool Further! (hard) dfs and similar dp math trees Statement J3 Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} PROGRAMMING helvetic-coding-contest-2017-editorial.pdf 2400
364 Send the Fool Further! (hard) dfs and similar dp math trees Statement L Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} PROGRAMMING helvetic-coding-contest-2017-editorial.pdf 2800
1929 Ice cream coloring constructive algorithms dfs and similar greedy Statement C Codeforces Round 411 (Div. 1) {804} PROGRAMMING Codeforces Round #411 Editorial 2200
1555 Expected diameter of a tree binary search brute force dfs and similar dp sortings trees Statement D Codeforces Round 411 (Div. 1) {804} PROGRAMMING Codeforces Round #411 Editorial 2600
215 Fake bullions combinatorics dfs and similar dp graphs number theory Statement F Codeforces Round 411 (Div. 1) {804} PROGRAMMING Codeforces Round #411 Editorial 3400
1900 Vladik and Favorite Game constructive algorithms dfs and similar graphs interactive Statement D Codeforces Round 416 (Div. 2) {811} PROGRAMMING 2000
349 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
8102 The Tag Game dfs and similar graphs Statement C Educational Codeforces Round 22 {813} PROGRAMMING 52410 1700
2577 An overnight dance in discotheque dfs and similar dp geometry greedy trees Statement D Codeforces Round 418 (Div. 2) {814} PROGRAMMING Codeforces Round #418 (Div. 2) Editorial 2000
1639 Okabe and City dfs and similar graphs shortest paths Statement D Codeforces Round 420 (Div. 2) {821} PROGRAMMING Tutorial 2200
373 Madness constructive algorithms dfs and similar trees Statement F Codeforces Round 422 (Div. 2) {822} PROGRAMMING Codeforces Round #422 (Div. 2) Editorial 2700
4290 Minimal Labels data structures dfs and similar graphs greedy Statement E Educational Codeforces Round 25 {825} PROGRAMMING Educational Codeforces Round 25 - Editorial 2400
1466 Tree Queries dfs and similar graphs trees Statement G Educational Codeforces Round 25 {825} PROGRAMMING Educational Codeforces Round 25 - Editorial 2600
1370 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
4438 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
1233 Roads in the Kingdom dfs and similar dp graphs trees Statement F Codeforces Round 427 (Div. 2) {835} PROGRAMMING Editorial 2400
1067 Diverging Directions data structures dfs and similar trees Statement B IndiaHacks 2nd Elimination 2017 (unofficial, unrated mirror, ICPC rules) {838} PROGRAMMING 53736 2100
20004 Journey dfs and similar dp graphs probabilities trees Statement C Codeforces Round 428 (Div. 2) {839} PROGRAMMING Codeforces Round #428 editorial 1500
2805 Leha and another game about graph constructive algorithms data structures dfs and similar dp graphs Statement B Codeforces Round 429 (Div. 1) {840} PROGRAMMING Editorial 2100
3754 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
500 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
5949 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
407 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
2139 Shortest Path Problem? dfs and similar graphs math Statement G Educational Codeforces Round 27 {845} PROGRAMMING 53986 2400
1026 Chemistry in Berland dfs and similar greedy trees Statement E Educational Codeforces Round 28 {846} PROGRAMMING 54357 2400
1650 Noise Level dfs and similar Statement I 2017-2018 ACM-ICPC, NEERC, Southern Subregional Contest, qualification stage (Online Mirror, ACM-ICPC Rules, Teams Preferred) {847} PROGRAMMING 2000
347 Berland SU Computer Network dfs and similar hashing trees Statement L 2017-2018 ACM-ICPC, NEERC, Southern Subregional Contest, qualification stage (Online Mirror, ACM-ICPC Rules, Teams Preferred) {847} PROGRAMMING 2500
733 Dating brute force dfs and similar graphs trees Statement I Bubble Cup X - Finals [Online Mirror] {852} PROGRAMMING Tutorial 2500
282 Harry Vs Voldemort dfs and similar dp graphs trees Statement G Manthan, Codefest 17 {855} PROGRAMMING 54750 3000
2017 Wizard's Tour constructive algorithms dfs and similar graphs Statement F Технокубок 2018 - Отборочный Раунд 1 {858} PROGRAMMING Codeforces Round 434 Div.1+Div.2 (and Technocup 2018 — Elimination Round 1) Editorial 2400
2112 Desk Disorder combinatorics dfs and similar dsu graphs trees Statement E MemSQL Start[c]UP 3.0 - Round 1 {859} PROGRAMMING Tutorial 2100
505 Arkady and a Nobody-men data structures dfs and similar trees Statement E Codeforces Round 434 (Div. 1, based on Technocup 2018 Elimination Round 1) {860} PROGRAMMING Codeforces Round 434 Div.1+Div.2 (and Technocup 2018 — Elimination Round 1) Editorial 2600
25463 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
279 The Overdosing Ubiquity brute force dfs and similar graphs Statement D Codeforces Round 439 (Div. 2) {869} PROGRAMMING Tutorial 2800
1315 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
2360 National Property 2-sat dfs and similar graphs implementation Statement C Codeforces Round 441 (Div. 1, by Moscow Team Olympiad) {875} PROGRAMMING Codeforces Round #441. Editorial. 2100
5063 Olya and Energy Drinks data structures dfs and similar graphs shortest paths Statement D Codeforces Round 442 (Div. 2) {877} PROGRAMMING 55362 1900
1515 Orientation of Edges dfs and similar graphs Statement G 2017-2018 ACM-ICPC, NEERC, Southern Subregional Contest (Online Mirror, ACM-ICPC Rules, Teams Preferred) {883} PROGRAMMING 2000
5164 Bertown Subway dfs and similar greedy math Statement C Educational Codeforces Round 31 {884} PROGRAMMING 55470 1500
236 Sloth dfs and similar dp graph matchings trees Statement D Codeforces Round 446 (Div. 1) {891} PROGRAMMING Codeforces Round #446 Editorial 3000
28068 Rumor dfs and similar graphs greedy Statement C Educational Codeforces Round 33 (Rated for Div. 2) {893} PROGRAMMING 55989 1300
3789 Nephren gives a riddle binary search dfs and similar Statement A Codeforces Round 449 (Div. 1) {896} PROGRAMMING Codeforces Round #449 Editorial 1700
1298 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
630 Weighting a Tree constructive algorithms dfs and similar graphs Statement D Codeforces Round 453 (Div. 1) {901} PROGRAMMING Codeforces Round #453 (Div. 1 & Div. 2) Editorial 2700
11925 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
2456 Coprocessor dfs and similar dp graphs greedy Statement E Codeforces Round 455 (Div. 2) {909} PROGRAMMING Codeforces Round #455 (Div. 2) Editorial 2100
13952 The Way to Home dfs and similar dp greedy implementation Statement A Testing Round 14 (Unrated) {910} PROGRAMMING 1100
2263 Tree Destruction constructive algorithms dfs and similar graphs greedy trees Statement F Educational Codeforces Round 35 (Rated for Div. 2) {911} PROGRAMMING T 2500
2037 Prime Gift binary search dfs and similar math meet-in-the-middle number theory two pointers Statement E Codeforces Round 456 (Div. 2) {912} PROGRAMMING Codeforces Round #456 (Div. 2) Editorial 2600
4030 Almost Acyclic Graph dfs and similar graphs Statement D Educational Codeforces Round 36 (Rated for Div. 2) {915} PROGRAMMING 57123 2200
3987 MADMAX dfs and similar dp games graphs Statement B Codeforces Round 459 (Div. 1) {917} PROGRAMMING Codeforces Round #459 Editorial 1800
12197 Substring dfs and similar dp graphs Statement D Codeforces Round 460 (Div. 2) {919} PROGRAMMING Codeforces Round #460 (Div. 2) Editorial 1700
9957 Swap Adjacent Elements dfs and similar greedy math sortings two pointers Statement C Educational Codeforces Round 37 (Rated for Div. 2) {920} PROGRAMMING T 1500
7683 Connected Components? data structures dfs and similar dsu graphs Statement E Educational Codeforces Round 37 (Rated for Div. 2) {920} PROGRAMMING T 2100
8374 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
9155 Recursive Queries binary search data structures dfs and similar Statement B ICM Technex 2018 and Codeforces Round 463 (Div. 1 + Div. 2, combined) {932} PROGRAMMING 57796 1300
978 Fafa and Ancient Mathematics dfs and similar dp trees Statement E Codeforces Round 465 (Div. 2) {935} PROGRAMMING editorial 2500
3409 Sleepy Game dfs and similar dp games graphs Statement B Codeforces Round 467 (Div. 1) {936} PROGRAMMING Codeforces Round #467, Editorial 2100
252 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
8100 Love Rescue dfs and similar dsu graphs greedy strings Statement D Codeforces Round 464 (Div. 2) {939} PROGRAMMING Analysis of Codeforces Round #464 1600
15292 Protect Sheep brute force dfs and similar graphs implementation Statement A Codeforces Round 470 (rated, Div. 2, based on VK Cup 2018 Round 1) {948} PROGRAMMING VK Cup 2018 Round 1 and CF Round #470 (div. 1 & 2) editorial 1000
2248 Data Center Maintenance dfs and similar graphs Statement C Codeforces Round 469 (Div. 1) {949} PROGRAMMING 58291 2000
7854 Fight Against Traffic dfs and similar graphs shortest paths Statement D Educational Codeforces Round 40 (Rated for Div. 2) {954} PROGRAMMING 58519 1600
745 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
2265 Alternating Tree combinatorics dfs and similar divide and conquer dp probabilities trees Statement E Divide by Zero 2018 and Codeforces Round 474 (Div. 1 + Div. 2, combined) {960} PROGRAMMING Divide by Zero 2018 and Codeforces Round #474 (Div. 1 + Div. 2, combined) Editorial 2200
1579 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
2996 Destruction of a Tree constructive algorithms dfs and similar dp greedy trees Statement B 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) 2100
20474 Divide by three, multiply by two dfs and similar math sortings Statement D Codeforces Round 479 (Div. 3) {977} PROGRAMMING Codeforces Round #479 (Div. 3) Editorial 1400
25449 Cyclic Components dfs and similar dsu graphs Statement E Codeforces Round 479 (Div. 3) {977} PROGRAMMING Codeforces Round #479 (Div. 3) Editorial 1500
7322 Kuro and Walking Route dfs and similar trees Statement C Codeforces Round 482 (Div. 2) {979} PROGRAMMING Codeforces Round #482 (Div. 2) Editorial 1600
15746 Cut 'em all! dfs and similar dp graphs greedy trees Statement C Codeforces Round 484 (Div. 2) {982} PROGRAMMING Editorial 1500
222 The Meeting Place Cannot Be Changed dfs and similar graphs Statement F Codeforces Round 484 (Div. 2) {982} PROGRAMMING Editorial 2800
2710 AND Graph bitmasks dfs and similar dsu graphs Statement C Codeforces Round 485 (Div. 1) {986} PROGRAMMING Codeforces Round #485 Editorial 2300
1056 Flow Control dfs and similar dp greedy trees Statement F Educational Codeforces Round 45 (Rated for Div. 2) {990} PROGRAMMING Educational Codeforces Round 45 Editorial 2500
7808 Reachability from the Capital dfs and similar graphs greedy Statement E Codeforces Round 490 (Div. 3) {999} PROGRAMMING 60138 1900
6462 We Need More Bosses dfs and similar graphs trees Statement E Educational Codeforces Round 46 (Rated for Div. 2) {1000} PROGRAMMING 60288 2100
2098 Berland and the Shortest Paths brute force dfs and similar graphs shortest paths Statement F Codeforces Round 496 (Div. 3) {1005} PROGRAMMING Codeforces Round 496 (Div. 3): Problem Tutorials 2400
11572 Military Problem dfs and similar graphs trees Statement E Codeforces Round 498 (Div. 3) {1006} PROGRAMMING 60672 1600
2560 Mars rover dfs and similar graphs implementation trees Statement D Codeforces Round 499 (Div. 1) {1010} PROGRAMMING 60851 2100
4381 Chemical table constructive algorithms dfs and similar dsu graphs matrices Statement B Codeforces Round 500 (Div. 1) [based on EJOI] {1012} PROGRAMMING 60920 1900
1024 Road Projects dfs and similar dp trees Statement F Educational Codeforces Round 48 (Rated for Div. 2) {1016} PROGRAMMING Разбор Educational Codeforces Round 48 2600
24991 Badge brute force dfs and similar graphs Statement B Codeforces Round 503 (by SIS, Div. 2) {1020} PROGRAMMING Codeforces Round #503 (based on SIS olympiad) — Editorial 1000
1008 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
8343 Mouse Hunt dfs and similar graphs Statement D Educational Codeforces Round 49 (Rated for Div. 2) {1027} PROGRAMMING Educational Codeforces Round 49 Editorial 1700
1945 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
15824 King Escape dfs and similar graphs implementation Statement A Lyft Level 5 Challenge 2018 - Elimination Round {1033} PROGRAMMING The Lyft Level 5 Challenge 2018 Elimination Round (Div. 1 + Div. 2) Editorial 1000
787 Hidden Bipartite Graph binary search constructive algorithms dfs and similar graphs interactive Statement E Lyft Level 5 Challenge 2018 - Elimination Round {1033} PROGRAMMING The Lyft Level 5 Challenge 2018 Elimination Round (Div. 1 + Div. 2) Editorial 2700
431 Sources and Sinks bitmasks brute force dfs and similar Statement G Educational Codeforces Round 50 (Rated for Div. 2) {1036} PROGRAMMING 61727 2800
18984 Valid BFS? dfs and similar graphs shortest paths trees Statement D Manthan, Codefest 18 (rated, Div. 1 + Div. 2) {1037} PROGRAMMING Tutorial 1700
1094 Maximum Matching bitmasks brute force dfs and similar dp graphs Statement E Codeforces Round 508 (Div. 2) {1038} PROGRAMMING Tutorial 2400
1487 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
1467 Leaf Sets data structures dfs and similar dsu graphs greedy sortings trees Statement F Codeforces Round 510 (Div. 2) {1042} PROGRAMMING Tutorial 2400
1706 Intersecting Subtrees dfs and similar interactive trees Statement B Lyft Level 5 Challenge 2018 - Final Round {1044} PROGRAMMING Lyft Level 5 Challenge 2018 — Final Round — Editorial 1900
827 Hyperspace Highways dfs and similar graphs trees Statement C Bubble Cup 11 - Finals [Online Mirror, Div. 1] {1045} PROGRAMMING Tutorial (PDF) 2500
6713 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
7437 Bmail Computer Network *special dfs and similar trees Statement A Mail.Ru Cup 2018 - Practice Round {1057} PROGRAMMING 1700
3491 Sergey and Subway dfs and similar dp trees Statement E Codeforces Round 513 by Barcelona Bootcamp (rated, Div. 1 + Div. 2) {1060} PROGRAMMING User editorial for Codeforces Round 513 by Barcelona Bootcamp (rated, Div. 1 + Div. 2) 2000
4164 Fun with Integers dfs and similar graphs implementation math Statement D Codeforces Round 520 (Div. 2) {1062} PROGRAMMING Tutorial 1800
2050 Company binary search data structures dfs and similar greedy trees Statement E Codeforces Round 520 (Div. 2) {1062} PROGRAMMING Tutorial 2300
981 Upgrading Cities dfs and similar graphs Statement F Codeforces Round 520 (Div. 2) {1062} PROGRAMMING Tutorial 3000
1444 Three Pieces dfs and similar dp shortest paths Statement D Educational Codeforces Round 52 (Rated for Div. 2) {1065} PROGRAMMING Educational Codeforces Round 52 Editorial 2200
1324 Up and Down the Tree dfs and similar dp trees Statement F Educational Codeforces Round 52 (Rated for Div. 2) {1065} PROGRAMMING Educational Codeforces Round 52 Editorial 2500
2857 Multihedgehog dfs and similar graphs shortest paths Statement B Codeforces Round 518 (Div. 1) [Thanks, Mail.Ru!] {1067} PROGRAMMING Tutorial 2000
592 Choosing Two Paths dfs and similar dp greedy trees Statement F Educational Codeforces Round 53 (Rated for Div. 2) {1073} PROGRAMMING 62742 2800
127 Harder Satisfiability 2-sat dfs and similar graphs Statement H 2018-2019 ICPC, NEERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1089} PROGRAMMING 3500
10725 Tree with Maximum Cost dfs and similar dp trees Statement F Codeforces Round 527 (Div. 3) {1092} PROGRAMMING Codeforces Round #527 (Div. 3) Editorial 2100
1978 Minimal Diameter Forest constructive algorithms dfs and similar greedy trees Statement E Codeforces Round 527 (Div. 3) {1092} PROGRAMMING Codeforces Round #527 (Div. 3) Editorial 2500
11299 Beautiful Graph dfs and similar graphs Statement D Educational Codeforces Round 56 (Rated for Div. 2) {1093} PROGRAMMING 63877 1600
9534 Sum in the tree constructive algorithms dfs and similar greedy trees Statement A Codeforces Round 530 (Div. 1) {1098} PROGRAMMING 64331 1600
1161 Construct a tree binary search constructive algorithms dfs and similar graphs greedy trees Statement C Codeforces Round 530 (Div. 1) {1098} PROGRAMMING 64331 2300
1033 Cookies binary search data structures dfs and similar dp games trees Statement F Codeforces Round 530 (Div. 2) {1099} PROGRAMMING E 2300
2610 Andrew and Taxi binary search dfs and similar graphs Statement E Codeforces Round 532 (Div. 2) {1100} PROGRAMMING Unofficial Tutorial 2200
5406 GCD Counting data structures dfs and similar dp number theory trees Statement D Educational Codeforces Round 58 (Rated for Div. 2) {1101} PROGRAMMING 64483 2000
953 Johnny Solving constructive algorithms dfs and similar graphs math Statement C Codeforces Round 534 (Div. 1) {1103} PROGRAMMING Codeforces Round #534 — Editorial 2800
4417 Kilani and the Game dfs and similar graphs implementation shortest paths Statement D Codeforces Round 533 (Div. 2) {1105} PROGRAMMING Tutorial 1900
19541 Lunar New Year and a Wander data structures dfs and similar graphs greedy shortest paths Statement D Codeforces Round 536 (Div. 2) {1106} PROGRAMMING Tutorial 1500
1091 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
6684 Tree Cutting (Easy Version) dfs and similar trees Statement F1 Codeforces Round 540 (Div. 3) {1118} PROGRAMMING 65396 1800
631 Tree Cutting (Hard Version) combinatorics dfs and similar dp trees Statement F2 Codeforces Round 540 (Div. 3) {1118} PROGRAMMING 65396 2700
1768 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
9395 Connect brute force dfs and similar dsu Statement C Codeforces Round 542 [Alex Lopashev Thanks-Round] (Div. 2) {1130} PROGRAMMING 65520 1400
3618 Gourmet choice dfs and similar dp dsu graphs greedy Statement D Codeforces Round 541 (Div. 2) {1131} PROGRAMMING Codeforces Round #541 Editorial 2000
1957 Knapsack dfs and similar dp greedy Statement E Educational Codeforces Round 61 (Rated for Div. 2) {1132} PROGRAMMING T 2400
3799 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
16575 Edgy Trees dfs and similar dsu graphs math trees Statement C Codeforces Round 548 (Div. 2) {1139} PROGRAMMING Codeforces Round #548 Editorial 1500
2543 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
3719 Lynyrd Skynyrd data structures dfs and similar dp math trees Statement B Codeforces Round 549 (Div. 1) {1142} PROGRAMMING Codeforces Round #549 Editorial 2300
17542 Queen dfs and similar trees Statement C Codeforces Round 549 (Div. 2) {1143} PROGRAMMING Codeforces Round #549 Editorial 1400
14010 Graph Without Long Directed Paths dfs and similar graphs Statement F Codeforces Round 550 (Div. 3) {1144} PROGRAMMING 66307 1700
1203 Frog Jumping dfs and similar math number theory Statement D Forethought Future Cup - Elimination Round {1146} PROGRAMMING 66639 2100
856 Palindrome XOR dfs and similar graphs Statement D Forethought Future Cup - Final Round (Onsite Finalists Only) {1147} PROGRAMMING Forethought Future Cup Final Round Tutorial 2600
9302 Neko Performs Cat Furrier Transform bitmasks constructive algorithms dfs and similar math Statement B Codeforces Round 554 (Div. 2) {1152} PROGRAMMING T 1300
1123 Neko and Flashback constructive algorithms dfs and similar graphs Statement E Codeforces Round 554 (Div. 2) {1152} PROGRAMMING T 2500
5524 Serval and Rooted Tree binary search dfs and similar dp greedy trees Statement D Codeforces Round 551 (Div. 2) {1153} PROGRAMMING Editorial 1800
6569 Ugly Pairs dfs and similar greedy implementation sortings strings Statement B Educational Codeforces Round 64 (Rated for Div. 2) {1156} PROGRAMMING 66827 1800
4642 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
2114 Permutation recovery constructive algorithms data structures dfs and similar graphs greedy math sortings Statement C Codeforces Round 559 (Div. 1) {1158} PROGRAMMING 66993 2300
25784 News Distribution dfs and similar dsu graphs Statement C Educational Codeforces Round 65 (Rated for Div. 2) {1167} PROGRAMMING 67058 1400
4403 Nauuo and Circle combinatorics dfs and similar dp trees Statement B Codeforces Round 564 (Div. 1) {1172} PROGRAMMING Codeforces Round #564 Editorial 2000
4517 Minimal Segment Cover data structures dfs and similar divide and conquer dp greedy implementation trees Statement E Educational Codeforces Round 66 (Rated for Div. 2) {1175} PROGRAMMING Editorial 2200
13502 Cover it! dfs and similar dsu graphs shortest paths trees Statement E Codeforces Round 565 (Div. 3) {1176} PROGRAMMING 67598 1700
5689 Recover it! dfs and similar graphs greedy number theory sortings Statement D Codeforces Round 565 (Div. 3) {1176} PROGRAMMING 67598 1900
2279 Short Colorful Strip combinatorics dfs and similar dp Statement F1 Codeforces Global Round 4 {1178} PROGRAMMING E 2200
600 The Awesomest Vertex data structures dfs and similar Statement G Codeforces Global Round 4 {1178} PROGRAMMING E 2900
11995 Plus from Picture dfs and similar implementation strings Statement B Codeforces Round 566 (Div. 2) {1182} PROGRAMMING 67614 1300
1001 Complete Mirror constructive algorithms dfs and similar dp hashing implementation trees Statement D Codeforces Round 566 (Div. 2) {1182} PROGRAMMING 67614 2500
1057 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
994 Vus the Cossack and a Graph dfs and similar graphs greedy implementation Statement F Codeforces Round 571 (Div. 2) {1186} PROGRAMMING E 2300
11197 Tree Painting dfs and similar dp trees Statement E Educational Codeforces Round 67 (Rated for Div. 2) {1187} PROGRAMMING Разбор Educational Codeforces Round 67 2000
1296 Add on a Tree: Revolution constructive algorithms dfs and similar implementation trees Statement A2 Codeforces Round 572 (Div. 1) {1188} PROGRAMMING Editorial of Codeforces Round #572 2500
1539 Dynamic Diameter *special data structures dfs and similar divide and conquer trees Statement B CEOI 2019 day 1 online mirror (unrated, IOI format) {1192} PROGRAMMING E
1163 Graph Traveler brute force data structures dfs and similar dp graphs implementation math number theory Statement F Codeforces Round 578 (Div. 2) {1200} PROGRAMMING Codeforces Round #578 (Div. 2) Editorial 2500
1216 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
3290 Bits And Pieces bitmasks dfs and similar dp greedy Statement F Manthan, Codefest 19 (open for everyone, rated, Div. 1 + Div. 2) {1208} PROGRAMMING 69357 2600
10701 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
1362 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
3013 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
7164 Treasure Island dfs and similar dp flows hashing Statement D Codeforces Round 583 (Div. 1 + Div. 2, based on Olympiad of Metropolises) {1214} PROGRAMMING Tutorial 1800
458 Tiles Placement constructive algorithms dfs and similar trees Statement H Codeforces Round 583 (Div. 1 + Div. 2, based on Olympiad of Metropolises) {1214} PROGRAMMING Tutorial 2700
5934 Coloring Edges constructive algorithms dfs and similar graphs Statement D Educational Codeforces Round 72 (Rated for Div. 2) {1217} PROGRAMMING Educational Codeforces Round 72 Editorial 2000
734 The Light Square 2-sat dfs and similar greedy Statement I Bubble Cup 12 - Finals [Online Mirror, unrated, Div. 1] {1218} PROGRAMMING E 2200
157 Function Composition dfs and similar Statement H Bubble Cup 12 - Finals [Online Mirror, unrated, Div. 1] {1218} PROGRAMMING E 2700
2999 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
211 Alice and the Cactus dfs and similar graphs math probabilities Statement F Codeforces Round 593 (Div. 2) {1236} PROGRAMMING 70654 2900
2051 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
2591 Catowice City 2-sat dfs and similar graph matchings graphs Statement D Codeforces Round 594 (Div. 1) {1239} PROGRAMMING Editorial of Codeforces Round #594 (on the problems of Moscow Team Olympiad) 2400
9213 0-1 MST dfs and similar dsu graphs sortings Statement B Codeforces Round 599 (Div. 1) {1242} PROGRAMMING Codeforces Round #599 Editorial 1900
1943 Sum Balance bitmasks dfs and similar dp graphs Statement C Codeforces Round 599 (Div. 1) {1242} PROGRAMMING Codeforces Round #599 Editorial 2400
18358 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
1751 Wires dfs and similar graphs greedy Statement N 2019-2020 ICPC, NERC, Southern and Volga Russian Regional Contest (Online Mirror, ICPC Rules, Teams Preferred) {1250} PROGRAMMING 2200
10229 Harmonious Graph constructive algorithms dfs and similar dsu graphs greedy sortings Statement D Codeforces Round 600 (Div. 2) {1253} PROGRAMMING Editorial 1700
362 Send Tree to Charlie combinatorics dfs and similar dsu trees Statement E Codeforces Round 601 (Div. 1) {1254} PROGRAMMING Codeforces Round #601 Editorial 3200
15973 Secret Passwords dfs and similar dsu graphs Statement D Codeforces Round 603 (Div. 2) {1263} PROGRAMMING Codeforces Round #603 (Div. 2) Editorial 1500
949 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
377 Almost Same Distance dfs and similar graphs Statement F Codeforces Global Round 6 {1266} PROGRAMMING Codeforces Global Round 6 Editorial 2900
2950 Subset with Zero Sum constructive algorithms dfs and similar graphs math Statement G Good Bye 2019 {1270} PROGRAMMING Разбор Goodbye 2019 2700
7866 Nearest Opposite Parity dfs and similar graphs shortest paths Statement E Codeforces Round 605 (Div. 3) {1272} PROGRAMMING Codeforces Round #605 (Div. 3) Editorial 2000
5647 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
2041 Tests for problem D constructive algorithms dfs and similar divide and conquer trees Statement E Educational Codeforces Round 78 (Rated for Div. 2) {1278} PROGRAMMING Educational Codeforces Round 78 Editorial 2200
3038 Jeremy Bearimy dfs and similar graphs greedy trees Statement C Codeforces Round 607 (Div. 1) {1280} PROGRAMMING Codeforces Round #607 Editorial 2000
1220 The Cake Is a Lie constructive algorithms data structures dfs and similar graphs Statement E Codeforces Round 610 (Div. 2) {1282} PROGRAMMING 72461 2400
8588 Dr. Evil Underscores bitmasks brute force dfs and similar divide and conquer dp greedy strings trees Statement D Codeforces Round 613 (Div. 2) {1285} PROGRAMMING Codeforces Round #613 (Div. 2) Editorial 1800
5456 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
2005 Prefix Enlightenment dfs and similar dsu graphs Statement C Codeforces Round 616 (Div. 1) {1290} PROGRAMMING 1750.0 Codeforces Round #616 Editorial 2400
2251 Xenon's Attack on the Gangs combinatorics dfs and similar dp greedy trees Statement C Codeforces Round 614 (Div. 1) {1292} PROGRAMMING 1250.0 Codeforces Round #614 Editorial 2300
6813 Three Paths on a Tree dfs and similar dp greedy trees Statement F Codeforces Round 615 (Div. 3) {1294} PROGRAMMING Codeforces Round #615 (Div. 3) Editorial 2100