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4491 How many trees? combinatorics divide and conquer dp Statement D Codeforces Beta Round 9 (Div. 2 Only) {9} PROGRAMMING Codeforces Beta Round #9 tutorial 2000
673 Triangles combinatorics dp Statement E Codeforces Beta Round 15 {15} PROGRAMMING Codeforces Beta #15 Tutorial (Incomplete) 2600
1271 Bath Queue combinatorics dp probabilities Statement C Codeforces Beta Round 28 (Codeforces format) {28} PROGRAMMING Codeforces Beta Round #28 (Разбор задач A и B) 2700
513 Lesson Timetable combinatorics dp math Statement D Codeforces Beta Round 37 {37} PROGRAMMING Codeforces Beta Round #37 (Tutorial) 2300
4243 Basketball Team combinatorics dp math probabilities Statement B Codeforces Beta Round 83 (Div. 1 Only) {107} PROGRAMMING Tutorial 1700
900 Petya and Coloring combinatorics dp Statement D Codeforces Beta Round 85 (Div. 1 Only) {111} PROGRAMMING Codeforces Beta Round #85: Разбор задач 2300
720 Brackets combinatorics dp greedy Statement C Codeforces Beta Round 92 (Div. 1 Only) {123} PROGRAMMING Codeforces Beta Round #92 - Analysis 2300
3238 Games with Rectangle combinatorics dp Statement C Codeforces Beta Round 94 (Div. 1 Only) {128} PROGRAMMING 3219 2100
1035 New Year Garland combinatorics dp Statement E Codeforces Round 100 {140} PROGRAMMING Codeforces Round #100: problem analysis 2600
2144 Lucky Subsequence combinatorics dp math Statement C Codeforces Round 104 (Div. 1) {145} PROGRAMMING Codeforces Round #104 - Editorial 2200
2619 Cipher combinatorics dp Statement C Codeforces Round 110 (Div. 1) {156} PROGRAMMING Codeforces Round 110 — Разбор задач 2100
6572 Little Elephant and Interval binary search combinatorics dp Statement A Codeforces Round 129 (Div. 1) {204} PROGRAMMING Tutorial 1600
483 Cowboys combinatorics dp math Statement C VK Cup 2012 Finals (unofficial online-version) {212} PROGRAMMING 2200
1977 Numbers combinatorics dp Statement B Codeforces Round 131 (Div. 1) {213} PROGRAMMING Codeforces Round #131 Tutorial 2200
671 Periodical Numbers combinatorics dp number theory Statement E Codeforces Round 132 (Div. 2) {215} PROGRAMMING Codeforces Round #132 (Div. 2) Tutorial 2600
524 Gifts combinatorics dp math probabilities Statement E Codeforces Round 142 (Div. 1) {229} PROGRAMMING Codeforces Round #142 Problem Analysis 2500
1651 Table bitmasks combinatorics dp math Statement B Codeforces Round 144 (Div. 1) {232} PROGRAMMING Editorial for Codeforces Round #144 2200
884 Number Challenge combinatorics dp implementation math number theory Statement E Codeforces Round 146 (Div. 1) {235} PROGRAMMING Codeforces Round #146 Tutorial 2600
1599 Little Elephant and Elections brute force combinatorics dp Statement B Codeforces Round 157 (Div. 1) {258} PROGRAMMING Codeforces Round #157 — Editorial 2100
1951 Little Elephant and LCM binary search combinatorics dp math Statement C Codeforces Round 157 (Div. 1) {258} PROGRAMMING Codeforces Round #157 — Editorial 2400
1671 Permutation Sum bitmasks combinatorics dp implementation meet-in-the-middle Statement D Codeforces Round 175 (Div. 2) {285} PROGRAMMING Codeforces Round #175 (Div. 2) Tutorial 1900
1290 Positions in Permutations combinatorics dp math Statement E Codeforces Round 175 (Div. 2) {285} PROGRAMMING Codeforces Round #175 (Div. 2) Tutorial 2600
738 Greg and Caves combinatorics dp Statement D Codeforces Round 179 (Div. 1) {295} PROGRAMMING Codeforces Round #179 tutorial 2400
1933 Greg and Friends combinatorics dp graphs shortest paths Statement C Codeforces Round 179 (Div. 1) {295} PROGRAMMING Codeforces Round #179 tutorial 2500
2667 Yaroslav and Two Strings combinatorics dp Statement B Codeforces Round 179 (Div. 2) {296} PROGRAMMING Codeforces Round #179 tutorial 2000
1575 Axis Walking bitmasks combinatorics constructive algorithms dp meet-in-the-middle Statement E Codeforces Round 191 (Div. 2) {327} PROGRAMMING Codeforces Round #191 — Tutorial 2500
126 Vasily the Bear and Painting Square bitmasks combinatorics dp implementation Statement E Codeforces Round 195 (Div. 2) {336} PROGRAMMING Tutorial Codeforces Round #195 (Div. 2) 2600
2721 Jeff and Furik combinatorics dp probabilities Statement B Codeforces Round 204 (Div. 1) {351} PROGRAMMING Codeforces Round #204 — tutorial 2100
1212 Levko and Strings combinatorics dp Statement C Codeforces Round 210 (Div. 1) {360} PROGRAMMING Codeforces Round #210 editorial 2700
1387 Sereja and Intervals combinatorics dp Statement E Codeforces Round 215 (Div. 1) {367} PROGRAMMING Codeforces Round #215 — tutorial 2600
430 Ksenia and Combinatorics combinatorics dp Statement E Codeforces Round 224 (Div. 2) {382} PROGRAMMING Codeforces Round #224 (Div. 2) Editorial 2600
4281 Vowels combinatorics divide and conquer dp Statement E Codeforces Round 225 (Div. 1) {383} PROGRAMMING Tutorial 2700
4555 Roman and Numbers bitmasks brute force combinatorics dp number theory Statement D Codeforces Round 235 (Div. 2) {401} PROGRAMMING Codeforces Round #235 (Div. 2) — Tutorial 2000
1231 Beautiful Pairs of Numbers combinatorics dp Statement D Codeforces Round 236 (Div. 1) {403} PROGRAMMING Editorial Codeforces Round #236 2200
29009 Mashmokh and ACM combinatorics dp number theory Statement B Codeforces Round 240 (Div. 1) {414} PROGRAMMING Codeforces Round #240 Editorial 1500
2871 Random Task binary search bitmasks combinatorics dp math Statement D Codeforces Round 247 (Div. 2) {431} PROGRAMMING Editorial Codeforces Round #247 (Div. 2) 2200
1835 Devu and Birthday Celebration combinatorics dp math Statement E Codeforces Round 251 (Div. 2) {439} PROGRAMMING Codeforces Round #251 Editorial 2600
6101 Jzzhu and Numbers bitmasks combinatorics dp Statement D Codeforces Round 257 (Div. 1) {449} PROGRAMMING Codeforces Round #257 Editorial 2400
3744 Increase Sequence combinatorics dp Statement D Codeforces Round 266 (Div. 2) {466} PROGRAMMING Editorial Codeforces Round #266 (Div. 2) 2300
36817 Dreamoon and WiFi bitmasks brute force combinatorics dp math probabilities Statement B Codeforces Round 272 (Div. 2) {476} PROGRAMMING 1300
5604 Riding in a Lift combinatorics dp Statement E Codeforces Round 274 (Div. 2) {479} PROGRAMMING Codeforces Round #274: editorial 2000
590 Random Function and Tree combinatorics dp trees Statement D Codeforces Round 275 (Div. 1) {482} PROGRAMMING Codeforces Round #275 Editorial 2600
1937 Special Matrices combinatorics dp Statement F Codeforces Round 277.5 (Div. 2) {489} PROGRAMMING Codeforces Round #277.5 (Div. 2) Editorial [A-D for now] 2200
916 Mr. Kitayuta's Gift combinatorics dp matrices strings Statement E Codeforces Round 286 (Div. 1) {506} PROGRAMMING Editorial 2900
8129 Ilya and Escalator combinatorics dp math probabilities Statement D Codeforces Round 293 (Div. 2) {518} PROGRAMMING Codeforces Round #293 (Div.2) Editorial 1900
417 Pasha and Pipe binary search brute force combinatorics dp implementation Statement F Codeforces Round 293 (Div. 2) {518} PROGRAMMING Codeforces Round #293 (Div.2) Editorial 2800
2083 Pluses everywhere combinatorics dp math number theory Statement E Codeforces Round 295 (Div. 2) {520} PROGRAMMING Codeforces Round #295 Editorial (now with bonuses!) 2500
25713 Tavas and SaDDas bitmasks brute force combinatorics implementation Statement B Codeforces Round 299 (Div. 2) {535} PROGRAMMING Codeforces Round #299 Editorial 1100
3383 Mike and Foam bitmasks combinatorics dp math number theory Statement C Codeforces Round 305 (Div. 1) {547} PROGRAMMING Codeforces Round #305 Editorial 2700
9790 Kyoya and Colored Balls combinatorics dp math Statement A Codeforces Round 309 (Div. 1) {553} PROGRAMMING Codeforces Round #309 Editorial 1700
8026 Gerald and Giant Chess combinatorics dp math number theory Statement C Codeforces Round 313 (Div. 1) {559} PROGRAMMING Codeforces Round 313 — Extended editoral 2500
2382 Symmetric and Transitive combinatorics dp math Statement B Codeforces Round 315 (Div. 1) {568} PROGRAMMING Codeforces Round #315 Editorial 2100
2102 Pig and Palindromes combinatorics dp Statement E Codeforces Round 316 (Div. 2) {570} PROGRAMMING Codeforces Round #316 Editorial 2600
14756 Modulo Sum combinatorics data structures dp two pointers Statement B Codeforces Round 319 (Div. 2) {577} PROGRAMMING Editorial Codeforces Round #319 1800
611 Transforming Sequence combinatorics dp fft math Statement E AIM Tech Round (Div. 1) {623} PROGRAMMING AIM Tech Round Tutorial 3300
3146 Jerry's Protest brute force combinatorics dp probabilities Statement D 8VC Venture Cup 2016 - Elimination Round {626} PROGRAMMING 23522 1800
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
1315 Fence Divercity combinatorics dp number theory Statement G Codeforces Round 346 (Div. 2) {659} PROGRAMMING Editorial for Codeforces Round #346 (Div. 2) 2500
4493 Robbers' watch brute force combinatorics dp math Statement A Codeforces Round 359 (Div. 1) {685} PROGRAMMING Codeforces Round #359 Editorial 1700
2118 Mike and Geometry Problem combinatorics data structures dp geometry implementation Statement E Codeforces Round 361 (Div. 2) {689} PROGRAMMING Tutorial 2300
2212 PLEASE combinatorics dp implementation math matrices Statement C Codeforces Round 362 (Div. 1) {696} PROGRAMMING Codeforces Round #362 (Editorial) 2200
1991 Memory and Scores combinatorics dp math Statement D Codeforces Round 370 (Div. 2) {712} PROGRAMMING Codeforces Round #370 Editorial 2100
1078 Research Rover combinatorics dp Statement E Intel Code Challenge Elimination Round (Div. 1 + Div. 2, combined) {722} PROGRAMMING Tutorial 2800
520 Uniformly Branched Trees combinatorics dp trees Statement F Intel Code Challenge Final Round (Div. 1 + Div. 2, Combined) {724} PROGRAMMING Tutorial 2800
481 Igor and Interesting Numbers brute force combinatorics dp math Statement F Codeforces Round 387 (Div. 2) {747} PROGRAMMING 49171 2600
525 New Year and Binary Tree Paths bitmasks brute force combinatorics dp Statement G Good Bye 2016 {750} PROGRAMMING Good Bye 2016 — hints and codes 3100
1022 PolandBall and Many Other Balls combinatorics divide and conquer dp fft math number theory Statement G 8VC Venture Cup 2017 - Elimination Round {755} PROGRAMMING 8VC Venture Cup 2017 — Elimination Round [Editorial] 3100
1081 Bacterial Melee brute force combinatorics dp string suffix structures Statement D 8VC Venture Cup 2017 - Final Round {756} PROGRAMMING 8VC Venture Cup 2017 — Final Round and Codeforces Round #393 Editorial 2500
205 Byteland coins combinatorics dp math Statement E 8VC Venture Cup 2017 - Final Round {756} PROGRAMMING 8VC Venture Cup 2017 — Final Round and Codeforces Round #393 Editorial 3200
1543 Bash Plays with Functions brute force combinatorics dp number theory Statement E 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 2400
218 Test Data Generation combinatorics divide and conquer dp fft math number theory Statement F VK Cup 2017 - Round 3 {773} PROGRAMMING VK Cup 2017 Round 3 + Codeforces Round #412 -- Tutorial 3400
367 Sherlock and the Encrypted Data bitmasks combinatorics dp Statement G 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 2800
3656 Anton and School - 2 combinatorics dp math number theory Statement D Codeforces Round 404 (Div. 2) {785} PROGRAMMING Editorial 2200
401 Replace All combinatorics dp math Statement G Tinkoff Challenge - Final Round (Codeforces Round 414, rated, Div. 1 + Div. 2) {794} PROGRAMMING 3400
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
905 Find a car combinatorics divide and conquer dp Statement C Codeforces Round 415 (Div. 1) {809} PROGRAMMING 52099 2900
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
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
3541 Winter is here combinatorics dp math number theory Statement D Codeforces Round 428 (Div. 2) {839} PROGRAMMING Codeforces Round #428 editorial 2200
2064 On the Bench combinatorics dp Statement C Codeforces Round 429 (Div. 1) {840} PROGRAMMING Editorial 2600
455 Shake It! combinatorics dp flows graphs Statement D Codeforces Round 431 (Div. 1) {848} PROGRAMMING Codeforces Round #431 Editorial 2900
242 Days of Floral Colours combinatorics divide and conquer dp fft math Statement E Codeforces Round 431 (Div. 1) {848} PROGRAMMING Codeforces Round #431 Editorial 3400
721 Eleventh Birthday combinatorics dp math Statement C Russian Code Cup 2017 - Finals [Unofficial Mirror, Div. 1 Only Recommended, Teams Allowed] {856} PROGRAMMING Tutorial 2400
5188 The Intriguing Obsession combinatorics dp math Statement C Codeforces Round 439 (Div. 2) {869} PROGRAMMING Tutorial 1800
735 Numbers on the blackboard combinatorics dp Statement E Codeforces Round 443 (Div. 1) {878} PROGRAMMING Editorial 3200
1210 Maximum Element combinatorics dp math Statement E Технокубок 2018 - Отборочный Раунд 3 {886} PROGRAMMING Editorial Codeforces Round 445 (and Technocup 2018 — Elimination Round 3) 2500
10454 Almost Identity Permutations combinatorics dp math Statement D Educational Codeforces Round 32 {888} PROGRAMMING Educational Codeforces Round 32 - Editorial 1600
4186 Counting Arrays combinatorics dp math number theory Statement E Educational Codeforces Round 33 (Rated for Div. 2) {893} PROGRAMMING 55989 2000
7300 Square Subsets bitmasks combinatorics dp math Statement C Codeforces Round 448 (Div. 2) {895} PROGRAMMING Codeforces Round #448(Div.2) Editorial 2000
3771 Unusual Sequences bitmasks combinatorics dp math number theory Statement D Codeforces Round 450 (Div. 2) {900} PROGRAMMING Codeforces Round #450(Div. 2). Editorial. 2100
836 New Year and Entity Enumeration bitmasks combinatorics dp math Statement E Good Bye 2017 {908} PROGRAMMING Good Bye 2017 Editorial 2400
4201 Travelling Salesman and Special Numbers brute force combinatorics dp Statement C Codecraft-18 and Codeforces Round 458 (Div. 1 + Div. 2, combined) {914} PROGRAMMING Tutorial 1800
277 Ember and Storm's Tree Game combinatorics dp games trees Statement H Codecraft-18 and Codeforces Round 458 (Div. 1 + Div. 2, combined) {914} PROGRAMMING Tutorial 2900
449 Pollywog combinatorics dp matrices Statement C Codeforces Round 459 (Div. 1) {917} PROGRAMMING Codeforces Round #459 Editorial 2800
3422 Team Work combinatorics dp math Statement E ICM Technex 2018 and Codeforces Round 463 (Div. 1 + Div. 2, combined) {932} PROGRAMMING 57796 2400
640 Fibonacci String Subsequences combinatorics dp matrices Statement F Educational Codeforces Round 39 (Rated for Div. 2) {946} PROGRAMMING 58210 2500
761 Path Counting combinatorics dp Statement H Educational Codeforces Round 40 (Rated for Div. 2) {954} PROGRAMMING 58519 2500
2264 Alternating Tree combinatorics dfs and similar divide and conquer dp probabilities trees Statement E Divide by Zero 2018 and Codeforces Round 474 (Div. 1 + Div. 2, combined) {960} PROGRAMMING Divide by Zero 2018 and Codeforces Round #474 (Div. 1 + Div. 2, combined) Editorial 2200
1201 Bandit Blues combinatorics dp fft math Statement G 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 2800
288 K Paths combinatorics data structures dp fft math Statement H Avito Code Challenge 2018 {981} PROGRAMMING Avito Code Challenge 2018 — разбор 2900
1603 Cowmpany Cowmpensation combinatorics dp math trees Statement F Codeforces Round 492 (Div. 1) [Thanks, uDebug!] {995} PROGRAMMING Editorial for Codeforces Round #492 [Thanks u-Debug!] 2700
3135 Roman Digits brute force combinatorics dp greedy math Statement B Codeforces Round 493 (Div. 1) {997} PROGRAMMING 60357 2000
5028 Yet Another Problem On a Subsequence combinatorics dp Statement D Educational Codeforces Round 46 (Rated for Div. 2) {1000} PROGRAMMING 60288 1900
2360 Inverse Coloring combinatorics dp math Statement E Educational Codeforces Round 49 (Rated for Div. 2) {1027} PROGRAMMING Educational Codeforces Round 49 Editorial 2100
992 Region Separation combinatorics dp number theory trees Statement C Codeforces Round 511 (Div. 1) {1034} PROGRAMMING Codeforces Round #511 Editorial 2900
13225 Classy Numbers combinatorics dp Statement C Educational Codeforces Round 50 (Rated for Div. 2) {1036} PROGRAMMING 61727 1800
2981 Make It One bitmasks combinatorics dp math number theory shortest paths Statement F Codeforces Round 519 by Botan Investments {1043} PROGRAMMING Codeforces Round #519 Editorial 2500
787 Shrinking Tree combinatorics dp Statement F Codeforces Round 513 by Barcelona Bootcamp (rated, Div. 1 + Div. 2) {1060} PROGRAMMING User editorial for Codeforces Round 513 by Barcelona Bootcamp (rated, Div. 1 + Div. 2) 2800
3540 Segment Sum bitmasks combinatorics dp math Statement E Educational Codeforces Round 53 (Rated for Div. 2) {1073} PROGRAMMING 62742 2300
8419 Colorful Bricks combinatorics dp math Statement C Avito Cool Challenge 2018 {1081} PROGRAMMING 63888 1600
11559 The Fair Nut and String combinatorics dp implementation Statement C Codeforces Round 526 (Div. 2) {1084} PROGRAMMING 63753 1500
708 Beautiful Matrix combinatorics data structures dp Statement G Technocup 2019 - Elimination Round 4 {1085} PROGRAMMING Technocup 2019 — Elimination Round 4 + Codeforces Round 528: editorial 2600
7465 New Year and the Permutation Concatenation combinatorics dp math Statement D Good Bye 2018 {1091} PROGRAMMING Editorial 1700
1277 The Top Scorer combinatorics dp math probabilities Statement E Educational Codeforces Round 57 (Rated for Div. 2) {1096} PROGRAMMING Разбор Educational Codeforces Round 57 2600
1052 Vladislav and a Great Legend combinatorics dp trees Statement G Hello 2019 {1097} PROGRAMMING 64310 2900
11335 Ayoub and Lost Array combinatorics dp math Statement C Codeforces Round 533 (Div. 2) {1105} PROGRAMMING Tutorial 1500
1499 Sasha and Interesting Fact from Graph Theory brute force combinatorics dp math trees Statement D Codeforces Round 539 (Div. 1) {1109} PROGRAMMING Codeforces Round #539 Editorial 2600
1139 Destroy the Colony combinatorics dp math Statement D CodeCraft-19 and Codeforces Round 537 (Div. 2) {1111} PROGRAMMING CodeCraft-19 and Codeforces Round #537 (Div. 2) Editorial 2500
630 Tree Cutting (Hard Version) combinatorics dfs and similar dp trees Statement F2 Codeforces Round 540 (Div. 3) {1118} PROGRAMMING 65396 2700
2112 Palindrome-less Arrays combinatorics divide and conquer dp Statement E Educational Codeforces Round 62 (Rated for Div. 2) {1140} PROGRAMMING Educational Codeforces Round 62 Editorial 2200
3762 Number of Components combinatorics data structures dp math Statement E Codeforces Round 553 (Div. 2) {1151} PROGRAMMING Codeforces Round #553 (Div. 2) Editorial 2100
1452 Sonya and Informatics combinatorics dp matrices probabilities Statement F Codeforces Round 553 (Div. 2) {1151} PROGRAMMING Codeforces Round #553 (Div. 2) Editorial 2500
929 Serval and Bonus Problem combinatorics dp math probabilities Statement F Codeforces Round 551 (Div. 2) {1153} PROGRAMMING Editorial 2800
4403 Nauuo and Circle combinatorics dfs and similar dp trees Statement B Codeforces Round 564 (Div. 1) {1172} PROGRAMMING Codeforces Round #564 Editorial 2000
1771 Ehab and the Expected GCD Problem combinatorics dp math number theory Statement E Codeforces Round 563 (Div. 2) {1174} PROGRAMMING Codeforces round #563 editorial 2500
2279 Short Colorful Strip combinatorics dfs and similar dp Statement F1 Codeforces Global Round 4 {1178} PROGRAMMING E 2200
3403 Flag brute force combinatorics dp implementation Statement C Codeforces Round 567 (Div. 2) {1181} PROGRAMMING Editorial of Codeforces Round #567 (based on All-Russian olympiad in the name of Keldysh) 1900
3194 Playlist for Polycarp (easy version) bitmasks combinatorics dp Statement G1 Codeforces Round 568 (Div. 2) {1185} PROGRAMMING Editorial for Codeforces Round #568 (Div. 2) 2100
917 Playlist for Polycarp (hard version) combinatorics dp Statement G2 Codeforces Round 568 (Div. 2) {1185} PROGRAMMING Editorial for Codeforces Round #568 (Div. 2) 2800
1207 Crossword Expert combinatorics dp number theory probabilities two pointers Statement F Educational Codeforces Round 68 (Rated for Div. 2) {1194} PROGRAMMING Разбор Educational Codeforces Round 68 2500
1848 Culture Code binary search combinatorics data structures dp shortest paths sortings Statement E Educational Codeforces Round 69 (Rated for Div. 2) {1197} PROGRAMMING E 2300
2046 Natasha, Sasha and the Prefix Sums combinatorics dp math number theory Statement E Codeforces Round 581 (Div. 2) {1204} PROGRAMMING 69244 2400
18219 The Number of Products combinatorics dp implementation Statement B Codeforces Round 585 (Div. 2) {1215} PROGRAMMING Codeforces Round #585 Editorial 1500
875 Graph And Numbers bitmasks brute force combinatorics dp meet-in-the-middle Statement G Educational Codeforces Round 73 (Rated for Div. 2) {1221} PROGRAMMING Разбор Educational Codeforces Round 73 2900
3444 Another Filling the Grid combinatorics dp math Statement E Codeforces Round 589 (Div. 2) {1228} PROGRAMMING 70162 2300
1090 Balanced Domino Placements combinatorics dp Statement F Codeforces Global Round 5 {1237} PROGRAMMING T 2600
6438 AB-string binary search combinatorics dp strings Statement D Educational Codeforces Round 74 (Rated for Div. 2) {1238} PROGRAMMING Educational Codeforces Round 74 Editorial 1800
7790 Ivan the Fool and the Probability Theory combinatorics dp math Statement A Codeforces Round 594 (Div. 1) {1239} PROGRAMMING Editorial of Codeforces Round #594 (on the problems of Moscow Team Olympiad) 1700
2260 Daniel and Spring Cleaning bitmasks brute force combinatorics dp Statement F Codeforces Round 597 (Div. 2) {1245} PROGRAMMING Codeforces Round #597 (Div. 2) Editorial 2300
1524 Beautiful Bracket Sequence (easy version) combinatorics dp probabilities Statement D1 Codeforces Round 604 (Div. 1) {1264} PROGRAMMING 71995 2600
3706 Common Number binary search combinatorics dp math Statement E Codeforces Round 608 (Div. 2) {1271} PROGRAMMING 72247 2100
30665 Yet Another Broken Keyboard combinatorics dp implementation Statement C Codeforces Round 605 (Div. 3) {1272} PROGRAMMING Codeforces Round #605 (Div. 3) Editorial 1100
2470 Cards combinatorics dp math number theory probabilities Statement F Educational Codeforces Round 78 (Rated for Div. 2) {1278} PROGRAMMING Educational Codeforces Round 78 Editorial 2600
455 New Year Permutations combinatorics dp Statement E Educational Codeforces Round 79 (Rated for Div. 2) {1279} PROGRAMMING Educational Codeforces Round 79 Editorial 2700
11446 New Year and Ascent Sequence binary search combinatorics data structures dp implementation sortings Statement B Hello 2020 {1284} PROGRAMMING Hello 2020 Editorial 1500
15177 Two Arrays combinatorics dp Statement C Educational Codeforces Round 80 (Rated for Div. 2) {1288} PROGRAMMING Educational Codeforces Round 80 Editorial 1600
2250 Xenon's Attack on the Gangs combinatorics dfs and similar dp greedy trees Statement C Codeforces Round 614 (Div. 1) {1292} PROGRAMMING 1250.0 Codeforces Round #614 Editorial 2300
368 Nora's Toy Boxes bitmasks combinatorics dp Statement F Codeforces Round 614 (Div. 1) {1292} PROGRAMMING 2750.0 Codeforces Round #614 Editorial 3400
1507 Good Contest combinatorics dp probabilities Statement F Educational Codeforces Round 81 (Rated for Div. 2) {1295} PROGRAMMING Educational Codeforces Round 81 Editorial 2600
528 Around the World bitmasks combinatorics dfs and similar dp graphs graphs math trees Statement D Codeforces Round 618 (Div. 1) {1299} PROGRAMMING 1750.0 Codeforces Round #618 Editorial 2900
1362 Cow and Treats binary search combinatorics dp greedy implementation math Statement E Codeforces Round 621 (Div. 1 + Div. 2) {1307} PROGRAMMING 2500.0 Codeforces Round #621 (Div. 1 + Div. 2) Editorial 2400
9585 Count The Blocks combinatorics dp math Statement E Educational Codeforces Round 84 (Rated for Div. 2) {1327} PROGRAMMING Educational Codeforces Round 84 Editorial 1800
2021 AND Segments bitmasks combinatorics data structures dp two pointers Statement F Educational Codeforces Round 84 (Rated for Div. 2) {1327} PROGRAMMING Educational Codeforces Round 84 Editorial 2500
7049 Dreamoon Likes Sequences bitmasks combinatorics dp math Statement B Codeforces Round 631 (Div. 1) - Thanks, Denis aramis Shitov! {1329} PROGRAMMING 750.0 Codeforces Round #631 Editorial 1900
4616 Two Arrays binary search brute force combinatorics dp greedy implementation two pointers Statement E Educational Codeforces Round 89 (Rated for Div. 2) {1366} PROGRAMMING Educational Codeforces Round 89 Editorial
9538 Unmerge combinatorics dp two pointers Statement B Codeforces Round 658 (Div. 1) {1381} PROGRAMMING 1500.0 Codeforces Round #658 Editorial 1800
233 Star Trek *special combinatorics dfs and similar dp games graphs matrices trees Statement C Central-European Olympiad in Informatics, CEOI 2020, Day 1 (IOI, Unofficial Mirror Contest, Unrated) {1402} PROGRAMMING Editorial
75 Chess Rush *special combinatorics dp implementation math Statement C Central-European Olympiad in Informatics, CEOI 2020, Day 2 (IOI, Unofficial Mirror Contest, Unrated) {1403} PROGRAMMING CEOI 2020 Online Mirror — Day 2 Tutorial
1292 Clusterization Counting combinatorics dp dsu fft graphs Statement G Grakn Forces 2020 {1408} PROGRAMMING 3000.0 Grakn Forces -- Editorial
897 Danger of Mad Snakes combinatorics dp math Statement D 2020 ICPC, COMPFEST 12, Indonesia Multi-Provincial Contest (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1425} PROGRAMMING Tutorial 2300
6138 Number of Subsequences combinatorics dp strings Statement F Codeforces Round 674 (Div. 3) {1426} PROGRAMMING 83120 2000
1602 Emotional Fishermen combinatorics dp math Statement F Educational Codeforces Round 97 (Rated for Div. 2) {1437} PROGRAMMING 84149
475 INOI Final Contests combinatorics dp Statement D Codeforces Round 684 (Div. 1) {1439} PROGRAMMING 2500.0 Codeforces Round #684[Div1 and Div2] Editorial
8668 Radio Towers combinatorics dp math Statement D Educational Codeforces Round 98 (Rated for Div. 2) {1452} PROGRAMMING 84847
3987 Sum of Paths combinatorics dp math Statement D Codeforces Round 695 (Div. 2) {1467} PROGRAMMING 1750.0 Codeforces Round #695 (Div. 2) Editorial 2200
375 Strange Permutation binary search combinatorics data structures dp two pointers Statement E Codeforces Round 694 (Div. 1) {1470} PROGRAMMING 2000.0 86464
454 Tiles combinatorics dp fft math Statement G Educational Codeforces Round 102 (Rated for Div. 2) {1473} PROGRAMMING Educational Codeforces Round 102 Editorial
2326 Copy or Prefix Sum combinatorics data structures dp sortings Statement F Codeforces Round 701 (Div. 2) {1485} PROGRAMMING 3000.0 Editorial of Codeforces Round #701 (Div. 2) 2400
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
699 String Counting combinatorics dp math Statement G Educational Codeforces Round 104 (Rated for Div. 2) {1487} PROGRAMMING 87873
12064 Planar Reflections brute force combinatorics data structures dp Statement C CodeCraft-21 and Codeforces Round 711 (Div. 2) {1498} PROGRAMMING 1750.0 CodeCraft-21 and Codeforces Round #711 (Div. 2) Editorial
1659 Chaotic Merge combinatorics dp Statement E Educational Codeforces Round 106 (Rated for Div. 2) {1499} PROGRAMMING Educational Codeforces Round 106 Editorial
888 2-Coloring combinatorics dp math Statement E Codeforces Round 712 (Div. 1) {1503} PROGRAMMING 2500.0 T 3100
4414 Almost Sorted binary search bitmasks combinatorics constructive algorithms dp implementation math Statement B Codeforces Round 715 (Div. 1) {1508} PROGRAMMING 1000.0 Codeforces Round #715 Editorial
2891 Colorings and Dominoes combinatorics dp math Statement E Educational Codeforces Round 107 (Rated for Div. 2) {1511} PROGRAMMING 89634
4453 Phoenix and Computers combinatorics dp math Statement E Codeforces Global Round 14 {1515} PROGRAMMING 2750.0 Editorial
1002 Baby Ehab Plays with Permutations combinatorics dp math Statement E Codeforces Round 717 (Div. 2) {1516} PROGRAMMING 2750.0 Codeforces round #717 editorial
1919 Crypto Lights combinatorics dp probabilities Statement E Deltix Round, Spring 2021 (open for everyone, rated, Div. 1 + Div. 2) {1523} PROGRAMMING 2250.0 Deltix Round, Spring 2021. Editorial 2600
2365 Assimilation IV combinatorics dp math probabilities Statement E Educational Codeforces Round 109 (Rated for Div. 2) {1525} PROGRAMMING 90793
600 Mashtali and Hagh Trees combinatorics dp trees Statement E Codeforces Round 722 (Div. 1) {1528} PROGRAMMING 2750.0 Codeforces Round #722 Editorial
13768 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
2983 Tree Array brute force combinatorics dp math probabilities trees Statement B Codeforces Round 728 (Div. 1) {1540} PROGRAMMING 1250.0 Tutorial
1433 Abnormal Permutation Pairs (easy version) combinatorics dp fft math Statement E1 Codeforces Round 729 (Div. 2) {1542} PROGRAMMING 2000.0
2915 Priority Queue combinatorics dp implementation math Statement D Codeforces Round 729 (Div. 2) {1542} PROGRAMMING 2000.0
1012 Abnormal Permutation Pairs (hard version) combinatorics dp math Statement E2 Codeforces Round 729 (Div. 2) {1542} PROGRAMMING 1000.0
2015 The Three Little Pigs combinatorics dp fft math Statement C Codeforces Round 736 (Div. 1) {1548} PROGRAMMING 1750.0 Codeforces Round 736 Editorial
2167 Equidistant Vertices combinatorics dfs and similar dp trees Statement F Codeforces Round 734 (Div. 3) {1551} PROGRAMMING Editorial for Codeforces Round #734 (Div.3)
6279 Maximize the Intersections combinatorics constructive algorithms geometry greedy Statement C Codeforces Global Round 15 {1552} PROGRAMMING 1000.0 Editorial of Global Round 15
1415 Sports Betting bitmasks combinatorics dp graphs math probabilities Statement F Deltix Round, Summer 2021 (open for everyone, rated, Div. 1 + Div. 2) {1556} PROGRAMMING 2500.0 94384 2500
10459 Moamen and XOR bitmasks combinatorics dp math Statement C Codeforces Round 737 (Div. 2) {1557} PROGRAMMING 1750.0 Codeforces Round #737 Editorial
2703 Mocha and Stars combinatorics dp fft math number theory Statement E Codeforces Round 738 (Div. 2) {1559} PROGRAMMING 3000.0 Tutorial (en) 2200
13143 Carrying Conundrum bitmasks combinatorics dp Statement C Codeforces Round 742 (Div. 2) {1567} PROGRAMMING 1500.0 Codeforces Round #742 Editorial
740 Occurrences combinatorics dp dsu fft graphs Statement F Educational Codeforces Round 114 (Rated for Div. 2) {1574} PROGRAMMING 95188
1276 Mathematics Curriculum combinatorics dp trees Statement B Codeforces Round 745 (Div. 1) {1580} PROGRAMMING 1000.0 Codeforces Round #745 Editorial 2600
1662 Non-equal Neighbours combinatorics dp math Statement F Technocup 2022 - Elimination Round 3 {1585} PROGRAMMING 3000.0 Codeforces Round #759 (Div. 2, based on Technocup 2022 Elimination Round 3) Editorial
336 Non-equal Neighbours combinatorics data structures dp math Statement F Codeforces Round 759 (Div. 2, based on Technocup 2022 Elimination Round 3) {1591} PROGRAMMING 3000.0 Codeforces Round #759 (Div. 2, based on Technocup 2022 Elimination Round 3) Editorial
2489 Staircases brute force combinatorics data structures dfs and similar dp Statement E Educational Codeforces Round 115 (Rated for Div. 2) {1598} PROGRAMMING 95890
629 A Perfect Problem combinatorics dp Statement E Codeforces Round 752 (Div. 1) {1603} PROGRAMMING 3500.0 Editorial of Codeforces Round #752
346 October 18, 2017 combinatorics dp implementation math Statement F Codeforces Round 752 (Div. 1) {1603} PROGRAMMING 3750.0 Editorial of Codeforces Round #752
429 PalindORme combinatorics dp Statement F Codeforces Round 754 (Div. 2) {1605} PROGRAMMING 3500.0 tutorial 2900
4170 Arena combinatorics dp Statement E Educational Codeforces Round 116 (Rated for Div. 2) {1606} PROGRAMMING 96454
833 MEX counting combinatorics dp Statement F Codeforces Round 758 (Div.1 + Div. 2) {1608} PROGRAMMING 2500.0 Editorial of Codeforces Round #758 (Div.1 + Div. 2)
11282 Divan and bitwise operations bitmasks combinatorics constructive algorithms dp math Statement C Codeforces Round 757 (Div. 2) {1614} PROGRAMMING 1500.0 Tutorial 1500
1147 LEGOndary Grandmaster combinatorics dp math Statement F Codeforces Global Round 18 {1615} PROGRAMMING 3000.0 Global Round 18 Editorial
1228 Keep XOR Low bitmasks combinatorics divide and conquer dp math Statement H Good Bye 2021: 2022 is NEAR {1616} PROGRAMMING 4000.0 Good Bye 2021 -- Editorial 3000
1153 Subsequences Galore bitmasks combinatorics dp math Statement G Educational Codeforces Round 119 (Rated for Div. 2) {1620} PROGRAMMING 98061
900 A Random Code Problem combinatorics dp math number theory Statement F Educational Codeforces Round 121 (Rated for Div. 2) {1626} PROGRAMMING 99136
3684 Game on Sum (Easy Version) combinatorics dp games Statement D1 Codeforces Round 767 (Div. 1) {1628} PROGRAMMING 1000.0 99276
2608 Game on Sum (Hard Version) combinatorics dp games Statement D2 Codeforces Round 767 (Div. 1) {1628} PROGRAMMING 750.0 99276
2477 Star MST combinatorics dp math Statement E Educational Codeforces Round 125 (Rated for Div. 2) {1657} PROGRAMMING 101161
1515 Fancy Stack combinatorics dp Statement F 2021-2022 ICPC, NERC, Northern Eurasia Onsite (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1666} PROGRAMMING Tutorial (PDF)
803 Centroid Probabilities combinatorics dp fft math Statement E Codeforces Round 783 (Div. 1) {1667} PROGRAMMING 2750.0 Codeforces Round #783 Editorial 3000
1257 Jee, You See? bitmasks combinatorics dp Statement F Codeforces Round 788 (Div. 2) {1670} PROGRAMMING 3000.0 Tutorial 2400
423 Permutation Counting brute force combinatorics dp fft math Statement F Educational Codeforces Round 127 (Rated for Div. 2) {1671} PROGRAMMING 102181
3162 Preorder combinatorics divide and conquer dp dsu hashing trees Statement E Educational Codeforces Round 127 (Rated for Div. 2) {1671} PROGRAMMING 102181
1412 Typical Party in Dorm bitmasks brute force combinatorics dp strings two pointers Statement E Codeforces Round 791 (Div. 2) {1679} PROGRAMMING 2250.0 Codeforces Round #791 (Div. 2) Editorial
1130 K-Set Tree combinatorics dfs and similar dp math trees Statement F CodeCraft-22 and Codeforces Round 795 (Div. 2) {1691} PROGRAMMING 2750.0 Editorial for CodeCraft-22 and Codeforces Round #795 (Div. 2)
203 Maximum Product? brute force combinatorics dp greedy math two pointers Statement H Codeforces Global Round 21 {1696} PROGRAMMING 4000.0 Editorial of Codeforces Global Round 21
1449 Coloring brute force combinatorics constructive algorithms dfs and similar dp dsu graphs implementation Statement E Educational Codeforces Round 130 (Rated for Div. 2) {1697} PROGRAMMING 103835
889 Partial Virtual Trees combinatorics dp math trees Statement D Codeforces Round 808 (Div. 1) {1707} PROGRAMMING 1750.0 104930
681 Lost Array bitmasks combinatorics constructive algorithms dp math Statement F Codeforces Round 812 (Div. 2) {1713} PROGRAMMING 3000.0 Codeforces Round #812 (Div. 2) Editorial 2900
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
613 Illumination combinatorics dp Statement G Educational Codeforces Round 135 (Rated for Div. 2) {1728} PROGRAMMING 106805
2498 Cut Substrings combinatorics dp hashing strings two pointers Statement G Codeforces Round 820 (Div. 3) {1729} PROGRAMMING Codeforces Round #820 (Div. 3) Editorial
846 Function Sum brute force combinatorics dp fft math Statement F Codeforces Round 841 (Div. 2) and Divide by Zero 2022 {1731} PROGRAMMING 2750.0 Codeforces Round #841 (Div. 2) and Divide By Zero 2022 Editorial
1792 Balance Addicts combinatorics dp math two pointers Statement E Codeforces Global Round 22 {1738} PROGRAMMING 2500.0 Editorial of Codeforces Global Round <strong>22</strong>
10070 Card Game combinatorics constructive algorithms dp games Statement C Educational Codeforces Round 136 (Rated for Div. 2) {1739} PROGRAMMING Educational Codeforces Round 136 Editorial
1065 Conditional Mix combinatorics dp math Statement F Codeforces Round 831 (Div. 1 + Div. 2) {1740} PROGRAMMING 2500.0 Tutorial 2600
1793 Intersection and Union combinatorics data structures dp math matrices Statement F Educational Codeforces Round 137 (Rated for Div. 2) {1743} PROGRAMMING Educational Codeforces Round 137 Editorial 2300
304 Antifibonacci Cut bitmasks combinatorics dp math Statement G Educational Codeforces Round 137 (Rated for Div. 2) {1743} PROGRAMMING Educational Codeforces Round 137 Editorial 3000
7334 Count GCD bitmasks combinatorics dp math number theory Statement D CodeTON Round 3 (Div. 1 + Div. 2, Rated, Prizes!) {1750} PROGRAMMING 1750.0 CodeTON Round 3 (Div. 1 + Div. 2) Editorial
2760 Carry Bit bitmasks brute force combinatorics dp math Statement D Pinely Round 1 (Div. 1 + Div. 2) {1761} PROGRAMMING 1750.0 Pinely Round 1 (Div. 1 + Div. 2) Editorial
102 Anti-median (Hard Version) combinatorics dp math Statement F2 Pinely Round 1 (Div. 1 + Div. 2) {1761} PROGRAMMING 2000.0 Pinely Round 1 (Div. 1 + Div. 2) Editorial
10147 Binary Strings are Fun combinatorics dp Statement C Codeforces Round 838 (Div. 2) {1762} PROGRAMMING 1750.0 Codeforces Round #838 (Div. 2) Editorial
846 Tree Sum combinatorics trees Statement E Codeforces Round 838 (Div. 2) {1762} PROGRAMMING 2500.0 Codeforces Round #838 (Div. 2) Editorial
2341 Valid Bitonic Permutations combinatorics dp implementation math Statement D Codeforces Round 840 (Div. 2) and Enigma 2022 - Cybros LNMIIT {1763} PROGRAMMING 2000.0 Codeforces Round #840 (Div. 2) and Enigma 2022 — Cybros LNMIIT Editorial
11188 Playoff combinatorics constructive algorithms dp graphs greedy Statement D Educational Codeforces Round 140 (Rated for Div. 2) {1767} PROGRAMMING 110225
1607 Koxia and Tree combinatorics dp math probabilities trees Statement E Good Bye 2022: 2023 is NEAR {1770} PROGRAMMING 2000.0 Good Bye 2022 -- Editorial
857 Laboratory on Pluto brute force combinatorics dp fft greedy math Statement F Codeforces Round 843 (Div. 2) {1775} PROGRAMMING 3000.0 Codeforces Round #843 (Div. 2) Editorial
4660 Score of a Tree bitmasks combinatorics dfs and similar dp probabilities trees Statement D Codeforces Round 845 (Div. 2) and ByteRace 2023 {1777} PROGRAMMING 2000.0 Codeforces Round #845 (Div. 2) and ByteRace 2023 Editorial
3388 Flexible String Revisit combinatorics dp math probabilities Statement D Codeforces Round 848 (Div. 2) {1778} PROGRAMMING 1750.0 Codeforces Round #848 (Div. 2) Editorial
1312 Bracket Insertion brute force combinatorics constructive algorithms dp math trees Statement F VK Cup 2022 - Отборочный раунд (Engine) {1781} PROGRAMMING 3250.0 Tutorial
1289 Wooden Spoon combinatorics dp Statement D VK Cup 2022 - Финальный раунд (Engine) {1784} PROGRAMMING 2000.0 Codeforces Round #850 Editorial
461 Infinite Game combinatorics dp games probabilities Statement E VK Cup 2022 - Финальный раунд (Engine) {1784} PROGRAMMING 3000.0 Codeforces Round #850 Editorial
4635 Moving Dots binary search brute force combinatorics dp math two pointers Statement D Codeforces Round 851 (Div. 2) {1788} PROGRAMMING 2250.0 Codeforces Round #851 (Div. 2) Editorial
4450 Counting Factorizations combinatorics dp math number theory Statement D Codeforces Round 856 (Div. 2) {1794} PROGRAMMING 2000.0 Codeforces Round 856 (Div. 2) Editorial
12143 Maximum Set binary search brute force combinatorics dp math Statement C Educational Codeforces Round 144 (Rated for Div. 2) {1796} PROGRAMMING Educational Codeforces Round 144 Editorial
1064 Count Voting combinatorics dp math Statement G Codeforces Round 854 by cybercats (Div. 1 + Div. 2) {1799} PROGRAMMING 3000.0 Codeforces Round #854 Editorial
1184 DSU Master combinatorics dp dsu math Statement D Codeforces Round 858 (Div. 2) {1806} PROGRAMMING 2000.0 Codeforces Round #858 (Div. 2) Editorial
1588 Minibuses on Venus (easy version) brute force combinatorics dp Statement E1 Codeforces Round 861 (Div. 2) {1808} PROGRAMMING 1750.0 Codeforces Round #861 (Div. 2) editorial 2200