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3197 Orchestra brute force implementation Statement A 8VC Venture Cup 2016 - Final Round (Div. 2 Edition) {635} PROGRAMMING 8VC Venture Cup 2016 — Final Round Editorial 1200
2244 Road Improvement *special dfs and similar graphs greedy trees Statement C VK Cup 2016 - Qualification Round 2 {638} PROGRAMMING 2100
791 Three-dimensional Turtle Super Computer brute force dfs and similar graphs Statement D VK Cup 2016 - Qualification Round 2 {638} PROGRAMMING 2200
6976 Bear and Forgotten Tree 3 constructive algorithms graphs trees Statement B VK Cup 2016 - Round 1 {639} PROGRAMMING Tutorial 1600
450 Bear and Chemistry data structures dfs and similar graphs trees Statement F VK Cup 2016 - Round 1 {639} PROGRAMMING Tutorial 3300
3390 Bear and Two Paths constructive algorithms graphs Statement B VK Cup 2016 - Round 3 {643} PROGRAMMING VK Cup 2016 — Round 3 — Editorial 1600
3333 Robot Rapping Results Report binary search dp graphs Statement D CROC 2016 - Elimination Round {645} PROGRAMMING Editorial for CROC 2016 Elimination Round 1800
1342 Путь Робота dfs and similar graphs Statement C Технокубок 2016 - Отборочный Раунд 1 {648} PROGRAMMING 1500.0 Разбор задач Технокубок 2016 — Отборочный Раунд 1 1100
2172 Table Compression dfs and similar dp dsu graphs greedy Statement C Codeforces Round 345 (Div. 1) {650} PROGRAMMING Codeforces Round #345: editorial 2300
2840 Pursuit For Artifacts dfs and similar dsu graphs trees Statement E Educational Codeforces Round 10 {652} PROGRAMMING Editorial of Educational Codeforces Round 10 2300
2916 Delivery Bears binary search flows graphs Statement D IndiaHacks 2016 - Online Edition (Div. 1 + Div. 2) {653} PROGRAMMING IndiaHacks Finals 2016 — Editorial 2100
1735 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
7983 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
1951 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
1654 Graph Coloring dfs and similar graphs Statement B CROC 2016 - Final Round [Private, For Onsite Finalists Only] {662} PROGRAMMING Editorial for CROC 2016 Finals and Codeforces Round #347 2300
2387 World Tour graphs shortest paths Statement B Codeforces Round 349 (Div. 1) {666} PROGRAMMING Codeforces Round #349 Editorial 2100
1961 Theseus and labyrinth graphs implementation shortest paths Statement D Codeforces Round 354 (Div. 2) {676} PROGRAMMING 2000
1945 Vanya and Treasure data structures dp graphs shortest paths Statement D Codeforces Round 355 (Div. 2) {677} PROGRAMMING Codeforces Round #355 (Div. 2) Editorial 2300
342 Bear and Chase brute force dfs and similar graphs implementation math probabilities Statement D Codeforces Round 356 (Div. 1) {679} PROGRAMMING Codeforces Round #356 — Editorial 2900
1874 Gifts by the List constructive algorithms dfs and similar graphs trees Statement D Codeforces Round 357 (Div. 2) {681} PROGRAMMING 45425 2100
8066 Alyona and the Tree dfs and similar dp graphs trees Statement C Codeforces Round 358 (Div. 2) {682} PROGRAMMING 45491 1700
609 Travelling Through the Snow Queen's Kingdom bitmasks brute force divide and conquer graphs Statement E Codeforces Round 359 (Div. 1) {685} PROGRAMMING Codeforces Round #359 Editorial 2700
16448 NP-Hard Problem dfs and similar graphs Statement A Codeforces Round 360 (Div. 1) {687} PROGRAMMING Codeforces Round #360 Editorial [+ Challenges!] 1500
1046 Dividing Kingdom II brute force data structures dsu graphs sortings Statement D Codeforces Round 360 (Div. 1) {687} PROGRAMMING Codeforces Round #360 Editorial [+ Challenges!] 2500
436 TOF dfs and similar graphs Statement E Codeforces Round 360 (Div. 1) {687} PROGRAMMING Codeforces Round #360 Editorial [+ Challenges!] 2800
6577 Mike and Shortcuts dfs and similar graphs greedy shortest paths Statement B Codeforces Round 361 (Div. 2) {689} PROGRAMMING 45912 1600
4989 Brain Network (medium) dfs and similar graphs trees Statement C2 Helvetic Coding Contest 2016 online mirror (teams, unrated) {690} PROGRAMMING Tutotial 1600
733 Photographs (I) Statement E1 Helvetic Coding Contest 2016 online mirror (teams, unrated) {690} PROGRAMMING 1900
147 Photographs (II) Statement E2 Helvetic Coding Contest 2016 online mirror (teams, unrated) {690} PROGRAMMING 2700
6167 Fix a Tree constructive algorithms dfs and similar dsu graphs trees Statement B Codeforces Round 363 (Div. 1) {698} PROGRAMMING 46148 1700
4631 Connecting Universities dfs and similar dp graphs trees Statement B Codeforces Round 364 (Div. 1) {700} PROGRAMMING 46283 2100
1455 Break Up dfs and similar graphs Statement C Codeforces Round 364 (Div. 1) {700} PROGRAMMING 46283 2700
3097 Analysis of Pathes in Functional Graph data structures graphs Statement E Educational Codeforces Round 15 {702} PROGRAMMING 46324 2100
2166 Ant Man dp graphs greedy Statement B Codeforces Round 366 (Div. 1) {704} PROGRAMMING Tutorial 2700
524 Black Widow dp graphs implementation math Statement C Codeforces Round 366 (Div. 1) {704} PROGRAMMING Tutorial 2800
13585 Bakery graphs Statement B Codeforces Round 368 (Div. 2) {707} PROGRAMMING 46662 1300
4334 Centroids data structures dfs and similar dp graphs greedy trees Statement C AIM Tech Round 3 (Div. 1) {708} PROGRAMMING Editorial 2500
4954 Directed Roads combinatorics dfs and similar graphs math Statement D Codeforces Round 369 (Div. 2) {711} PROGRAMMING 46830 1900
3320 Complete The Graph binary search constructive algorithms graphs shortest paths Statement B Codeforces Round 372 (Div. 1) {715} PROGRAMMING Codeforces Round #372 Editorial 2200
451 Complete the Permutations combinatorics fft graphs math Statement E Codeforces Round 372 (Div. 1) {715} PROGRAMMING Codeforces Round #372 Editorial 3400
428 Matvey's Birthday bitmasks graphs Statement E Codeforces Round 373 (Div. 1) {718} PROGRAMMING Codeforces Round #373 — Editorial 3400
6525 Journey dp graphs Statement C Codeforces Round 374 (Div. 2) {721} PROGRAMMING Codeforces Round #374 (Div. 2) Editorial 1800
7492 Lakes in Berland dfs and similar dsu graphs greedy implementation Statement D Codeforces Round 375 (Div. 2) {723} PROGRAMMING 1600
1743 st-Spanning Tree dsu graphs greedy implementation Statement F Codeforces Round 375 (Div. 2) {723} PROGRAMMING Codeforces Round #375 (Div.2) Editorial 2200
2248 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
1500 Xor-matic Number of the Graph bitmasks graphs math number theory trees Statement G Intel Code Challenge Final Round (Div. 1 + Div. 2, Combined) {724} PROGRAMMING Tutorial 2600
2386 Subordinates constructive algorithms data structures graphs greedy sortings Statement E Technocup 2017 - Elimination Round 2 {729} PROGRAMMING Technocup 2017 — Elimination Round 2 (and Codeforces Round 380) Editorial 2000
7782 Socks dfs and similar dsu graphs greedy Statement C Codeforces Round 376 (Div. 2) {731} PROGRAMMING 47840 1600
3239 Tourist Reform dfs and similar graphs Statement F Codeforces Round 377 (Div. 2) {732} PROGRAMMING Codeforces Round #377 (Div. 2) Editorial 2400
1295 Drivers Dissatisfaction data structures dsu graphs trees Statement F Codeforces Round 378 (Div. 2) {733} PROGRAMMING Codeforces Round #378 (Div. 2) editorial 2500
137 Tanya is 5! graph matchings graphs greedy schedules Statement E Codeforces Round 380 (Div. 1, Rated, Based on Technocup 2017 - Elimination Round 2) {737} PROGRAMMING 3300
5098 Alyona and a tree binary search data structures dfs and similar graphs trees Statement B Codeforces Round 381 (Div. 1) {739} PROGRAMMING 48582 2000
214 Recover a functional graph graph matchings Statement D Codeforces Round 381 (Div. 1) {739} PROGRAMMING 48582 3400
3099 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
4706 Chloe and pleasant prizes dfs and similar dp graphs trees Statement D Codeforces Round 384 (Div. 2) {743} PROGRAMMING Codeforces Round #384 Editorial 1800
9699 Hongcow Builds A Nation dfs and similar graphs Statement A Codeforces Round 385 (Div. 1) {744} PROGRAMMING Codeforces Round #385 Editorial 1500
1634 New Roads constructive algorithms graphs trees Statement G Codeforces Round 386 (Div. 2) {746} PROGRAMMING Codeforces Round #386 (Div.2) Editorial 2100
711 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
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
14941 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
917 PolandBall and White-Red graph constructive algorithms graphs shortest paths Statement E 8VC Venture Cup 2017 - Elimination Round {755} PROGRAMMING 8VC Venture Cup 2017 — Elimination Round [Editorial] 2400
19752 PolandBall and Hypothesis brute force graphs math number theory Statement A 8VC Venture Cup 2017 - Elimination Round {755} PROGRAMMING 8VC Venture Cup 2017 — Elimination Round [Editorial] 900
646 Can Bash Save the Day? data structures divide and conquer graphs trees Statement G Codecraft-17 and Codeforces Round 391 (Div. 1 + Div. 2, combined) {757} PROGRAMMING CodeCraft-17 and Codeforces Round #391 (Div. 1 + Div. 2, combined) Editorial 2500
1333 Team Rocket Rises Again data structures graphs shortest paths Statement F Codecraft-17 and Codeforces Round 391 (Div. 1 + Div. 2, combined) {757} PROGRAMMING CodeCraft-17 and Codeforces Round #391 (Div. 1 + Div. 2, combined) Editorial 2700
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
2367 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
478 Tree nesting combinatorics graphs trees Statement F Educational Codeforces Round 17 {762} PROGRAMMING Tutorial 2900
11854 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
644 Timofey and a flat tree data structures graphs hashing shortest paths trees Statement D Codeforces Round 395 (Div. 1) {763} PROGRAMMING Codeforces Round #395 [Editorial] 2800
3891 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
4630 Garland dfs and similar graphs greedy trees Statement C Codeforces Round 398 (Div. 2) {767} PROGRAMMING Codeforces Round #398 (Div. 2) Editorial 2000
3001 Cycle In Maze *special dfs and similar graphs greedy shortest paths Statement C VK Cup 2017 - Qualification 1 {769} PROGRAMMING Tutorial 1800
2925 Online Courses In BSU *special dfs and similar graphs implementation Statement C VK Cup 2017 - Qualification 2 {770} PROGRAMMING 1900
17683 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
1443 Vulnerable Kerbals constructive algorithms dp graphs math number theory Statement C VK Cup 2017 - Round 2 {772} PROGRAMMING VK Cup Round 2 + Codeforces Round #409 Tutorial 2400
799 Perishable Roads dp graphs shortest paths Statement D VK Cup 2017 - Round 3 {773} PROGRAMMING VK Cup 2017 Round 3 + Codeforces Round #412 -- Tutorial 2700
6163 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
511 Sherlock's bet to Moriarty constructive algorithms data structures divide and conquer geometry graphs implementation trees Statement F 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 2700
10001 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
3040 Innokenty and a Football League 2-sat graphs greedy implementation shortest paths strings Statement D Технокубок 2017 - Финал (только для онсайт-финалистов) {780} PROGRAMMING Technocup 2017 Finals and Codeforces Round #403 Editorial 2000
2964 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
1262 Axel and Marston in Bitland bitmasks dp graphs matrices Statement F Технокубок 2017 - Финал (только для онсайт-финалистов) {780} PROGRAMMING Technocup 2017 Finals and Codeforces Round #403 Editorial 2800
7964 Legacy data structures graphs shortest paths Statement B Codeforces Round 406 (Div. 1) {786} PROGRAMMING Codeforces Round #406 Editorial 2600
750 ALT data structures flows graphs trees Statement E Codeforces Round 406 (Div. 1) {786} PROGRAMMING Codeforces Round #406 Editorial 3200
2882 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
2566 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
4821 Igor and his way to work dfs and similar graphs implementation shortest paths Statement B Tinkoff Challenge - Elimination Round {793} PROGRAMMING 51685 1600
1702 Presents in Bankopolis dp graphs shortest paths Statement D Tinkoff Challenge - Elimination Round {793} PROGRAMMING 51685 2100
909 Labelling Cities dfs and similar graphs hashing Statement D Tinkoff Challenge - Final Round (Codeforces Round 414, rated, Div. 1 + Div. 2) {794} PROGRAMMING 2400
7146 Police Stations constructive algorithms dfs and similar dp graphs shortest paths trees Statement D Codeforces Round 408 (Div. 2) {796} PROGRAMMING Tutorial 2100
545 Mike and code of a permutation constructive algorithms data structures graphs sortings Statement E Codeforces Round 410 (Div. 2) {798} PROGRAMMING Codeforces Round #410 (Div. 2) Editorial 2700
3664 April Fools' Problem (easy) greedy sortings Statement M1 Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} PROGRAMMING helvetic-coding-contest-2017-editorial.pdf 1200
3620 April Fools' Problem (easy) greedy sortings Statement M Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} PROGRAMMING helvetic-coding-contest-2017-editorial.pdf 1300
6515 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
1486 April Fools' Problem (medium) binary search flows graphs Statement M2 Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} PROGRAMMING helvetic-coding-contest-2017-editorial.pdf 2400
1464 April Fools' Problem (medium) binary search flows graphs Statement N Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} PROGRAMMING helvetic-coding-contest-2017-editorial.pdf 2500
697 Heidi and Library (hard) flows graphs Statement A3 Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} PROGRAMMING helvetic-coding-contest-2017-editorial.pdf 2600
2640 Roma and Poker dp graphs Statement E Educational Codeforces Round 20 {803} PROGRAMMING 51768 2100
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
1560 Card Game binary search flows graphs Statement F Educational Codeforces Round 21 {808} PROGRAMMING 52010 2500
1900 Vladik and Favorite Game constructive algorithms dfs and similar graphs interactive Statement D Codeforces Round 416 (Div. 2) {811} PROGRAMMING 2000
976 Vladik and Entertaining Flags data structures dsu graphs Statement E Codeforces Round 416 (Div. 2) {811} PROGRAMMING Editorial 2600
348 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
8100 The Tag Game dfs and similar graphs Statement C Educational Codeforces Round 22 {813} PROGRAMMING 52410 1700
1696 Bipartite Checking data structures dsu graphs Statement F Educational Codeforces Round 22 {813} PROGRAMMING 52410 2600
725 An unavoidable detour for home combinatorics dp graphs shortest paths Statement E Codeforces Round 418 (Div. 2) {814} PROGRAMMING Codeforces Round #418 (Div. 2) Editorial 2700
1924 Level Generation binary search math ternary search Statement F Educational Codeforces Round 24 {818} PROGRAMMING 52991 2200
1013 Four Melodies flows graphs Statement G Educational Codeforces Round 24 {818} PROGRAMMING 52991 2700
608 Mister B and Flight to the Moon constructive algorithms graphs Statement E Codeforces Round 421 (Div. 1) {819} PROGRAMMING Codeforces Round #421 Editorial 2800
1638 Okabe and City dfs and similar graphs shortest paths Statement D Codeforces Round 420 (Div. 2) {821} PROGRAMMING Tutorial 2200
4281 Minimal Labels data structures dfs and similar graphs greedy Statement E Educational Codeforces Round 25 {825} PROGRAMMING Educational Codeforces Round 25 - Editorial 2400
1465 Tree Queries dfs and similar graphs trees Statement G Educational Codeforces Round 25 {825} PROGRAMMING Educational Codeforces Round 25 - Editorial 2600
1368 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
565 Dirty Arkady's Kitchen data structures dp graphs shortest paths Statement F Codeforces Round 423 (Div. 1, rated, based on VK Cup Finals) {827} PROGRAMMING Codeforces Round #423 Analysis 3100
977 Singer House combinatorics dp graphs trees Statement D Codeforces Round 424 (Div. 1, rated, based on VK Cup Finals) {830} PROGRAMMING Codeforces Round #424 Editorial 2800
338 Perpetual Motion Machine constructive algorithms dp graphs implementation math trees Statement E Codeforces Round 424 (Div. 1, rated, based on VK Cup Finals) {830} PROGRAMMING Codeforces Round #424 Editorial 3100
4434 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
20001 Journey dfs and similar dp graphs probabilities trees Statement C Codeforces Round 428 (Div. 2) {839} PROGRAMMING Codeforces Round #428 editorial 1500
1008 Mother of Dragons brute force graphs math meet-in-the-middle Statement E Codeforces Round 428 (Div. 2) {839} PROGRAMMING Codeforces Round #428 editorial 2600
2803 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
3753 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
1113 Dynamic Shortest Path graphs shortest paths Statement D AIM Tech Round 4 (Div. 1) {843} PROGRAMMING AIM Tech Round 4 -- Editorial 2700
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
472 Maximum Flow flows graphs Statement E AIM Tech Round 4 (Div. 1) {843} PROGRAMMING AIM Tech Round 4 -- Editorial 2900
2135 Shortest Path Problem? dfs and similar graphs math Statement G Educational Codeforces Round 27 {845} PROGRAMMING 53986 2400
455 Shake It! combinatorics dp flows graphs Statement D Codeforces Round 431 (Div. 1) {848} PROGRAMMING Codeforces Round #431 Editorial 2900
461 Tournament Construction constructive algorithms dp graphs greedy math Statement D Codeforces Round 432 (Div. 1, based on IndiaHacks Final Round 2017) {850} PROGRAMMING Codeforces Round #432 editorial 2700
731 Dating brute force dfs and similar graphs trees Statement I Bubble Cup X - Finals [Online Mirror] {852} PROGRAMMING Tutorial 2500
281 Harry Vs Voldemort dfs and similar dp graphs trees Statement G Manthan, Codefest 17 {855} PROGRAMMING 54750 3000
2014 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
2111 Desk Disorder combinatorics dfs and similar dsu graphs trees Statement E MemSQL Start[c]UP 3.0 - Round 1 {859} PROGRAMMING Tutorial 2100
25448 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
2714 1-2-3 graphs implementation Statement C Educational Codeforces Round 29 {863} PROGRAMMING 1800
674 Cities Excursions dfs and similar graphs trees Statement F Codeforces Round 436 (Div. 2) {864} PROGRAMMING Codeforces Round #436 (Div.2) Разбор 2700
157 Hex Dyslexia bitmasks brute force dp graphs Statement E MemSQL Start[c]UP 3.0 - Round 2 (onsite finalists) {865} PROGRAMMING MemSQL Start[c]UP 3.0 Round 2 Editorial 2700
564 Policeman and a Tree dp graphs trees Statement E Codeforces Round 438 by Sberbank and Barcelona Bootcamp (Div. 1 + Div. 2 combined) {868} PROGRAMMING 55046 2600
278 The Overdosing Ubiquity brute force dfs and similar graphs Statement D Codeforces Round 439 (Div. 2) {869} PROGRAMMING Tutorial 2800
1312 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
172 Restore the Tree graphs greedy trees Statement E Codeforces Round 440 (Div. 1, based on Technocup 2018 Elimination Round 2) {871} PROGRAMMING Editorial Codeforces Round 440 Div.1+Div.2 (and Technocup 2018 — Elimination Round 2) 2800
2358 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
1582 Royal Questions dsu graphs greedy Statement F Codeforces Round 441 (Div. 1, by Moscow Team Olympiad) {875} PROGRAMMING Codeforces Round #441. Editorial. 2500
5061 Olya and Energy Drinks data structures dfs and similar graphs shortest paths Statement D Codeforces Round 442 (Div. 2) {877} PROGRAMMING 55362 1900
1024 Tournament data structures graphs Statement C Codeforces Round 443 (Div. 1) {878} PROGRAMMING Editorial 2800
1514 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
421 Berland Army constructive algorithms graphs greedy Statement B 2017-2018 ACM-ICPC, NEERC, Southern Subregional Contest (Online Mirror, ACM-ICPC Rules, Teams Preferred) {883} PROGRAMMING 2800
1278 Anti-Palindromize flows graphs greedy Statement F Educational Codeforces Round 31 {884} PROGRAMMING 55470 2500
1950 Restoration of string constructive algorithms graphs implementation Statement D Технокубок 2018 - Отборочный Раунд 3 {886} PROGRAMMING Editorial Codeforces Round 445 (and Technocup 2018 — Elimination Round 3) 2000
1056 Connecting Vertices dp graphs Statement F Educational Codeforces Round 32 {888} PROGRAMMING Educational Codeforces Round 32 - Editorial 2500
2976 Envy data structures dsu graphs Statement C Codeforces Round 446 (Div. 1) {891} PROGRAMMING Codeforces Round #446 Editorial 2500
28055 Rumor dfs and similar graphs greedy Statement C Educational Codeforces Round 33 (Rated for Div. 2) {893} PROGRAMMING 55989 1300
3057 Ralph and Mushrooms dp graphs Statement E Codeforces Round 447 (Div. 2) {894} PROGRAMMING Codeforces Round #447 (Div.2 Only) Editorial 2400
9036 Dividing the numbers constructive algorithms graphs math Statement C Codeforces Round 452 (Div. 2) {899} PROGRAMMING Codeforces Round #452 (Div.2) Editorial 1300
1296 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
681 Yet Another Maxflow Problem data structures flows graphs Statement G Educational Codeforces Round 34 (Rated for Div. 2) {903} PROGRAMMING Educational Codeforces Round 34 Editorial 2700
1505 Party bitmasks brute force dp graphs Statement C Codeforces Round 454 (Div. 1, based on Technocup 2018 Elimination Round 4) {906} PROGRAMMING Editorial Codeforces Round 454 (and Technocup 2018 — Elimination Round 4) 2300
1605 New Year and Rainbow Roads graphs greedy implementation Statement F Good Bye 2017 {908} PROGRAMMING Good Bye 2017 Editorial 2400
2446 Coprocessor dfs and similar dp graphs greedy Statement E Codeforces Round 455 (Div. 2) {909} PROGRAMMING Codeforces Round #455 (Div. 2) Editorial 2100
2261 Tree Destruction constructive algorithms dfs and similar graphs greedy trees Statement F Educational Codeforces Round 35 (Rated for Div. 2) {911} PROGRAMMING T 2500
2138 Fishes data structures graphs greedy probabilities shortest paths Statement D Codeforces Round 456 (Div. 2) {912} PROGRAMMING Codeforces Round #456 (Div. 2) Editorial 2100
764 Strongly Connected Tournament dp graphs math probabilities Statement F Hello 2018 {913} PROGRAMMING Tutorial 2700
4030 Almost Acyclic Graph dfs and similar graphs Statement D Educational Codeforces Round 36 (Rated for Div. 2) {915} PROGRAMMING 57123 2200
3035 Imbalance Value of a Tree data structures dsu graphs trees Statement F Educational Codeforces Round 36 (Rated for Div. 2) {915} PROGRAMMING 57123 2500
5537 Jamie and Interesting Graph constructive algorithms graphs shortest paths Statement C Codeforces Round 457 (Div. 2) {916} PROGRAMMING Codeforces Round #457 (Div. 2) Editorial 1600
3984 MADMAX dfs and similar dp games graphs Statement B Codeforces Round 459 (Div. 1) {917} PROGRAMMING Codeforces Round #459 Editorial 1800
12184 Substring dfs and similar dp graphs Statement D Codeforces Round 460 (Div. 2) {919} PROGRAMMING Codeforces Round #460 (Div. 2) Editorial 1700
384 A Game With Numbers games graphs shortest paths Statement F Codeforces Round 460 (Div. 2) {919} PROGRAMMING Codeforces Round #460 (Div. 2) Editorial 2800
7681 Connected Components? data structures dfs and similar dsu graphs Statement E Educational Codeforces Round 37 (Rated for Div. 2) {920} PROGRAMMING T 2100
126 Public Service constructive algorithms graphs trees Statement F VK Cup 2018 - Round 1 {923} PROGRAMMING VK Cup 2018 Round 1 and CF Round #470 (div. 1 & 2) editorial 2900
905 Dependency management *special graphs implementation Statement C VK Cup 2018 - Квалификация 1 {928} PROGRAMMING 2300
8369 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
644 A Colourful Prospect geometry graphs Statement C Codeforces Round 462 (Div. 1) {933} PROGRAMMING 57763 2400
3407 Sleepy Game dfs and similar dp games graphs Statement B Codeforces Round 467 (Div. 1) {936} PROGRAMMING Codeforces Round #467, Editorial 2100
6896 Buy a Ticket data structures graphs shortest paths Statement D Educational Codeforces Round 38 (Rated for Div. 2) {938} PROGRAMMING Educational Codeforces Round 38 — Editorial 2000
1082 Shortest Path Queries bitmasks data structures dsu graphs Statement G Educational Codeforces Round 38 (Rated for Div. 2) {938} PROGRAMMING Educational Codeforces Round 38 — Editorial 2900
8099 Love Rescue dfs and similar dsu graphs greedy strings Statement D Codeforces Round 464 (Div. 2) {939} PROGRAMMING Analysis of Codeforces Round #464 1600
29571 Love Triangle graphs Statement A Codeforces Round 464 (Div. 2) {939} PROGRAMMING Analysis of Codeforces Round #464 800
15285 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
2246 Data Center Maintenance dfs and similar graphs Statement C Codeforces Round 469 (Div. 1) {949} PROGRAMMING 58291 2000
7849 Fight Against Traffic dfs and similar graphs shortest paths Statement D Educational Codeforces Round 40 (Rated for Div. 2) {954} PROGRAMMING 58519 1600
744 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
3755 Mahmoud and Ehab and the xor-MST bitmasks dp graphs implementation math Statement E Codeforces Round 473 (Div. 2) {959} PROGRAMMING Codeforces round #473 editorial 1900
3376 Pathwalks data structures dp graphs Statement F 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 2000
1578 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
758 Degree Set constructive algorithms graphs implementation Statement D Educational Codeforces Round 43 (Rated for Div. 2) {976} PROGRAMMING 59195 2400
665 Minimal k-covering flows graphs Statement F Educational Codeforces Round 43 (Rated for Div. 2) {976} PROGRAMMING 59195 2500
25430 Cyclic Components dfs and similar dsu graphs Statement E Codeforces Round 479 (Div. 3) {977} PROGRAMMING Codeforces Round #479 (Div. 3) Editorial 1500
215 Cactus to Tree dp graphs trees Statement F Codeforces Round 480 (Div. 2) {980} PROGRAMMING Tutorial 2900
6841 Useful Decomposition implementation trees Statement C Avito Code Challenge 2018 {981} PROGRAMMING 59713 1400
15741 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
929 Elevator dp graphs shortest paths Statement C Codeforces Round 483 (Div. 1) [Thanks, Botan Investments and Victor Shaburov!] {983} PROGRAMMING Codeforces Round #483 [Thanks, Botan Investments and Victor Shaburov!] Editoral 2500
8291 Fair graphs greedy number theory shortest paths Statement A Codeforces Round 485 (Div. 1) {986} PROGRAMMING Codeforces Round #485 Editorial 1600
2708 AND Graph bitmasks dfs and similar dsu graphs Statement C Codeforces Round 485 (Div. 1) {986} PROGRAMMING Codeforces Round #485 Editorial 2300
739 Oppa Funcan Style Remastered graphs math number theory shortest paths Statement F Codeforces Round 485 (Div. 1) {986} PROGRAMMING Codeforces Round #485 Editorial 3200
4031 A Mist of Florescence constructive algorithms graphs Statement C Codeforces Round 487 (Div. 2) {989} PROGRAMMING Codeforces Round #487 (Div. 2) Editorial 1800
4108 Graph And Its Complement constructive algorithms graphs implementation Statement D Educational Codeforces Round 45 (Rated for Div. 2) {990} PROGRAMMING Educational Codeforces Round 45 Editorial 1700
925 Number Clicker divide and conquer graphs meet-in-the-middle number theory Statement E Codeforces Round 492 (Div. 1) [Thanks, uDebug!] {995} PROGRAMMING Editorial for Codeforces Round #492 [Thanks u-Debug!] 2700
514 Cycles in product combinatorics divide and conquer trees Statement D Codeforces Round 493 (Div. 1) {997} PROGRAMMING 60357 2800
7804 Reachability from the Capital dfs and similar graphs greedy Statement E Codeforces Round 490 (Div. 3) {999} PROGRAMMING 60138 1900
6460 We Need More Bosses dfs and similar graphs trees Statement E Educational Codeforces Round 46 (Rated for Div. 2) {1000} PROGRAMMING 60288 2100
3025 Tree Constructing constructive algorithms graphs Statement E Codeforces Round 494 (Div. 3) {1003} PROGRAMMING 60417 2200
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
11569 Military Problem dfs and similar graphs trees Statement E Codeforces Round 498 (Div. 3) {1006} PROGRAMMING 60672 1600
6625 Relatively Prime Graph brute force constructive algorithms graphs greedy math Statement D Educational Codeforces Round 47 (Rated for Div. 2) {1009} PROGRAMMING 60630 1700
1049 Allowed Letters bitmasks flows graph matchings graphs greedy Statement G Educational Codeforces Round 47 (Rated for Div. 2) {1009} PROGRAMMING 60630 2500
2560 Mars rover dfs and similar graphs implementation trees Statement D Codeforces Round 499 (Div. 1) {1010} PROGRAMMING 60851 2100
259 Tree fft graphs trees Statement F Codeforces Round 499 (Div. 1) {1010} PROGRAMMING 60851 3400
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
1387 Sergey's problem constructive algorithms graphs Statement C Codeforces Round 503 (by SIS, Div. 1) {1019} PROGRAMMING 61161 2800
24972 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
8342 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
3397 Tree with Small Distances dp graphs greedy Statement E Codeforces Round 506 (Div. 3) {1029} PROGRAMMING Codeforces Round #506 (Div. 3) Editorial 2200
310 Familiar Operations brute force graphs math Statement F Technocup 2019 - Elimination Round 2 {1031} PROGRAMMING Codeforces Round #517 and Technocup 2019 Elimination Round 2 Editorial 2700
15823 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
18975 Valid BFS? dfs and similar graphs shortest paths trees Statement D Manthan, Codefest 18 (rated, Div. 1 + Div. 2) {1037} PROGRAMMING Tutorial 1700
3123 Trips graphs Statement E Manthan, Codefest 18 (rated, Div. 1 + Div. 2) {1037} PROGRAMMING Tutorial 2100
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
3850 Tree Reconstruction constructive algorithms data structures graphs greedy Statement E Codeforces Round 509 (Div. 2) {1041} PROGRAMMING Codeforces Round #509 (Div. 2) Editorial 1900
1466 Leaf Sets data structures dfs and similar dsu graphs greedy sortings trees Statement F Codeforces Round 510 (Div. 2) {1042} PROGRAMMING Tutorial 2400
827 Hyperspace Highways dfs and similar graphs trees Statement C Bubble Cup 11 - Finals [Online Mirror, Div. 1] {1045} PROGRAMMING Tutorial (PDF) 2500
3723 The Shortest Statement graphs shortest paths trees Statement F Educational Codeforces Round 51 (Rated for Div. 2) {1051} PROGRAMMING Educational Codeforces Round 51 Editorial 2300
13407 Metro graphs Statement A Mail.Ru Cup 2018 Round 2 {1055} PROGRAMMING Mail.Ru Cup 2018 Round 2 — analysis 1000
2055 Lucky Days math number theory Statement C Mail.Ru Cup 2018 Round 2 {1055} PROGRAMMING Mail.Ru Cup 2018 Round 2 — analysis 1900
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
299 Take Metro brute force data structures graphs Statement G Mail.Ru Cup 2018 Round 3 {1056} PROGRAMMING Mail.Ru Cup 2018 Round 3 Editorial 2800
601 Politics flows graphs Statement E Codeforces Round 523 (Div. 2) {1061} PROGRAMMING Tutorial (en) 2800
4164 Fun with Integers dfs and similar graphs implementation math Statement D Codeforces Round 520 (Div. 2) {1062} PROGRAMMING Tutorial 1800
981 Upgrading Cities dfs and similar graphs Statement F Codeforces Round 520 (Div. 2) {1062} PROGRAMMING Tutorial 3000
9179 Labyrinth graphs shortest paths Statement B Codeforces Round 516 (Div. 1, by Moscow Team Olympiad) {1063} PROGRAMMING 1800
11578 Vasya and Isolated Vertices constructive algorithms graphs Statement B Educational Codeforces Round 52 (Rated for Div. 2) {1065} PROGRAMMING Educational Codeforces Round 52 Editorial 1300
2857 Multihedgehog dfs and similar graphs shortest paths Statement B Codeforces Round 518 (Div. 1) [Thanks, Mail.Ru!] {1067} PROGRAMMING Tutorial 2000
3344 Colored Rooks constructive algorithms graphs Statement C Codeforces Round 518 (Div. 2) [Thanks, Mail.Ru!] {1068} PROGRAMMING E 1700
2593 Find a Number dp graphs number theory shortest paths Statement A 2018-2019 ICPC, NEERC, Southern Subregional Contest (Online Mirror, ACM-ICPC Rules, Teams Preferred) {1070} PROGRAMMING Solution to problem M. Algoland and Berland of 2018-2019 ICPC, NEERC 2200
778 Privatization of Roads in Berland flows graphs Statement I 2018-2019 ICPC, NEERC, Southern Subregional Contest (Online Mirror, ACM-ICPC Rules, Teams Preferred) {1070} PROGRAMMING Solution to problem M. Algoland and Berland of 2018-2019 ICPC, NEERC 2600
5875 Edge Deletion graphs greedy shortest paths Statement D Educational Codeforces Round 54 (Rated for Div. 2) {1076} PROGRAMMING E 1800
4633 Maximum Distance dsu graphs shortest paths sortings Statement D Avito Cool Challenge 2018 {1081} PROGRAMMING 63888 1800
4079 Maximum Diameter Graph constructive algorithms graphs implementation Statement D Educational Codeforces Round 55 (Rated for Div. 2) {1082} PROGRAMMING 63544 1800
2668 Petya and Graph flows graphs Statement G Educational Codeforces Round 55 (Rated for Div. 2) {1082} PROGRAMMING 63544 2400
654 Minegraphed constructive algorithms graphs Statement M 2018-2019 ICPC, NEERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1089} PROGRAMMING 2600
111 Distance Sum graphs Statement D 2018-2019 ICPC, NEERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1089} PROGRAMMING 3400
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
249 Bimatching graphs Statement B 2018-2019 ICPC, NEERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1089} PROGRAMMING 3500