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3858 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
2139 Old Berland Language data structures greedy trees Statement C Codeforces Beta Round 37 {37} PROGRAMMING Codeforces Beta Round #37 (Tutorial) 1900
15035 Enemy is weak data structures trees Statement E Codeforces Beta Round 57 (Div. 2) {61} PROGRAMMING Round 57-A 2100
2047 Big Maximum Sum data structures dp greedy implementation math trees Statement D Codeforces Beta Round 67 (Div. 2) {75} PROGRAMMING Codeforces Beta Round #67 (Div. 2) Editorial 2100
414 Tree or not Tree data structures divide and conquer implementation trees Statement E Codeforces Beta Round 88 {117} PROGRAMMING Codeforces Beta Round #88 (Editorial) 2800
960 Mushroom Gnomes - 2 binary search data structures probabilities sortings Statement C Codeforces Beta Round 99 (Div. 1) {138} PROGRAMMING Codeforces Beta Round #99: editorial 2500
1034 Freezing with Style binary search data structures divide and conquer trees Statement E Codeforces Round 107 (Div. 1) {150} PROGRAMMING Tutorial 3000
2164 e-Government data structures dfs and similar dp strings trees Statement E VK Cup 2012 Round 2 {163} PROGRAMMING VK Cup 2012 Round 2 — Разбор 2800
1926 Beard Graph data structures dsu trees Statement D Codeforces Round 112 (Div. 2) {165} PROGRAMMING Codeforces Round #112 (Div. 2) Tutorial 2200
1511 Archaeology data structures dfs and similar trees Statement E Croc Champ 2012 - Round 2 {176} PROGRAMMING Croc Champ 2012 — Round 2 — Editorial 3000
9158 Fools and Roads data structures dfs and similar trees Statement C Codeforces Round 121 (Div. 1) {191} PROGRAMMING Разбор Codeforces Round #121 2100
956 Thwarting Demonstrations binary search data structures trees Statement E Codeforces Round 121 (Div. 1) {191} PROGRAMMING Разбор Codeforces Round #121 2200
8832 Blood Cousins binary search data structures dfs and similar trees Statement E Codeforces Round 130 (Div. 2) {208} PROGRAMMING 4930 2400
353 Alien DNA data structures dsu trees Statement E Codeforces Round 134 (Div. 1) {217} PROGRAMMING Editorial for Codeforces Round #134 2700
544 Noble Knight's Path data structures trees Statement E Codeforces Round 140 (Div. 1) {226} PROGRAMMING Codeforces Round #140 Editorial 2900
2310 Cactus data structures dfs and similar dp graphs trees Statement E Codeforces Round 143 (Div. 2) {231} PROGRAMMING Tutorial Codeforces Round #143 2400
1313 Little Elephant and Tree data structures dfs and similar trees Statement E Codeforces Round 157 (Div. 1) {258} PROGRAMMING Codeforces Round #157 — Editorial 2400
469 Roadside Trees data structures dp Statement E Codeforces Round 162 (Div. 1) {264} PROGRAMMING Tutorial 2900
1850 Little Girl and Problem on Trees data structures graphs trees Statement E Codeforces Round 169 (Div. 2) {276} PROGRAMMING Codeforces Round #169 — Unofficial Editorial 2300
4294 Sausage Maximization bitmasks data structures trees Statement E Codeforces Round 173 (Div. 2) {282} PROGRAMMING Round #173 — Editorial 2100
1963 Close Vertices data structures divide and conquer trees Statement E Croc Champ 2013 - Round 2 {293} PROGRAMMING Croc Champ 2013 — Round 2 — Editorial 2700
1542 Oh Sweet Beaverette data structures sortings Statement A2 ABBYY Cup 3.0 - Finals (online version) {331} PROGRAMMING ABBYY Cup 3.0 — Finals. Solutions 1600
202 Escaping on Beaveractor data structures implementation trees Statement D3 ABBYY Cup 3.0 - Finals (online version) {331} PROGRAMMING ABBYY Cup 3.0 — Finals. Solutions 2900
32362 Xenia and Bit Operations data structures trees Statement D Codeforces Round 197 (Div. 2) {339} PROGRAMMING Codeforces Round #197 — Tutorial 1700
10765 Xenia and Tree data structures divide and conquer trees Statement E Codeforces Round 199 (Div. 2) {342} PROGRAMMING Tutorial 2200
6811 Water Tree data structures dfs and similar graphs trees Statement D Codeforces Round 200 (Div. 1) {343} PROGRAMMING Codeforces Round #200 Tutorial 2100
6458 Vessels data structures dsu implementation trees Statement D Codeforces Round 218 (Div. 2) {371} PROGRAMMING Codeforces Round #218 (Div. 2): Tutorial 1900
1127 Choosing Subtree is Fun binary search data structures dfs and similar trees two pointers Statement D Codeforces Round 219 (Div. 1) {372} PROGRAMMING 9944 2600
987 Inna and Sequence binary search data structures dp trees Statement D Codeforces Round 220 (Div. 2) {374} PROGRAMMING Codeforces Round #220 (Div. 2) разбор 2300
8850 Tree and Queries data structures dfs and similar trees Statement D Codeforces Round 221 (Div. 1) {375} PROGRAMMING Codeforces Round #221 Tutorial 2400
2737 New Year Tree data structures divide and conquer trees Statement F Good Bye 2013 {379} PROGRAMMING Tutorial Good Bye 2013 2400
7494 Propagating tree data structures dfs and similar trees Statement C Codeforces Round 225 (Div. 1) {383} PROGRAMMING Tutorial 2400
1796 On Changing Tree data structures graphs trees Statement C Codeforces Round 232 (Div. 1) {396} PROGRAMMING 1500.0 Codeforces Round #232 Editorial (restored)
241 Two Rooted Trees data structures implementation trees Statement E Codeforces Round 236 (Div. 1) {403} PROGRAMMING Editorial Codeforces Round #236 2900
747 Mashmokh and Water Tanks binary search data structures greedy trees two pointers Statement D Codeforces Round 240 (Div. 1) {414} PROGRAMMING Codeforces Round #240 Editorial 2300
545 Big Problems for Organizers data structures graphs trees Statement D RCC 2014 Warmup (Div. 1) {418} PROGRAMMING RCC 2014 WarmUp Analysis 2700
1130 Adam and Tree data structures trees Statement D Codeforces Round 253 (Div. 1) {442} PROGRAMMING Codeforces #253 editorial 2500
4143 Pillars binary search data structures dp sortings trees Statement E Codeforces Round 271 (Div. 2) {474} PROGRAMMING Codeforces Round #271 (Div. 2) Editorial 2200
7664 Interesting Array constructive algorithms data structures trees Statement B Codeforces Round 275 (Div. 1) {482} PROGRAMMING Codeforces Round #275 Editorial 2000
190 ELCA data structures trees Statement E Codeforces Round 275 (Div. 1) {482} PROGRAMMING Codeforces Round #275 Editorial 3200
2822 Tourists data structures dfs and similar graphs trees Statement E Codeforces Round 278 (Div. 1) {487} PROGRAMMING Tutorial 3100
1906 Treeland Tour data structures dfs and similar dp trees Statement F Codeforces Round 279 (Div. 2) {490} PROGRAMMING Codeforces Round #279 (Div. 2) Editorial 2500
667 Birthday data structures dfs and similar dp trees Statement D Codeforces Round 282 (Div. 1) {494} PROGRAMMING 15148 2700
6054 Misha and Forest constructive algorithms data structures greedy sortings trees Statement C Codeforces Round 285 (Div. 2) {501} PROGRAMMING Tutorial 1700
8296 A and B and Lecture Rooms binary search data structures dfs and similar dp trees Statement E Codeforces Round 294 (Div. 2) {519} PROGRAMMING 2300
485 Berland Miners binary search data structures dfs and similar greedy trees Statement A VK Cup 2015 - Round 2 (unofficial online mirror, Div. 1 only) {533} PROGRAMMING 3000
449 Tavas on the Path data structures divide and conquer trees Statement E Codeforces Round 299 (Div. 1) {536} PROGRAMMING Codeforces Round #299 Editorial 3100
2486 Infinite Inversions binary search data structures implementation sortings trees Statement E Codeforces Round 301 (Div. 2) {540} PROGRAMMING Tutorial 2400
2577 Mike and Friends data structures string suffix structures strings trees Statement E Codeforces Round 305 (Div. 1) {547} PROGRAMMING Codeforces Round #305 Editorial 2800
1211 Ann and Half-Palindrome data structures dp graphs string suffix structures strings trees Statement E Codeforces Round 311 (Div. 2) {557} PROGRAMMING Codeforces Round #311 (Div.2) Editorial 2700
806 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
4705 Duff in the Army data structures trees Statement C Codeforces Round 326 (Div. 1) {587} PROGRAMMING Codeforces Round #326 (Editorial) 2200
1421 Happy Tree Party data structures dfs and similar graphs math trees Statement D Codeforces Round 329 (Div. 2) {593} PROGRAMMING 2300
18197 Lomsat gelral data structures dfs and similar dsu trees Statement E Educational Codeforces Round 2 {600} PROGRAMMING Editorial 2300
1243 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
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
3845 Lazy Student constructive algorithms data structures graphs Statement B Codeforces Round 335 (Div. 1) {605} PROGRAMMING Codeforces Round #335 Problem Analysis 1800
641 Power Tree data structures trees Statement D Codeforces Round 336 (Div. 1) {607} PROGRAMMING Codeforces Round #336 Editorial 2600
10186 Minimum spanning tree for each edge data structures dfs and similar dsu graphs trees Statement E Educational Codeforces Round 3 {609} PROGRAMMING Editorial 2100
7037 New Year Tree bitmasks data structures trees Statement E Educational Codeforces Round 6 {620} PROGRAMMING Editorial of Educational Codeforces Round 6 2100
1148 Famil Door and Roads combinatorics data structures dfs and similar dp probabilities trees Statement E Codeforces Round 343 (Div. 2) {629} PROGRAMMING Editorial of Codeforces Round #343 (Div.2) 2400
874 Yash And Trees bitmasks data structures dfs and similar math number theory Statement G Manthan, Codefest 16 {633} PROGRAMMING Manthan, Codefest 16: Editorials 2700
450 Bear and Chemistry data structures dfs and similar graphs trees Statement F VK Cup 2016 - Round 1 {639} PROGRAMMING Tutorial 3300
1592 Zip-line binary search data structures dp hashing Statement D Codeforces Round 345 (Div. 1) {650} PROGRAMMING Codeforces Round #345: editorial 2600
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
4245 Дерево data structures trees Statement D Codeforces Round 353 (Div. 2) {675} PROGRAMMING Tutorial 1800
5314 Kay and Snowflake data structures dfs and similar dp trees Statement B Codeforces Round 359 (Div. 1) {685} PROGRAMMING Codeforces Round #359 Editorial 2000
6452 Lorenzo Von Matterhorn brute force data structures implementation trees Statement A Codeforces Round 362 (Div. 1) {696} PROGRAMMING Codeforces Round #362 (Editorial) 1500
626 ...Wait for it... data structures dsu trees Statement E Codeforces Round 362 (Div. 1) {696} PROGRAMMING Codeforces Round #362 (Editorial) 2900
347 Iron Man data structures geometry trees Statement E Codeforces Round 366 (Div. 1) {704} PROGRAMMING Tutorial 3500
12434 Vasiliy's Multiset binary search bitmasks data structures trees Statement D Codeforces Round 367 (Div. 2) {706} PROGRAMMING Tutorial 1800
4334 Centroids data structures dfs and similar dp graphs greedy trees Statement C AIM Tech Round 3 (Div. 1) {708} PROGRAMMING Editorial 2500
3344 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
1295 Drivers Dissatisfaction data structures dsu graphs trees Statement F Codeforces Round 378 (Div. 2) {733} PROGRAMMING Codeforces Round #378 (Div. 2) editorial 2500
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
3583 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
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
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
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
3453 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
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
750 ALT data structures flows graphs trees Statement E Codeforces Round 406 (Div. 1) {786} PROGRAMMING Codeforces Round #406 Editorial 3200
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
3224 Bank Hacking constructive algorithms data structures dp trees Statement C Codeforces Round 408 (Div. 2) {796} PROGRAMMING Tutorial 1900
3695 Choosing The Commander bitmasks data structures trees Statement E Educational Codeforces Round 23 {817} PROGRAMMING 52638 2100
3340 MEX Queries binary search data structures trees Statement F Educational Codeforces Round 23 {817} PROGRAMMING 52638 2400
7905 Okabe and Boxes data structures greedy trees Statement C Codeforces Round 420 (Div. 2) {821} PROGRAMMING Tutorial 1600
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
482 Red-Black Cobweb data structures divide and conquer implementation trees Statement D Codeforces Round 426 (Div. 1) {833} PROGRAMMING Codeforces Round #426 Editorial 2800
1066 Diverging Directions data structures dfs and similar trees Statement B IndiaHacks 2nd Elimination 2017 (unofficial, unrated mirror, ICPC rules) {838} PROGRAMMING 53736 2100
504 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
5456 Danil and a Part-time Job bitmasks data structures trees Statement E Codeforces Round 442 (Div. 2) {877} PROGRAMMING 55362 2000
2488 Subtree Minimum Query data structures trees Statement F Educational Codeforces Round 33 (Rated for Div. 2) {893} PROGRAMMING 55989 2300
1203 Ralph And His Tour in Binary Country brute force data structures trees Statement D Codeforces Round 447 (Div. 2) {894} PROGRAMMING Codeforces Round #447 (Div.2 Only) Editorial 2300
1904 Palindromes in a Tree bitmasks data structures divide and conquer trees Statement E Codecraft-18 and Codeforces Round 458 (Div. 1 + Div. 2, combined) {914} PROGRAMMING Tutorial 2400
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
562 Jamie and To-do List data structures interactive trees Statement D Codeforces Round 457 (Div. 2) {916} PROGRAMMING Codeforces Round #457 (Div. 2) Editorial 2600
2086 Jamie and Tree data structures trees Statement E Codeforces Round 457 (Div. 2) {916} PROGRAMMING Codeforces Round #457 (Div. 2) Editorial 2600
185 Upside Down data structures string suffix structures strings trees Statement E Codeforces Round 459 (Div. 1) {917} PROGRAMMING Codeforces Round #459 Editorial 3000
4709 Perfect Security data structures greedy strings trees Statement C VK Cup 2018 - Round 1 {923} PROGRAMMING VK Cup 2018 Round 1 and CF Round #470 (div. 1 & 2) editorial 1900
540 May Holidays data structures trees Statement E VK Cup 2018 - Round 3 {925} PROGRAMMING Разбор VK 2018 Round 3 + Codeforces Round #477 2900
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
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
347 Santa's Gift data structures trees Statement H 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 3000
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
1872 Short Code data structures dp greedy strings trees Statement E Codeforces Round 476 (Div. 2) [Thanks, Telegram!] {965} PROGRAMMING Analysis of Codeforces Round #476 (Div. 2) [Thanks, Telegram!] 2500
2171 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
2113 The Number Games data structures greedy trees Statement E Codeforces Round 480 (Div. 2) {980} PROGRAMMING Tutorial 2300
2510 Shark brute force data structures dsu trees Statement D Codeforces Round 484 (Div. 2) {982} PROGRAMMING Editorial 1900
1188 NN country binary search data structures trees Statement E Codeforces Round 483 (Div. 1) [Thanks, Botan Investments and Victor Shaburov!] {983} PROGRAMMING Codeforces Round #483 [Thanks, Botan Investments and Victor Shaburov!] Editoral 2700
893 Prince's Problem brute force data structures math number theory trees Statement E Codeforces Round 485 (Div. 1) {986} PROGRAMMING Codeforces Round #485 Editorial 2900
711 Two-Paths data structures dp trees Statement G Educational Codeforces Round 46 (Rated for Div. 2) {1000} PROGRAMMING 60288 2800
1232 Sonya and Ice Cream binary search data structures dp greedy shortest paths trees Statement E Codeforces Round 495 (Div. 2) {1004} PROGRAMMING 60443 2400
321 Ants 2-sat data structures trees Statement D Codeforces Round 497 (Div. 1) {1007} PROGRAMMING Editorial for Codeforces Round #497 by Skyglow 3200
7683 Dominant Indices data structures dsu trees Statement F Educational Codeforces Round 47 (Rated for Div. 2) {1009} PROGRAMMING 60630 2300
406 Raining season data structures divide and conquer trees Statement E Codeforces Round 503 (by SIS, Div. 1) {1019} PROGRAMMING 61161 3200
188 Pisces data structures flows trees Statement G Codeforces Round 504 (rated, Div. 1 + Div. 2, based on VK Cup 2018 Final) {1023} PROGRAMMING Codeforces Round 504 Editorial 3300
2296 You Are Given a Tree data structures dp trees Statement D Codeforces Round 507 (Div. 1, based on Olympiad of Metropolises) {1039} PROGRAMMING 61668 2700
1466 Leaf Sets data structures dfs and similar dsu graphs greedy sortings trees Statement F Codeforces Round 510 (Div. 2) {1042} PROGRAMMING Tutorial 2400
574 Last chance data structures flows graph matchings trees Statement A Bubble Cup 11 - Finals [Online Mirror, Div. 1] {1045} PROGRAMMING E 2800
210 Moonwalk challenge data structures strings trees Statement J Bubble Cup 11 - Finals [Online Mirror, Div. 1] {1045} PROGRAMMING E 3000
1619 Split the Tree binary search data structures dp greedy trees Statement E Codeforces Round 514 (Div. 2) {1059} PROGRAMMING Codeforces Round #514 (Div. 2) Editorial 2400
2049 Company binary search data structures dfs and similar greedy trees Statement E Codeforces Round 520 (Div. 2) {1062} PROGRAMMING Tutorial 2300
4138 Vasya and a Tree data structures trees Statement E Educational Codeforces Round 54 (Rated for Div. 2) {1076} PROGRAMMING E 1900
6239 The Fair Nut and the Best Path data structures dp trees Statement A Codeforces Round 526 (Div. 1) {1083} PROGRAMMING 63753 1800
1110 Max Mex data structures trees Statement C Codeforces Round 526 (Div. 1) {1083} PROGRAMMING 63753 2800
592 Ehab and a weird weight formula data structures trees Statement F Codeforces Round 525 (Div. 2) {1088} PROGRAMMING Codeforces round #525 editorial 3000
1033 Cookies binary search data structures dfs and similar dp games trees Statement F Codeforces Round 530 (Div. 2) {1099} PROGRAMMING E 2300
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
364 Sasha and Algorithm of Silence's Sounds data structures trees Statement F Codeforces Round 539 (Div. 1) {1109} PROGRAMMING Codeforces Round #539 Editorial 3200
2038 Nearest Leaf data structures trees Statement F Codeforces Global Round 1 {1110} PROGRAMMING The Editorial of the First Codeforces Global Round 2600
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
875 Niyaz and Small Degrees data structures dp trees Statement F Codeforces Global Round 2 {1119} PROGRAMMING Codeforces Global Round 2 Editorial 2900
1226 Greedy Subsequences data structures dp trees Statement G Educational Codeforces Round 61 (Rated for Div. 2) {1132} PROGRAMMING T 2600
523 Matches Are Not a Child's Play data structures trees Statement F Codeforces Round 545 (Div. 1) {1137} PROGRAMMING Codeforces Round #545 – Editorial 3300
610 Double Tree data structures divide and conquer shortest paths trees Statement G Educational Codeforces Round 62 (Rated for Div. 2) {1140} PROGRAMMING Educational Codeforces Round 62 Editorial 2900
3718 Lynyrd Skynyrd data structures dfs and similar dp math trees Statement B Codeforces Round 549 (Div. 1) {1142} PROGRAMMING Codeforces Round #549 Editorial 2300
1667 Tree Generator™ data structures implementation trees Statement C Codeforces Round 556 (Div. 1) {1149} PROGRAMMING 66783 2900
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
2444 Serge and Dining Room binary search data structures graph matchings greedy implementation math trees Statement C Codeforces Round 569 (Div. 1) {1179} PROGRAMMING Editorial of Round #569 2400
1035 Fedor Runs for President data structures dp trees Statement D Codeforces Round 569 (Div. 1) {1179} PROGRAMMING Editorial of Round #569 2600
2791 Irrigation binary search data structures implementation sortings trees two pointers Statement D Codeforces Round 567 (Div. 2) {1181} PROGRAMMING Editorial of Codeforces Round #567 (based on All-Russian olympiad in the name of Keldysh) 2100
664 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
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
507 Magic Tree *special data structures dp trees Statement B CEOI 2019 day 2 online mirror (unrated, IOI format) {1193} PROGRAMMING T
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
188 Red Blue Tree data structures implementation trees Statement H Manthan, Codefest 19 (open for everyone, rated, Div. 1 + Div. 2) {1208} PROGRAMMING 69357 3500
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
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
410 Find String in a Grid data structures dp strings trees Statement D 2019-2020 ICPC, Asia Jakarta Regional Contest (Online Mirror, ICPC Rules, Teams Preferred) {1252} PROGRAMMING T 2900
1524 Tree Queries data structures probabilities trees Statement D Codeforces Round 601 (Div. 1) {1254} PROGRAMMING Codeforces Round #601 Editorial 2600
631 Colored Tree data structures trees Statement F Educational Codeforces Round 77 (Rated for Div. 2) {1260} PROGRAMMING Educational Codeforces Round 77 Editorial 2700
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
4320 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
412 New Year and Social Network data structures graph matchings graphs math trees Statement F Hello 2020 {1284} PROGRAMMING Hello 2020 Editorial 3100
2000 Delete a Segment brute force constructive algorithms data structures dp graphs sortings trees two pointers Statement E Codeforces Round 613 (Div. 2) {1285} PROGRAMMING Codeforces Round #613 (Div. 2) Editorial 2300
5454 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
1005 Sum of Prefix Sums data structures divide and conquer geometry trees Statement G Educational Codeforces Round 82 (Rated for Div. 2) {1303} PROGRAMMING Educational Codeforces Round 82 2700
5864 1-Trees and Queries data structures dfs and similar shortest paths trees Statement E Codeforces Round 620 (Div. 2) {1304} PROGRAMMING 2000.0 Codeforces Round #620 (Div. 2) Editorial 2000
278 Journey data structures divide and conquer graphs trees Statement F Codeforces Round 635 (Div. 1) {1336} PROGRAMMING 3250.0 Codeforces Round #635 Editorial 3600
520 Train Tracks data structures trees Statement E Codeforces Round 639 (Div. 1) {1344} PROGRAMMING 2500.0 Codeforces Round #639 Editorial 3100
4951 Ehab's Last Corollary constructive algorithms data structures dfs and similar dp graphs implementation trees Statement D Codeforces Round 649 (Div. 2) {1364} PROGRAMMING 2000.0 Codeforces round #649 editorial 2100
675 Shifting Dominoes data structures geometry graphs trees Statement G Codeforces Global Round 8 {1368} PROGRAMMING 3500.0 Codeforces Global Round 8: editorial
2406 Merging Towers data structures dsu implementation trees Statement E Educational Codeforces Round 91 (Rated for Div. 2) {1380} PROGRAMMING Educational Codeforces Round 91 Editorial
2813 Removing Leaves data structures dfs and similar divide and conquer greedy implementation trees Statement F Codeforces Round 656 (Div. 3) {1385} PROGRAMMING Codeforces Round #656 (Div. 3) Editorial 2300
6902 Captain Flint and Treasure data structures dfs and similar dp graphs greedy implementation trees Statement D Codeforces Round 660 (Div. 2) {1388} PROGRAMMING 2000.0 Codeforces Round #660 Editorial 2000
2515 Weights Division (hard version) binary search data structures dfs and similar greedy trees two pointers Statement E2 Codeforces Round 661 (Div. 3) {1399} PROGRAMMING Codeforces Round #661 (Div. 3) Editorial
6329 Weights Division (easy version) data structures dfs and similar greedy trees Statement E1 Codeforces Round 661 (Div. 3) {1399} PROGRAMMING Codeforces Round #661 (Div. 3) Editorial
393 Spring cleaning *special data structures dfs and similar graphs trees Statement B Central-European Olympiad in Informatics, CEOI 2020, Day 2 (IOI, Unofficial Mirror Contest, Unrated) {1403} PROGRAMMING CEOI 2020 Online Mirror — Day 2 Tutorial
5029 XOR Inverse bitmasks data structures divide and conquer greedy strings trees Statement C Codeforces Round 673 (Div. 1) {1416} PROGRAMMING 1250.0 Codeforces Round #673 Editorial 2000
2693 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
1262 Boring Queries data structures number theory trees Statement F Codeforces Round 675 (Div. 2) {1422} PROGRAMMING 2750.0 Codeforces Round #675 (Div. 2) Editorial
398 Boring Card Game data structures greedy trees Statement F Codeforces Global Round 11 {1427} PROGRAMMING 2250.0 Editorial of Global Round 11 3200
1247 Death DBMS data structures hashing string suffix structures strings trees Statement G Educational Codeforces Round 97 (Rated for Div. 2) {1437} PROGRAMMING 84149
247 Cheat and Win bitmasks data structures games trees Statement E Codeforces Round 684 (Div. 1) {1439} PROGRAMMING 2500.0 Codeforces Round #684[Div1 and Div2] Editorial
4077 Xor Tree binary search bitmasks data structures divide and conquer dp trees Statement C Codeforces Round 683 (Div. 1, by Meet IT) {1446} PROGRAMMING 1250.0 E
6596 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
441 My Beautiful Madness data structures trees Statement F Codeforces Round 692 (Div. 1, based on Technocup 2021 Elimination Round 3) {1464} PROGRAMMING 3000.0 Technocup 2021 Elimination Round 3 and Round #692 (Div. 1 + Div. 2) Editorial
1756 Distinctive Roots in a Tree data structures dfs and similar trees Statement E Codeforces Round 695 (Div. 2) {1467} PROGRAMMING 2500.0 Codeforces Round #695 (Div. 2) Editorial 2500
1321 Odd Mineral Resource bitmasks data structures hashing probabilities trees Statement D Codeforces Round 700 (Div. 1) {1479} PROGRAMMING 2250.0 Editorial of Codeforces Round #700
810 Pairs of Paths combinatorics data structures trees Statement F Codeforces Round 703 (Div. 2) {1486} PROGRAMMING 3000.0 Codeforces Round #703 (Div. 2) Editorial
420 Squares constructive algorithms data structures graphs trees Statement F Codeforces Round 706 (Div. 1) {1495} PROGRAMMING 3250.0 Codeforces Round #706 Editorial
1053 Christmas Game data structures dfs and similar dp games math trees Statement F CodeCraft-21 and Codeforces Round 711 (Div. 2) {1498} PROGRAMMING 3000.0 CodeCraft-21 and Codeforces Round #711 (Div. 2) Editorial
32589 Yet Another Card Deck brute force data structures implementation trees Statement C Educational Codeforces Round 107 (Rated for Div. 2) {1511} PROGRAMMING 89634
2289 Nastia Plays with a Tree constructive algorithms data structures dfs and similar dp flows graphs greedy implementation trees Statement D Codeforces Round 720 (Div. 2) {1521} PROGRAMMING 2250.0 90477
9160 Compression and Expansion brute force data structures greedy implementation trees Statement C Deltix Round, Spring 2021 (open for everyone, rated, Div. 1 + Div. 2) {1523} PROGRAMMING 1500.0 Deltix Round, Spring 2021. Editorial 1600
2283 MEX Tree combinatorics constructive algorithms data structures dfs and similar math trees Statement D Codeforces Round 721 (Div. 2) {1527} PROGRAMMING 2250.0 Tutorial 2400
2940 Trees of Tranquillity data structures dfs and similar greedy trees Statement C Codeforces Round 722 (Div. 1) {1528} PROGRAMMING 1750.0 Codeforces Round #722 Editorial
3059 Gold Transfer binary search data structures greedy interactive trees Statement E Educational Codeforces Round 110 (Rated for Div. 2) {1535} PROGRAMMING 91481
8487 Playoff Tournament data structures implementation trees Statement D Educational Codeforces Round 110 (Rated for Div. 2) {1535} PROGRAMMING 91481
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
1043 Good Graph data structures dsu graphs trees Statement F Educational Codeforces Round 112 (Rated for Div. 2) {1555} PROGRAMMING 93389 2700
1017 Illusions of the Desert data structures trees Statement I COMPFEST 13 - Finals Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1575} PROGRAMMING COMPFEST 13 — Editorial
1204 Frequency Queries data structures dfs and similar trees Statement E Technocup 2022 - Elimination Round 3 {1585} PROGRAMMING 2500.0 Codeforces Round #759 (Div. 2, based on Technocup 2022 Elimination Round 3) Editorial
594 Phys Ed Online data structures dp greedy trees Statement E Codeforces Round 751 (Div. 1) {1601} PROGRAMMING 2250.0 95865 2900
661 Tree Queries binary search data structures dp dsu geometry trees Statement F Educational Codeforces Round 116 (Rated for Div. 2) {1606} PROGRAMMING 96454
243 Alphabetic Tree binary search data structures dfs and similar hashing string suffix structures strings trees Statement G Codeforces Round 758 (Div.1 + Div. 2) {1608} PROGRAMMING 2750.0 Editorial of Codeforces Round #758 (Div.1 + Div. 2)
626 Squid Game data structures dfs and similar divide and conquer greedy trees Statement H Codeforces Global Round 17 {1610} PROGRAMMING 3500.0 Codeforces Global Round 17 Editorial
9622 Replace the Numbers data structures dsu greedy trees Statement E Educational Codeforces Round 119 (Rated for Div. 2) {1620} PROGRAMMING 98061
1254 Middle Duplication data structures dfs and similar greedy strings trees Statement E Codeforces Round 763 (Div. 2) {1623} PROGRAMMING 2750.0 Codeforces Round #763 (Div. 2) Editorial
2315 Binary Spiders bitmasks data structures implementation sortings trees Statement D Codeforces Round 765 (Div. 2) {1625} PROGRAMMING 2000.0 Editorial of Codeforces Round #765 (Div. 2)
1148 Cats on the Upgrade (easy version) data structures dfs and similar divide and conquer dp graphs trees Statement E1 Codeforces Round 765 (Div. 2) {1625} PROGRAMMING 2000.0 Editorial of Codeforces Round #765 (Div. 2)
659 Cats on the Upgrade (hard version) data structures dfs and similar graphs trees Statement E2 Codeforces Round 765 (Div. 2) {1625} PROGRAMMING 1250.0 Editorial of Codeforces Round #765 (Div. 2)
1210 Groceries in Meteor Town data structures trees Statement E Codeforces Round 767 (Div. 1) {1628} PROGRAMMING 2250.0 99276
366 Perfect Matching data structures interactive trees Statement F Educational Codeforces Round 122 (Rated for Div. 2) {1633} PROGRAMMING 99539
504 Air Reform data structures dfs and similar divide and conquer dsu graphs implementation trees Statement E Codeforces Round 775 (Div. 1, based on Moscow Open Olympiad in Informatics) {1648} PROGRAMMING 2500.0 Codeforces Round #775 Editorial
454 Snowy Mountain data structures graphs greedy shortest paths trees Statement G Codeforces Round 778 (Div. 1 + Div. 2, based on Technocup 2022 Final Round) {1654} PROGRAMMING 3500.0 Editorial of Codeforces Round #778 (Div. 1 + Div. 2, based on Technocup 2022 Final Round) 2900
1119 Narrow Components data structures dfs and similar dsu trees Statement E Educational Codeforces Round 126 (Rated for Div. 2) {1661} PROGRAMMING Educational Codeforces Round 126 Editorial
2290 Unique Occurrences data structures dfs and similar divide and conquer dp dsu trees Statement F Educational Codeforces Round 129 (Rated for Div. 2) {1681} PROGRAMMING 103163 2300
6004 Permutation Graph binary search constructive algorithms data structures greedy shortest paths trees Statement D Codeforces Global Round 21 {1696} PROGRAMMING 2000.0 Editorial of Codeforces Global Round 21
5737 Passable Paths (hard version) bitmasks data structures dfs and similar dp sortings trees Statement G2 Codeforces Round 805 (Div. 3) {1702} PROGRAMMING 104763
6316 Passable Paths (easy version) data structures dfs and similar sortings trees Statement G1 Codeforces Round 805 (Div. 3) {1702} PROGRAMMING 104763
3687 Qpwoeirut and Vertices binary search data structures dsu trees Statement E Codeforces Round 809 (Div. 2) {1706} PROGRAMMING 2250.0 Codeforces Round #809 Editorial
1893 DFS Trees data structures dfs and similar dsu graphs greedy trees Statement C Codeforces Round 808 (Div. 1) {1707} PROGRAMMING 1250.0 104930
3928 XOR Tree data structures dfs and similar dsu greedy trees Statement E Educational Codeforces Round 132 (Rated for Div. 2) {1709} PROGRAMMING 105164
443 Triameter data structures dfs and similar trees Statement F Codeforces Round 813 (Div. 2) {1712} PROGRAMMING 3500.0 Codeforces Round #813 (Div. 2) Editorial
9674 Path Prefixes binary search data structures dfs and similar implementation trees Statement G Codeforces Round 811 (Div. 3) {1714} PROGRAMMING Codeforces Round #811 (Div. 3) Editorial
2181 Xor-Subsequence (hard version) bitmasks data structures dp strings trees Statement D2 Codeforces Round 815 (Div. 2) {1720} PROGRAMMING 1000.0 Codeforces Round #815 (Div. 2) Editorial
2545 Prefix Function Queries bitmasks brute force data structures hashing string suffix structures strings trees Statement E Educational Codeforces Round 134 (Rated for Div. 2) {1721} PROGRAMMING 106416
595 Electrical Efficiency combinatorics data structures dp number theory trees Statement E COMPFEST 14 - Preliminary Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1725} PROGRAMMING Tutorial
6216 Reset K Edges binary search data structures dfs and similar graphs greedy trees Statement D Educational Codeforces Round 136 (Rated for Div. 2) {1739} PROGRAMMING Educational Codeforces Round 136 Editorial
5029 Hanging Hearts constructive algorithms data structures dfs and similar dp greedy trees Statement E Codeforces Round 831 (Div. 1 + Div. 2) {1740} PROGRAMMING 2000.0 Tutorial 1800
312 MEX Tree Manipulation data structures trees Statement H Codeforces Round 831 (Div. 1 + Div. 2) {1740} PROGRAMMING 3000.0 Tutorial 3300
2645 Yet Another Array Counting Problem data structures divide and conquer dp trees Statement E Codeforces Round 833 (Div. 2) {1748} PROGRAMMING 2250.0 Codeforces Round #833 (Div. 2) Editorial 2300
610 Distance to the Path data structures dfs and similar trees Statement F Educational Codeforces Round 138 (Rated for Div. 2) {1749} PROGRAMMING 108269
10240 SlavicG's Favorite Problem bitmasks brute force constructive algorithms data structures dfs and similar graphs greedy Statement G Codeforces Round 835 (Div. 4) {1760} PROGRAMMING 109348
427 Two Subtrees data structures trees Statement F Educational Codeforces Round 140 (Rated for Div. 2) {1767} PROGRAMMING 110225
1519 Hossam and Range Minimum Query binary search bitmasks data structures hashing probabilities strings trees Statement F Codeforces Round 837 (Div. 2) {1771} PROGRAMMING 3500.0 Codeforces Round #837 (Div. 2) Editorial
603 Segment Covering brute force combinatorics constructive algorithms data structures trees Statement G Polynomial Round 2022 (Div. 1 + Div. 2, Rated, Prizes!) {1774} PROGRAMMING 3250.0 Polynomial Round 2022 (Div. 1 + Div. 2) Editorial
1334 Comfortably Numb binary search bitmasks data structures divide and conquer dsu strings trees two pointers Statement F Codeforces Round 845 (Div. 2) and ByteRace 2023 {1777} PROGRAMMING 2750.0 Codeforces Round #845 (Div. 2) and ByteRace 2023 Editorial
587 Weighed Tree Radius data structures divide and conquer trees Statement G Educational Codeforces Round 141 (Rated for Div. 2) {1783} PROGRAMMING Educational Codeforces Round 141 Editorial
1525 Labeling the Tree with Distances data structures dp hashing implementation trees Statement E Codeforces Round 856 (Div. 2) {1794} PROGRAMMING 2750.0 Codeforces Round 856 (Div. 2) Editorial
1028 Colored Subgraphs data structures dp greedy trees Statement E Educational Codeforces Round 144 (Rated for Div. 2) {1796} PROGRAMMING Educational Codeforces Round 144 Editorial
4627 Li Hua and Tree brute force data structures dfs and similar dp implementation trees Statement D Codeforces Round 864 (Div. 2) {1797} PROGRAMMING 1750.0 Codeforces Round 864 (Div. 2) Editorial
560 Li Hua and Path data structures dfs and similar divide and conquer dsu trees Statement F Codeforces Round 864 (Div. 2) {1797} PROGRAMMING 3000.0 Codeforces Round 864 (Div. 2) Editorial
614 Gasoline prices data structures divide and conquer dsu trees Statement E Codeforces Round 857 (Div. 1) {1801} PROGRAMMING 2500.0 Codeforces Round #857 Editorial
1902 There Should Be a Lot of Maximums data structures dfs and similar dsu graphs trees Statement E Codeforces Round 862 (Div. 2) {1805} PROGRAMMING 2250.0 Editorial of Codeforces Round #862 (Div. 2)
3427 Tree Master brute force data structures dfs and similar hashing trees Statement E Codeforces Round 858 (Div. 2) {1806} PROGRAMMING 2250.0 Codeforces Round #858 (Div. 2) Editorial
3896 Monsters brute force data structures dfs and similar dsu graphs implementation trees Statement E CodeTON Round 4 (Div. 1 + Div. 2, Rated, Prizes!) {1810} PROGRAMMING 2000.0 Editorial of CodeTON Round 4 (Div. 1 + Div. 2, Rated, Prizes!)
1679 LuoTianyi and XOR-Tree data structures dfs and similar dp dsu greedy trees Statement C Codeforces Round 872 (Div. 1) {1824} PROGRAMMING 1750.0 CodeForces Round 872(Div. 1&2) Editorial 2500
188 LuoTianyi and Cartridge data structures trees Statement E Codeforces Round 872 (Div. 1) {1824} PROGRAMMING 3000.0 CodeForces Round 872(Div. 1&2) Editorial 3500
965 Two Centroids data structures dfs and similar greedy trees Statement D Codeforces Round 873 (Div. 1) {1827} PROGRAMMING 1750.0 Codeforces Round #873 (Div. 1 & 2) Editorial 2800
2105 Omsk Metro (hard version) data structures dfs and similar divide and conquer dp implementation math trees Statement F2 Codeforces Round 881 (Div. 3) {1843} PROGRAMMING Codeforces Round #881 (Div. 3) Editorial
6329 Omsk Metro (simple version) data structures dfs and similar dp greedy math trees Statement F1 Codeforces Round 881 (Div. 3) {1843} PROGRAMMING Codeforces Round #881 (Div. 3) Editorial
1174 Tree Weights bitmasks constructive algorithms data structures dfs and similar math matrices number theory trees Statement G Codeforces Round 884 (Div. 1 + Div. 2) {1844} PROGRAMMING 3500.0 Codeforces Round #884 (Div. 1 + Div. 2) Editorial
877 XOR Partition binary search bitmasks data structures divide and conquer greedy trees Statement F Educational Codeforces Round 152 (Rated for Div. 2) {1849} PROGRAMMING 118752
7373 Lisa and the Martians bitmasks data structures greedy math sortings strings trees Statement F Codeforces Round 888 (Div. 3) {1851} PROGRAMMING 118667
4018 Vlad and the Mountains data structures dsu graphs implementation sortings trees two pointers Statement G Codeforces Round 888 (Div. 3) {1851} PROGRAMMING 118667
3185 Trees and Segments binary search brute force constructive algorithms data structures dp greedy two pointers Statement D Codeforces Round 893 (Div. 2) {1858} PROGRAMMING 2000.0 Codeforces Round #893 (Div. 2) Editorial 2200
1537 Rollbacks (Easy Version) brute force data structures dfs and similar trees Statement E1 Codeforces Round 893 (Div. 2) {1858} PROGRAMMING 1750.0 Codeforces Round #893 (Div. 2) Editorial 2500