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3859 Exposition binary search data structures dsu trees two pointers Statement E Codeforces Beta Round 6 (Div. 2 Only) {6} PROGRAMMING Beta Round #6 - Разбор задач 1900
1160 Interestring graph and Apples dfs and similar dsu graphs Statement E Codeforces Beta Round 9 (Div. 2 Only) {9} PROGRAMMING Codeforces Beta Round #9 tutorial 2300
7894 Holes data structures dsu Statement E Codeforces Beta Round 13 {13} PROGRAMMING Codeforces Beta Round #13 editorial 2700
5986 Hierarchy dfs and similar dsu greedy shortest paths Statement B Codeforces Beta Round 17 {17} PROGRAMMING Codeforces Beta Round #17 Tutorial 1600
2496 Fairy dfs and similar divide and conquer dsu Statement E Codeforces Beta Round 19 {19} PROGRAMMING Code Force Beta Round 19 Solution 2800
15461 Roads not only in Berland dsu graphs trees Statement D Codeforces Beta Round 25 (Div. 2 Only) {25} PROGRAMMING Codeforces Beta Round #25 Solution Analysis 1900
3080 Ring Road 2 2-sat dfs and similar dsu graphs Statement D Codeforces Beta Round 27 (Codeforces format, Div. 2) {27} PROGRAMMING Solution of ABC @ Round#27 2300
5502 pSort dfs and similar dsu graphs Statement B Codeforces Beta Round 28 (Codeforces format) {28} PROGRAMMING Codeforces Beta Round #28 (Разбор задач A и B) 1600
612 Two Paths constructive algorithms dsu graphs implementation Statement E Codeforces Beta Round 36 {36} PROGRAMMING Codeforces Beta Round #36 (Problem E solution) 2500
318 School dp dsu Statement B School Team Contest 3 (Winter Computer School 2010/11) {45} PROGRAMMING 2400
358 Hercule Poirot Problem dsu graphs Statement F School Personal Contest #2 (Winter Computer School 2010/11) - Codeforces Beta Round 43 (ACM-ICPC Rules) {46} PROGRAMMING School Individual Contest #2 (WCS 2010/11) - Codeforces Beta Round #43 (ACM-ICPC Rules). Tasks B, D, E tutorial. 2300
5298 Serial Time! dfs and similar dsu Statement B Codeforces Beta Round 56 {60} PROGRAMMING Solutions for Codeforces Beta Round #56 1500
546 Savior brute force dsu math Statement D Codeforces Beta Round 56 {60} PROGRAMMING Solutions for Codeforces Beta Round #56 2400
1412 Chessboard Billiard dfs and similar dsu graphs number theory Statement C Codeforces Beta Round 68 {74} PROGRAMMING Solutions for Codeforces Beta Round #68 2100
2134 Gift dsu graphs sortings trees Statement A All-Ukrainian School Olympiad in Informatics {76} PROGRAMMING All-Ukrainian School Olympiad in Informatics: editorial (A,B,C,D,E,F) 2300
1170 Beavermuncher-0xFF dfs and similar dp dsu greedy trees Statement C Codeforces Beta Round 69 (Div. 1 Only) {77} PROGRAMMING Codeforces Beta Round #69 tutorial 2300
398 Pairs dfs and similar dp dsu graphs implementation trees Statement E Yandex.Algorithm Open 2011: Qualification 1 {81} PROGRAMMING 2600
1097 Guard Towers binary search dsu geometry graphs sortings Statement E Yandex.Algorithm 2011: Round 1 {85} PROGRAMMING Яндекс.Алгоритм 2011 - Раунд 1 (Разбор задачи Е "Сторожевые башни") 2600
1052 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
1010 Ski Base combinatorics dsu graphs Statement C Codeforces Beta Round 75 (Div. 1 Only) {91} PROGRAMMING Analysis Codeforces Beta Round #75 2500
1873 Lucky Country dp dsu graphs Statement E Codeforces Beta Round 77 (Div. 1 Only) {95} PROGRAMMING Codeforces Beta Round #77 - Analysis 2400
429 Leaders dfs and similar dsu graphs trees Statement E Yandex.Algorithm 2011: Finals {97} PROGRAMMING Финал Яндекс.Алгоритм: разбор A-B 2800
10549 Cthulhu dfs and similar dsu graphs Statement B Codeforces Beta Round 80 (Div. 1 Only) {103} PROGRAMMING Tutorial 1600
145 Entertaining Geodetics brute force dsu implementation Statement D Codeforces Beta Round 81 {105} PROGRAMMING Tutorial 2600
4088 Lucky Tree dp dsu trees Statement C Codeforces Beta Round 84 (Div. 1 Only) {109} PROGRAMMING Tutorial 2000
1581 Petya and Spiders bitmasks dp dsu Statement C Codeforces Beta Round 85 (Div. 1 Only) {111} PROGRAMMING Codeforces Beta Round #85: Разбор задач 2100
1358 Clearing Up constructive algorithms dp dsu graphs Statement E Codeforces Round 101 (Div. 2) {141} PROGRAMMING Codeforces Round #101 (Div. 2) Разбор Задач. 2600
3340 Edges in MST dfs and similar dsu graphs sortings Statement D Codeforces Round 111 (Div. 2) {160} PROGRAMMING Codeforces Round #111 (Div. 2) Разбор Задач 2500
1927 Beard Graph data structures dsu trees Statement D Codeforces Round 112 (Div. 2) {165} PROGRAMMING Codeforces Round #112 (Div. 2) Tutorial 2200
3002 Party brute force dfs and similar dsu graphs Statement C2 ABBYY Cup 2.0 - Easy {177} PROGRAMMING 1500
2989 Party dfs and similar dsu graphs Statement C1 ABBYY Cup 2.0 - Easy {177} PROGRAMMING 1500
1575 Weak Memory dfs and similar dsu Statement C Codeforces Round 119 (Div. 1) {187} PROGRAMMING Tutorial 2100
1730 Counter Attack data structures dsu graphs hashing sortings Statement E Codeforces Round 120 (Div. 2) {190} PROGRAMMING Codeforces Round #120 (Div.2) — editorial 2300
858 Building Forest data structures dsu graphs Statement E Codeforces Round 123 (Div. 2) {195} PROGRAMMING Codeforces Round #123 (Div. 2) Разбор Задач 2200
1202 Opening Portals dsu graphs shortest paths Statement E Codeforces Round 124 (Div. 1) {196} PROGRAMMING Codeforces Round #124 — editorial 2500
875 Trails and Glades constructive algorithms dsu graphs greedy Statement C VK Cup 2012 Finals, Practice Session {209} PROGRAMMING 2400
614 Cutting a Fence binary search data structures dsu Statement D VK Cup 2012 Finals (unofficial online-version) {212} PROGRAMMING 2400
24216 Ice Skating brute force dfs and similar dsu graphs Statement A Codeforces Round 134 (Div. 1) {217} PROGRAMMING Editorial for Codeforces Round #134 1400
353 Alien DNA data structures dsu trees Statement E Codeforces Round 134 (Div. 1) {217} PROGRAMMING Editorial for Codeforces Round #134 2700
2810 The Road to Berland is Paved With Good Intentions 2-sat dfs and similar dsu graphs Statement E Codeforces Round 141 (Div. 2) {228} PROGRAMMING Codeforces Round #141 (Div. 2) Tutorial 2000
1663 Black and White Tree constructive algorithms dsu graphs greedy trees Statement D Codeforces Round 158 (Div. 2) {260} PROGRAMMING Codeforces Round #158 (Div. 2) Tutorial 2200
21469 Learning Languages dfs and similar dsu Statement A Codeforces Round 170 (Div. 1) {277} PROGRAMMING Codeforces Round #170 Tutorial 1500
2763 Connected Components data structures dfs and similar dp dsu Statement D Croc Champ 2013 - Round 1 {292} PROGRAMMING Чемпионат КРОК 2013 — Раунд 1 (Разбор задач) 1900
599 Ilya and Two Numbers constructive algorithms data structures dsu greedy Statement E Codeforces Round 186 (Div. 2) {313} PROGRAMMING Tutorial 2300
940 The Red Button combinatorics dfs and similar dsu graphs greedy Statement E MemSQL start[c]up Round 1 {325} PROGRAMMING Editorial 2700
576 Reclamation dsu Statement D MemSQL start[c]up Round 1 {325} PROGRAMMING 2800
16705 Knight Tournament data structures dsu Statement A Codeforces Round 207 (Div. 1) {356} PROGRAMMING 9210 1700
432 Dima and Kicks brute force dsu graphs implementation Statement E Codeforces Round 208 (Div. 2) {358} PROGRAMMING Codeforces Round #208 (Div. 2) Разбор 2600
1019 Fools and Foolproof Roads data structures dfs and similar dsu graphs greedy Statement D Codeforces Round 212 (Div. 2) {362} PROGRAMMING Codeforces Round #212 (Div. 2). Tutorial. Part 1. 2500
1721 Dima and Trap Graph binary search data structures dfs and similar dsu shortest paths two pointers Statement D Codeforces Round 214 (Div. 2) {366} PROGRAMMING Codeforces Round #214 (Div. 2) — Tutorial 2400
6460 Vessels data structures dsu implementation trees Statement D Codeforces Round 218 (Div. 2) {371} PROGRAMMING Codeforces Round #218 (Div. 2): Tutorial 1900
206 Inna and Babies binary search data structures dsu geometry implementation Statement E Codeforces Round 220 (Div. 2) {374} PROGRAMMING Codeforces Round #220 (Div. 2) разбор 2600
3163 Dima and Bacteria dsu graphs shortest paths Statement D Codeforces Round 234 (Div. 2) {400} PROGRAMMING Codeforces Round #234 (Div. 2) — Tutorial 2000
9482 A + B Strikes Back *special brute force constructive algorithms dsu implementation Statement H April Fools Day Contest 2014 {409} PROGRAMMING April Fools Day Contest 2014: editorial 1700
1317 Nanami's Digital Board dsu implementation Statement D Codeforces Round 248 (Div. 2) {433} PROGRAMMING Codeforces Round #248 Editorial 2300
2882 Dungeons and Candies dsu graphs greedy trees Statement C Zepto Code Rush 2014 {436} PROGRAMMING Zepto Code Rush 2014 — solutions A-D 1800
3664 The Child and Zoo dsu sortings Statement D Codeforces Round 250 (Div. 2) {437} PROGRAMMING 12513 2100
1197 Valera and Swaps constructive algorithms dsu graphs implementation math string suffix structures Statement D Codeforces Round 252 (Div. 2) {441} PROGRAMMING Разбор Codeforces Round #252 (Div. 2) 2300
856 DZY Loves Planting binary search dsu trees Statement E Codeforces Round 254 (Div. 1) {444} PROGRAMMING Codeforces Round #254 Editorial 2600
14652 DZY Loves Chemistry dfs and similar dsu greedy Statement B Codeforces Round 254 (Div. 2) {445} PROGRAMMING Codeforces Round #254 Editorial 1500
1195 Three strings data structures dsu string suffix structures strings Statement E MemSQL Start[c]UP 2.0 - Round 1 {452} PROGRAMMING MemSQL Start[c]UP 2.0 Round 1 and 2 Editorials 2400
6452 Civilization dfs and similar dp dsu ternary search trees Statement C Codeforces Round 260 (Div. 1) {455} PROGRAMMING Codeforces Round #260 — Editorial 2200
401 Appleman and Complicated Task dsu math Statement D Codeforces Round 263 (Div. 1) {461} PROGRAMMING Tutorial 2700
2612 Information Graph dfs and similar dsu graphs trees Statement E Codeforces Round 266 (Div. 2) {466} PROGRAMMING Editorial Codeforces Round #266 (Div. 2) 2400
5233 Two Sets 2-sat dfs and similar dsu graph matchings greedy Statement B Codeforces Round 268 (Div. 1) {468} PROGRAMMING 13896 2000
88 MUH and Lots and Lots of Segments data structures dsu Statement E Codeforces Round 269 (Div. 2) {471} PROGRAMMING Codeforces Round #269 Editorial 2700
6491 Design Tutorial: Inverse the Problem dfs and similar dsu shortest paths trees Statement D Codeforces Round 270 {472} PROGRAMMING Editorial 1900
6419 Queue dsu implementation Statement B Codeforces Round 279 (Div. 2) {490} PROGRAMMING Codeforces Round #279 (Div. 2) Editorial 1500
9585 New Year Permutation dfs and similar dsu graphs greedy math sortings Statement B Good Bye 2014 {500} PROGRAMMING Tutorial 2 1600
1578 New Year Domino data structures dp dsu Statement E Good Bye 2014 {500} PROGRAMMING Tutorial 2 2200
19304 Misha and Changing Handles data structures dsu strings Statement B Codeforces Round 285 (Div. 2) {501} PROGRAMMING Tutorial 1100
14876 Mr. Kitayuta's Colorful Graph dfs and similar dp dsu graphs Statement B Codeforces Round 286 (Div. 2) {505} PROGRAMMING Tutorial 1500
2527 Mr. Kitayuta's Colorful Graph brute force dfs and similar dsu graphs Statement D Codeforces Round 286 (Div. 1) {506} PROGRAMMING Editorial 2300
7761 Drazil and His Happy Friends brute force dsu meet-in-the-middle number theory Statement B Codeforces Round 292 (Div. 2) {515} PROGRAMMING Codeforces Round #292 Editorial 1400
1523 Drazil and Morning Exercise dfs and similar dp dsu trees two pointers Statement D Codeforces Round 292 (Div. 1) {516} PROGRAMMING 16468 2800
10822 Mike and Feet binary search data structures dp dsu Statement B Codeforces Round 305 (Div. 1) {547} PROGRAMMING Codeforces Round #305 Editorial 2100
1963 Love Triangles dfs and similar dsu graphs Statement C Codeforces Round 309 (Div. 1) {553} PROGRAMMING Codeforces Round #309 Editorial 2300
3912 Restructuring Company data structures dsu Statement D VK Cup 2015 - Finals, online mirror {566} PROGRAMMING Editorial for VK Cup 2015 — Finals 1900
807 Campus binary search data structures dsu trees Statement D Codeforces Round 317 [AimFund Thanks-Round] (Div. 1) {571} PROGRAMMING Codeforces Round #317 [AimFund Thanks-Round] Editorial 3000
18204 Lomsat gelral data structures dfs and similar dsu trees Statement E Educational Codeforces Round 2 {600} PROGRAMMING Editorial 2300
1244 Acyclic Organic Compounds data structures dfs and similar dsu hashing strings trees Statement D Codeforces Round 333 (Div. 1) {601} PROGRAMMING Codeforces Round #333 — editorial 2400
2710 Moodular Arithmetic combinatorics dfs and similar dsu math number theory Statement B Codeforces Round 334 (Div. 1) {603} PROGRAMMING Codeforces Round #334 Editorial 2000
1539 Pastoral Oddities data structures divide and conquer dsu math trees Statement E Codeforces Round 334 (Div. 1) {603} PROGRAMMING Codeforces Round #334 Bonus Editorial: More Ideas on Div. 1 E 2900
10199 Minimum spanning tree for each edge data structures dfs and similar dsu graphs trees Statement E Educational Codeforces Round 3 {609} PROGRAMMING Editorial 2100
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
2174 Table Compression dfs and similar dp dsu graphs greedy Statement C Codeforces Round 345 (Div. 1) {650} PROGRAMMING Codeforces Round #345: editorial 2300
678 Clockwork Bomb data structures dfs and similar dsu greedy trees Statement E Codeforces Round 345 (Div. 1) {650} PROGRAMMING Codeforces Round #345: editorial 3100
2842 Pursuit For Artifacts dfs and similar dsu graphs trees Statement E Educational Codeforces Round 10 {652} PROGRAMMING Editorial of Educational Codeforces Round 10 2300
1736 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
7984 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
1952 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
3460 Correct Bracket Sequence Editor data structures dsu strings Statement E Codeforces Round 350 (Div. 2) {670} PROGRAMMING Codeforces Round #350 (Div.2) Editorial 1700
1263 Bear and Square Grid dfs and similar dsu implementation Statement C Codeforces Round 356 (Div. 1) {679} PROGRAMMING Codeforces Round #356 — Editorial 2500
1047 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
6481 Swaps in Permutation dfs and similar dsu math Statement D Educational Codeforces Round 14 {691} PROGRAMMING Editorial of Educational Codeforces Round 14 1700
628 ...Wait for it... data structures dsu trees Statement E Codeforces Round 362 (Div. 1) {696} PROGRAMMING Codeforces Round #362 (Editorial) 2900
6172 Fix a Tree constructive algorithms dfs and similar dsu graphs trees Statement B Codeforces Round 363 (Div. 1) {698} PROGRAMMING 46148 1700
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
11432 Destroying Array data structures dsu Statement C Intel Code Challenge Elimination Round (Div. 1 + Div. 2, combined) {722} PROGRAMMING Tutorial 1600
7493 Lakes in Berland dfs and similar dsu graphs greedy implementation Statement D Codeforces Round 375 (Div. 2) {723} PROGRAMMING 1600
1744 st-Spanning Tree dsu graphs greedy implementation Statement F Codeforces Round 375 (Div. 2) {723} PROGRAMMING Codeforces Round #375 (Div.2) Editorial 2200
7789 Socks dfs and similar dsu graphs greedy Statement C Codeforces Round 376 (Div. 2) {731} PROGRAMMING 47840 1600
1296 Drivers Dissatisfaction data structures dsu graphs trees Statement F Codeforces Round 378 (Div. 2) {733} PROGRAMMING Codeforces Round #378 (Div. 2) editorial 2500
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
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
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
551 Timofey and our friends animals data structures divide and conquer dsu Statement E Codeforces Round 395 (Div. 1) {763} PROGRAMMING Codeforces Round #395 [Editorial] 2800
2600 Artsem and Saunders constructive algorithms dsu math Statement D Codeforces Round 397 by Kaspersky Lab and Barcelona Bootcamp (Div. 1 + Div. 2 combined) {765} PROGRAMMING Codeforces Round #397 Editorial 1700
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
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
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
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
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
977 Vladik and Entertaining Flags data structures dsu graphs Statement E Codeforces Round 416 (Div. 2) {811} PROGRAMMING Editorial 2600
1697 Bipartite Checking data structures dsu graphs Statement F Educational Codeforces Round 22 {813} PROGRAMMING 52410 2600
6221 Imbalanced Array data structures divide and conquer dsu sortings Statement D Educational Codeforces Round 23 {817} PROGRAMMING 52638 2000
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
2112 Desk Disorder combinatorics dfs and similar dsu graphs trees Statement E MemSQL Start[c]UP 3.0 - Round 1 {859} PROGRAMMING Tutorial 2100
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
1850 Forbidden Indices dsu string suffix structures strings Statement F Educational Codeforces Round 30 {873} PROGRAMMING 55171 2300
5390 Sorting the Coins dsu implementation sortings two pointers Statement B Codeforces Round 441 (Div. 1, by Moscow Team Olympiad) {875} PROGRAMMING Codeforces Round #441. Editorial. 1500
1583 Royal Questions dsu graphs greedy Statement F Codeforces Round 441 (Div. 1, by Moscow Team Olympiad) {875} PROGRAMMING Codeforces Round #441. Editorial. 2500
768 Binary Matrix dsu Statement E Educational Codeforces Round 31 {884} PROGRAMMING 55470 2500
5671 Petya and Catacombs dsu greedy implementation trees Statement C Технокубок 2018 - Отборочный Раунд 3 {886} PROGRAMMING Editorial Codeforces Round 445 (and Technocup 2018 — Elimination Round 3) 1300
2980 Envy data structures dsu graphs Statement C Codeforces Round 446 (Div. 1) {891} PROGRAMMING Codeforces Round #446 Editorial 2500
2501 Welcome home, Chtholly data structures dsu Statement E Codeforces Round 449 (Div. 1) {896} PROGRAMMING Codeforces Round #449 Editorial 3100
3512 Segments Removal data structures dsu flows implementation two pointers Statement E Codeforces Round 452 (Div. 2) {899} PROGRAMMING Codeforces Round #452 (Div.2) Editorial 2100
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
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
3036 Imbalance Value of a Tree data structures dsu graphs trees Statement F Educational Codeforces Round 36 (Rated for Div. 2) {915} PROGRAMMING 57123 2500
8530 SUM and REPLACE brute force data structures dsu number theory Statement F Educational Codeforces Round 37 (Rated for Div. 2) {920} PROGRAMMING T 2000
7683 Connected Components? data structures dfs and similar dsu graphs Statement E Educational Codeforces Round 37 (Rated for Div. 2) {920} PROGRAMMING T 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
1083 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
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
10527 Mahmoud and Ehab and the message dsu greedy implementation Statement B Codeforces Round 473 (Div. 2) {959} PROGRAMMING Codeforces round #473 editorial 1300
207 Visible Black Areas data structures dsu geometry trees Statement G Educational Codeforces Round 42 (Rated for Div. 2) {962} PROGRAMMING Educational Codeforces Round 42 Editorial 2900
25449 Cyclic Components dfs and similar dsu graphs Statement E Codeforces Round 479 (Div. 3) {977} PROGRAMMING Codeforces Round #479 (Div. 3) Editorial 1500
2172 Kuro and GCD and XOR and SUM binary search bitmasks brute force data structures dp dsu greedy math number theory strings trees Statement D Codeforces Round 482 (Div. 2) {979} PROGRAMMING 1750.0 Codeforces Round #482 (Div. 2) Editorial 2200
2511 Shark brute force data structures dsu trees Statement D Codeforces Round 484 (Div. 2) {982} PROGRAMMING Editorial 1900
2710 AND Graph bitmasks dfs and similar dsu graphs Statement C Codeforces Round 485 (Div. 1) {986} PROGRAMMING Codeforces Round #485 Editorial 2300
2297 GCD Counting divide and conquer dp dsu number theory trees Statement G Educational Codeforces Round 45 (Rated for Div. 2) {990} PROGRAMMING Educational Codeforces Round 45 Editorial 2400
7686 Dominant Indices data structures dsu trees Statement F Educational Codeforces Round 47 (Rated for Div. 2) {1009} PROGRAMMING 60630 2300
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
396 Cycle sort dsu math Statement E Codeforces Round 500 (Div. 1) [based on EJOI] {1012} PROGRAMMING 60920 3100
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
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
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
1183 Deduction Queries data structures dsu Statement D Lyft Level 5 Challenge 2018 - Final Round {1044} PROGRAMMING Lyft Level 5 Challenge 2018 — Final Round — Editorial 2600
480 Distinctification data structures dsu greedy Statement G Educational Codeforces Round 51 (Rated for Div. 2) {1051} PROGRAMMING Educational Codeforces Round 51 Editorial 2700
5535 Alice and Hairdresser dsu implementation Statement B Mail.Ru Cup 2018 Round 2 {1055} PROGRAMMING Mail.Ru Cup 2018 Round 2 — analysis 1300
4634 Maximum Distance dsu graphs shortest paths sortings Statement D Avito Cool Challenge 2018 {1081} PROGRAMMING 63888 1800
7440 Make It Connected dsu graphs greedy Statement F Codeforces Round 529 (Div. 3) {1095} PROGRAMMING Codeforces Round #529 (Div. 3) Editorial 2000
1240 Vasya and Maximum Profit binary search constructive algorithms data structures dp dsu Statement G Educational Codeforces Round 59 (Rated for Div. 2) {1107} PROGRAMMING Educational Codeforces Round 59 Editorial 2400
3542 MST Unification binary search dsu graphs greedy Statement F Codeforces Round 535 (Div. 3) {1108} PROGRAMMING 64751 2300
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
7731 Asya And Kittens constructive algorithms dsu Statement F Codeforces Round 541 (Div. 2) {1131} PROGRAMMING Codeforces Round #541 Editorial 1700
3618 Gourmet choice dfs and similar dp dsu graphs greedy Statement D Codeforces Round 541 (Div. 2) {1131} PROGRAMMING Codeforces Round #541 Editorial 2000
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
1546 Extending Set of Points data structures divide and conquer dsu Statement F Educational Codeforces Round 62 (Rated for Div. 2) {1140} PROGRAMMING Educational Codeforces Round 62 Editorial 2700
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
4004 Special Segments of Permutation data structures divide and conquer dsu two pointers Statement E Educational Codeforces Round 64 (Rated for Div. 2) {1156} PROGRAMMING 66827 2400
811 Vicky's Delivery Service data structures dsu graphs hashing Statement F Codeforces Round 561 (Div. 2) {1166} PROGRAMMING Codeforces Round #561 (Div. 2) Editorial 2800
25784 News Distribution dfs and similar dsu graphs Statement C Educational Codeforces Round 65 (Rated for Div. 2) {1167} PROGRAMMING 67058 1400
13502 Cover it! dfs and similar dsu graphs shortest paths trees Statement E Codeforces Round 565 (Div. 3) {1176} PROGRAMMING 67598 1700
665 Daleks' Invasion (hard) data structures dsu graphs trees Statement E3 Helvetic Coding Contest 2019 online mirror (teams allowed, unrated) {1184} PROGRAMMING helvetic-coding-contest-2019-editorial.pdf 2500
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
3934 Into Blocks (easy version) data structures dsu greedy implementation two pointers Statement G1 Codeforces Round 584 - Dasha Code Championship - Elimination Round (rated, open for everyone, Div. 1 + Div. 2) {1209} PROGRAMMING 69791 2000
9447 Path Queries divide and conquer dsu graphs sortings trees Statement G Codeforces Round 582 (Div. 3) {1213} PROGRAMMING Codeforces Round #582 (Div. 3) Editorial 2000
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
716 Forced Online Queries Problem data structures divide and conquer dsu graphs trees Statement F Educational Codeforces Round 72 (Rated for Div. 2) {1217} PROGRAMMING Educational Codeforces Round 72 Editorial 2800
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
730 Alice and the Unfair Game binary search data structures dp dsu Statement E Codeforces Round 593 (Div. 2) {1236} PROGRAMMING 70654 2600
9213 0-1 MST dfs and similar dsu graphs sortings Statement B Codeforces Round 599 (Div. 1) {1242} PROGRAMMING Codeforces Round #599 Editorial 1900
9533 Shichikuji and Power Grid dsu graphs greedy shortest paths trees Statement D Codeforces Round 597 (Div. 2) {1245} PROGRAMMING Codeforces Round #597 (Div. 2) Editorial 1900
22254 Books Exchange (easy version) dsu math Statement B1 Codeforces Round 595 (Div. 3) {1249} PROGRAMMING Codeforces Round #595 (Div. 3) Editorial 1000
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
10229 Harmonious Graph constructive algorithms dfs and similar dsu graphs greedy sortings Statement D Codeforces Round 600 (Div. 2) {1253} PROGRAMMING Editorial 1700
2244 Cheap Robot binary search dsu graphs shortest paths trees Statement F Codeforces Round 600 (Div. 2) {1253} PROGRAMMING Editorial 2600
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
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
4321 Segment Tree data structures dsu graphs trees Statement D Educational Codeforces Round 78 (Rated for Div. 2) {1278} PROGRAMMING Educational Codeforces Round 78 Editorial 2100
2005 Prefix Enlightenment dfs and similar dsu graphs Statement C Codeforces Round 616 (Div. 1) {1290} PROGRAMMING 1750.0 Codeforces Round #616 Editorial 2400
13846 NEKO's Maze Game data structures dsu implementation Statement A Codeforces Round 614 (Div. 1) {1292} PROGRAMMING 500.0 Codeforces Round #614 Editorial 1400
614 Number of Components dsu implementation Statement F Educational Codeforces Round 82 (Rated for Div. 2) {1303} PROGRAMMING Educational Codeforces Round 82 2800
1372 Kuroni and Antihype bitmasks dp dsu graphs Statement G Ozon Tech Challenge 2020 (Div.1 + Div.2, Rated, T-shirts + prizes!) {1305} PROGRAMMING 3250.0 Ozon Tech Challenge 2020 Editorial 3300
675 Cow and Vacation dfs and similar dsu trees Statement F Codeforces Round 621 (Div. 1 + Div. 2) {1307} PROGRAMMING 3000.0 Codeforces Round #621 (Div. 1 + Div. 2) Editorial 3200
20766 K-Complete Word dfs and similar dsu greedy implementation strings Statement C Codeforces Round 630 (Div. 2) {1332} PROGRAMMING 1250.0 Codeforces Round #630 Editorial 1500
2412 Robots on a Grid data structures dfs and similar dsu graphs greedy matrices Statement F Codeforces Round 634 (Div. 3) {1335} PROGRAMMING 75993 2600
6348 Monopole Magnets constructive algorithms dfs and similar dsu graphs Statement B Codeforces Round 639 (Div. 1) {1344} PROGRAMMING 1000.0 Codeforces Round #639 Editorial 2000
1831 Johnny and Megan's Necklace binary search bitmasks constructive algorithms dfs and similar dsu graphs Statement C Codeforces Round 647 (Div. 1) - Thanks, Algo Muse! {1361} PROGRAMMING 2000.0 Codeforces Round #647 Editorial 2500
7486 Tree Shuffling dfs and similar dp dsu greedy trees Statement E Codeforces Round 646 (Div. 2) {1363} PROGRAMMING 2250.0 78202 2000
20700 Solve The Maze constructive algorithms dfs and similar dsu graphs greedy implementation shortest paths Statement D Codeforces Round 648 (Div. 2) {1365} PROGRAMMING 1500.0 Editorial — Codeforces Round #648 1700
14250 Palindromic Paths dsu greedy math Statement C Educational Codeforces Round 89 (Rated for Div. 2) {1366} PROGRAMMING Educational Codeforces Round 89 Editorial
2407 Merging Towers data structures dsu implementation trees Statement E Educational Codeforces Round 91 (Rated for Div. 2) {1380} PROGRAMMING Educational Codeforces Round 91 Editorial
11246 String Transformation 1 dsu graphs greedy sortings strings trees Statement A Codeforces Round 659 (Div. 1) {1383} PROGRAMMING 1000.0 Codeforces Round #659 Editorial
1809 Columns Swaps 2-sat dfs and similar dsu graphs implementation Statement G Codeforces Round 656 (Div. 3) {1385} PROGRAMMING Codeforces Round #656 (Div. 3) Editorial 2300
655 Joker *special bitmasks data structures divide and conquer dsu Statement C Baltic Olympiad in Informatics 2020, Day 1 (IOI, Unofficial Mirror Contest, Unrated) {1386} PROGRAMMING T
1384 Controversial Rounds binary search data structures dp dsu two pointers Statement F Educational Codeforces Round 93 (Rated for Div. 2) {1398} PROGRAMMING Educational Codeforces Round 93 Editorial
1350 Fancy Fence *special data structures dp dsu math sortings Statement A Central-European Olympiad in Informatics, CEOI 2020, Day 1 (IOI, Unofficial Mirror Contest, Unrated) {1402} PROGRAMMING Editorial
1293 Clusterization Counting combinatorics dp dsu fft graphs Statement G Grakn Forces 2020 {1408} PROGRAMMING 3000.0 Grakn Forces -- Editorial
2177 Avoid Rainbow Cycles dsu graphs greedy sortings Statement E Grakn Forces 2020 {1408} PROGRAMMING 2500.0 Grakn Forces -- Editorial
8568 Peaceful Rooks dfs and similar dsu graphs Statement C Technocup 2021 - Elimination Round 3 {1411} PROGRAMMING 1750.0 Technocup 2021 Elimination Round 3 and Round #692 (Div. 1 + Div. 2) Editorial
2697 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
561 Rain of Fire binary search dfs and similar dsu graphs implementation sortings Statement F Codeforces Round 671 (Div. 2) {1419} PROGRAMMING 3000.0 Codeforces Round #671 Editorial
625 Virus data structures dsu graphs Statement H Bubble Cup 13 - Finals [Online Mirror, unrated, Div. 1] {1423} PROGRAMMING FinalsEditorial2020.pdf
5241 Identify the Operations brute force combinatorics data structures dsu greedy implementation Statement B Codeforces Round 681 (Div. 1, based on VK Cup 2019-2020 - Final) {1442} PROGRAMMING 1000.0 84298
1851 Team-Building 2-sat dfs and similar dsu graphs Statement C Codeforces Round 680 (Div. 1, based on Moscow Team Olympiad) {1444} PROGRAMMING 1500.0 Codeforces Round #680 Editorial
6601 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
1729 Plan of Lectures dfs and similar dsu graphs Statement E Educational Codeforces Round 100 (Rated for Div. 2) {1463} PROGRAMMING Educational Codeforces Round 100 Editorial
3057 Euclid's nightmare dfs and similar dsu graphs math Statement F Good Bye 2020 {1466} PROGRAMMING 1750.0 Good Bye 2020 Editorial
241 Bakery data structures dsu Statement B 2020-2021 ICPC, NERC, Southern and Volga Russian Regional Contest (Online Mirror, ICPC Rules) {1468} PROGRAMMING Tutorial (PDF)
5862 Road Reform dsu graphs greedy Statement J 2020-2021 ICPC, NERC, Southern and Volga Russian Regional Contest (Online Mirror, ICPC Rules) {1468} PROGRAMMING 2020-2021 ICPC, NERC, Southern and Volga Russian Regional Contest (Online Mirror, ICPC Rules) — Tutorials
4178 Strange Housing constructive algorithms dfs and similar dsu graph matchings graphs Statement D Codeforces Round 694 (Div. 1) {1470} PROGRAMMING 1500.0 86464
9222 Journey dfs and similar dp dsu implementation two pointers Statement D Educational Codeforces Round 103 (Rated for Div. 2) {1476} PROGRAMMING 87356
4113 Playlist data structures dsu implementation Statement D Технокубок 2021 - Финал {1482} PROGRAMMING 2000.0 Technocup 2021: Final Round and Codeforces Round #709 — tutorial
1353 Playlist data structures dsu implementation two pointers Statement B Codeforces Round 709 (Div. 1, based on Technocup 2021 Final Round) {1483} PROGRAMMING 1000.0 Technocup 2021: Final Round and Codeforces Round #709 — tutorial
2816 Dogeforces brute force constructive algorithms divide and conquer dsu greedy implementation trees Statement D Educational Codeforces Round 105 (Rated for Div. 2) {1494} PROGRAMMING Educational Codeforces Round 105 Editorial
24671 GCD Sum brute force math Statement A CodeCraft-21 and Codeforces Round 711 (Div. 2) {1498} PROGRAMMING 500.0 CodeCraft-21 and Codeforces Round #711 (Div. 2) Editorial
1255 Flip the Cards 2-sat constructive algorithms data structures dsu greedy sortings Statement D Codeforces Round 712 (Div. 1) {1503} PROGRAMMING 1750.0 T 2600
14177 Restoring the Permutation constructive algorithms data structures dsu greedy Statement E Codeforces Round 710 (Div. 3) {1506} PROGRAMMING Editorial
1723 Complete the MST data structures dfs and similar dsu graphs greedy math Statement C Codeforces Round 715 (Div. 1) {1508} PROGRAMMING 1500.0 Codeforces Round #715 Editorial
6451 GCD and MST constructive algorithms data structures dsu graphs implementation number theory sortings Statement D Divide by Zero 2021 and Codeforces Round 714 (Div. 2) {1513} PROGRAMMING 2000.0 Divide by Zero 2021 and Codeforces Round #714 (Div. 2) Editorial
2070 Phoenix and Earthquake constructive algorithms dfs and similar dsu graphs greedy trees Statement F Codeforces Global Round 14 {1515} PROGRAMMING 3250.0 Editorial
13770 Little Alawn's Puzzle combinatorics dfs and similar dp dsu graphs math Statement C Codeforces LATOKEN Round 1 (Div. 1 + Div. 2) {1534} PROGRAMMING 1250.0 Codeforces LATOKEN Round 1 (Div. 1 + Div. 2) Editorial
2805 Figure Fixing constructive algorithms dfs and similar dsu graphs math Statement F Codeforces Round 726 (Div. 2) {1537} PROGRAMMING 2000.0 Codeforces Round #726 (Div.2) Editorial
895 Jumping Around data structures divide and conquer dp dsu graphs shortest paths trees Statement F Educational Codeforces Round 111 (Rated for Div. 2) {1550} PROGRAMMING Educational Codeforces Round 111 Editorial
1211 Common Divisor Graph binary search dsu graphs math number theory Statement G Harbour.Space Scholarship Contest 2021-2022 (open for everyone, rated, Div. 1 + Div. 2) {1553} PROGRAMMING 3000.0 Harbour.Space Scholarship Contest 2021-2022 (Div. 1 + Div. 2) Editorial
1044 Good Graph data structures dsu graphs trees Statement F Educational Codeforces Round 112 (Rated for Div. 2) {1555} PROGRAMMING 93389 2700
15976 Mocha and Diana (Easy Version) brute force constructive algorithms dsu graphs greedy trees Statement D1 Codeforces Round 738 (Div. 2) {1559} PROGRAMMING 1500.0 Tutorial (en) 1400
3049 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
740 Occurrences combinatorics dp dsu fft graphs Statement F Educational Codeforces Round 114 (Rated for Div. 2) {1574} PROGRAMMING 95188
4254 Jeopardy of Dropped Balls brute force dsu implementation Statement J COMPFEST 13 - Finals Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1575} PROGRAMMING COMPFEST 13 — Editorial
1431 Labyrinth binary search dsu Statement L ICPC WF Moscow Invitational Contest - Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1578} PROGRAMMING Tutorial (PDF)
473 Building Forest Trails data structures dsu Statement B ICPC WF Moscow Invitational Contest - Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1578} PROGRAMMING Tutorial (PDF)
17074 Hemose Shopping dsu math sortings Statement B Codeforces Round 746 (Div. 2) {1592} PROGRAMMING 1000.0 95583
9328 The Number of Imposters constructive algorithms dfs and similar dp dsu graphs Statement D Codeforces Round 747 (Div. 2) {1594} PROGRAMMING 1750.0 95525 1700
661 Tree Queries binary search data structures dp dsu geometry trees Statement F Educational Codeforces Round 116 (Rated for Div. 2) {1606} PROGRAMMING 96454
8374 Social Network dsu graphs greedy implementation trees Statement D Deltix Round, Autumn 2021 (open for everyone, rated, Div. 1 + Div. 2) {1609} PROGRAMMING 2000.0 Deltix Round, Autumn 2021. Editorial 1600
1923 Trader Problem binary search data structures dsu greedy math sortings Statement G Codeforces Round 760 (Div. 3) {1618} PROGRAMMING Codeforces Round #760 (Div. 3) Editorial
2725 Unusual Minesweeper binary search dfs and similar dsu implementation sortings Statement G Codeforces Round 762 (Div. 3) {1619} PROGRAMMING Tutorial
9623 Replace the Numbers data structures dsu greedy trees Statement E Educational Codeforces Round 119 (Rated for Div. 2) {1620} PROGRAMMING 98061
7570 MinOr Tree bitmasks dfs and similar dsu greedy Statement G Codeforces Round 764 (Div. 3) {1624} PROGRAMMING Codeforces Round #764 (Div. 3) Editorial
1737 Spanning Tree Queries binary search data structures dsu graphs implementation math sortings Statement E Educational Codeforces Round 122 (Rated for Div. 2) {1633} PROGRAMMING 99539
2722 Cars constructive algorithms dfs and similar dsu graphs greedy sortings Statement E Codeforces Round 772 (Div. 2) {1635} PROGRAMMING 2250.0 Codeforces Round #772 Editorial