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928 Tickets combinatorics math probabilities Statement D Codeforces Beta Round 26 (Codeforces format) {26} PROGRAMMING Разбор Codeforces Beta Round #26 (ещё один) 2800
513 Lesson Timetable combinatorics dp math Statement D Codeforces Beta Round 37 {37} PROGRAMMING Codeforces Beta Round #37 (Tutorial) 2300
3943 Array combinatorics math Statement C Codeforces Beta Round 53 {57} PROGRAMMING Codeforces Beta Round #53 [Analysis] 1900
135534 Ultra-Fast Mathematician implementation Statement A Codeforces Beta Round 57 (Div. 2) {61} PROGRAMMING Round 57-A 900
4243 Basketball Team combinatorics dp math probabilities Statement B Codeforces Beta Round 83 (Div. 1 Only) {107} PROGRAMMING Tutorial 1700
142 Sleeping combinatorics implementation math Statement E Codeforces Beta Round 86 (Div. 1 Only) {113} PROGRAMMING Codeforces Beta Round #86 Editorial 2600
12538 The World is a Theatre combinatorics math Statement C Codeforces Beta Round 95 (Div. 2) {131} PROGRAMMING Разбор Codeforces Beta Round #95 (Div.2) 1500
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
5292 Quantity of Strings combinatorics dfs and similar graphs math Statement B Codeforces Round 107 (Div. 1) {150} PROGRAMMING Tutorial 1800
483 Cowboys combinatorics dp math Statement C VK Cup 2012 Finals (unofficial online-version) {212} PROGRAMMING 2200
273 Bitonix' Patrol bitmasks brute force combinatorics dfs and similar math Statement D Codeforces Round 134 (Div. 1) {217} PROGRAMMING Editorial for Codeforces Round #134 2800
1750 Partial Sums combinatorics math number theory Statement C Codeforces Round 138 (Div. 1) {223} PROGRAMMING Tutorial 2200
1778 Triangles combinatorics graphs math Statement C Codeforces Round 142 (Div. 1) {229} PROGRAMMING Codeforces Round #142 Problem Analysis 2100
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
1951 Little Elephant and LCM binary search combinatorics dp math Statement C Codeforces Round 157 (Div. 1) {258} PROGRAMMING Codeforces Round #157 — Editorial 2400
2828 Dima and Two Sequences combinatorics math sortings Statement D Codeforces Round 167 (Div. 2) {272} PROGRAMMING Codeforces Round #167 tutorial 1800
853 Cow Tennis Tournament combinatorics data structures math Statement E Codeforces Round 174 (Div. 1) {283} PROGRAMMING Math Problems on Codeforces #174 2700
1290 Positions in Permutations combinatorics dp math Statement E Codeforces Round 175 (Div. 2) {285} PROGRAMMING Codeforces Round #175 (Div. 2) Tutorial 2600
555 Olya and Graph combinatorics math Statement D Codeforces Round 184 (Div. 2) {305} PROGRAMMING 7712 2600
3019 Malek Dance Club combinatorics math Statement A Codeforces Round 189 (Div. 1) {319} PROGRAMMING Codeforces Round #189 — Editorial 1700
13152 Ciel and Flowers combinatorics math Statement B Codeforces Round 190 (Div. 2) {322} PROGRAMMING Codeforces Round #190 — Editorial 1600
3659 Magic Five combinatorics math Statement C Codeforces Round 191 (Div. 2) {327} PROGRAMMING Codeforces Round #191 — Tutorial 1700
1212 Vasily the Bear and Beautiful Strings combinatorics math number theory Statement D Codeforces Round 195 (Div. 2) {336} PROGRAMMING Tutorial Codeforces Round #195 (Div. 2) 2400
4668 Tourist Problem combinatorics implementation math Statement C Codeforces Round 198 (Div. 2) {340} PROGRAMMING Tutorial 1700
2742 Iahub and Permutations combinatorics math Statement E Codeforces Round 198 (Div. 2) {340} PROGRAMMING Tutorial 2200
2721 Jeff and Furik combinatorics dp probabilities Statement B Codeforces Round 204 (Div. 1) {351} PROGRAMMING Codeforces Round #204 — tutorial 2100
2430 Two Heaps combinatorics constructive algorithms greedy implementation math sortings Statement B Codeforces Round 205 (Div. 2) {353} PROGRAMMING 9145 1800
521 Sereja and Cinema combinatorics math Statement D Codeforces Round 223 (Div. 1) {380} PROGRAMMING Codeforces Round #223 — Tutorial 2500
664 Yet Another Number Sequence combinatorics math matrices Statement C Codeforces Round 230 (Div. 1) {392} PROGRAMMING 1500.0 83942
464 On Sum of Number of Inversions in Permutations combinatorics math Statement D Codeforces Round 232 (Div. 1) {396} PROGRAMMING 2000.0 Codeforces Round #232 Editorial (restored)
1626 On Number of Decompositions into Multipliers combinatorics math number theory Statement A Codeforces Round 232 (Div. 1) {396} PROGRAMMING 500.0 Codeforces Round #232 Editorial (restored)
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
1189 Curious Array brute force combinatorics implementation math Statement C Codeforces Round 239 (Div. 1) {407} PROGRAMMING Codeforces Round #239 Editorial 2500
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
1748 Magic Trick combinatorics math probabilities Statement C MemSQL Start[c]UP 2.0 - Round 1 {452} PROGRAMMING MemSQL Start[c]UP 2.0 Round 1 and 2 Editorials 2100
388 Bingo! combinatorics math probabilities Statement D MemSQL Start[c]UP 2.0 - Round 2 {457} PROGRAMMING MemSQL Start[c]UP 2.0 Round 1 and 2 Editorials 2700
6480 Pashmak and Buses combinatorics constructive algorithms math Statement C Codeforces Round 261 (Div. 2) {459} PROGRAMMING Codeforces Round #261 Editorial 1900
36817 Dreamoon and WiFi bitmasks brute force combinatorics dp math probabilities Statement B Codeforces Round 272 (Div. 2) {476} PROGRAMMING 1300
41118 Random Teams combinatorics constructive algorithms greedy math Statement B Codeforces Round 273 (Div. 2) {478} PROGRAMMING Editorial 1300
8129 Ilya and Escalator combinatorics dp math probabilities Statement D Codeforces Round 293 (Div. 2) {518} PROGRAMMING Codeforces Round #293 (Div.2) Editorial 1900
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
3383 Mike and Foam bitmasks combinatorics dp math number theory Statement C Codeforces Round 305 (Div. 1) {547} PROGRAMMING Codeforces Round #305 Editorial 2700
2097 GukiZ and Binary Operations combinatorics implementation math matrices number theory Statement D Codeforces Round 307 (Div. 2) {551} PROGRAMMING Tutorial 2400
4839 Vanya and Triangles brute force combinatorics data structures geometry math sortings Statement D Codeforces Round 308 (Div. 2) {552} PROGRAMMING Codeforces #308 (Div. 2) Editorial 1900
9790 Kyoya and Colored Balls combinatorics dp math Statement A Codeforces Round 309 (Div. 1) {553} PROGRAMMING Codeforces Round #309 Editorial 1700
2263 Kyoya and Permutation binary search combinatorics constructive algorithms greedy implementation math Statement B Codeforces Round 309 (Div. 1) {553} PROGRAMMING Codeforces Round #309 Editorial 2200
2373 Vitaly and Cycle combinatorics dfs and similar graphs math Statement D Codeforces Round 311 (Div. 2) {557} PROGRAMMING Codeforces Round #311 (Div.2) Editorial 2300
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
2676 Lengthening Sticks combinatorics implementation math Statement A Codeforces Round 317 [AimFund Thanks-Round] (Div. 1) {571} PROGRAMMING Codeforces Round #317 [AimFund Thanks-Round] Editorial 2300
1220 Present for Vitalik the Philatelist combinatorics math number theory Statement E Codeforces Round 325 (Div. 1) {585} PROGRAMMING Разбор Codeforces Round #325 2800
2708 Moodular Arithmetic combinatorics dfs and similar dsu math number theory Statement B Codeforces Round 334 (Div. 1) {603} PROGRAMMING Codeforces Round #334 Editorial 2000
27497 Pasha and Stick combinatorics math Statement A Codeforces Round 337 (Div. 2) {610} PROGRAMMING Codeforces Round #337 (Div.2) Editorial 1000
1998 Square Root of Permutation combinatorics constructive algorithms dfs and similar graphs math Statement E Educational Codeforces Round 4 {612} PROGRAMMING 22299 2200
6218 Wet Shark and Flowers combinatorics math number theory probabilities Statement C Codeforces Round 341 (Div. 2) {621} PROGRAMMING 1700
611 Transforming Sequence combinatorics dp fft math Statement E AIM Tech Round (Div. 1) {623} PROGRAMMING AIM Tech Round Tutorial 3300
26806 Lucky Numbers combinatorics math Statement C Experimental Educational Round: VolBIT Formulas Blitz {630} PROGRAMMING 24160 1100
8040 Selection of Personnel combinatorics math Statement F Experimental Educational Round: VolBIT Formulas Blitz {630} PROGRAMMING Разбор задач Experimental Educational Round: VolBIT Formulas Blitz 1500
5655 Benches combinatorics math Statement H Experimental Educational Round: VolBIT Formulas Blitz {630} PROGRAMMING 24160 1700
3297 Challenge Pennants combinatorics math Statement G Experimental Educational Round: VolBIT Formulas Blitz {630} PROGRAMMING Разбор задач Experimental Educational Round: VolBIT Formulas Blitz 1800
8233 Parking Lot combinatorics math Statement I Experimental Educational Round: VolBIT Formulas Blitz {630} PROGRAMMING Разбор задач Experimental Educational Round: VolBIT Formulas Blitz 1900
966 Cowslip Collections combinatorics math number theory Statement F CROC 2016 - Elimination Round {645} PROGRAMMING Editorial for CROC 2016 Elimination Round 2500
642 Move by Prime combinatorics math number theory Statement G IndiaHacks 2016 - Online Edition (Div. 1 + Div. 2) {653} PROGRAMMING IndiaHacks Finals 2016 — Editorial 3000
4493 Robbers' watch brute force combinatorics dp math Statement A Codeforces Round 359 (Div. 1) {685} PROGRAMMING Codeforces Round #359 Editorial 1700
6161 Mike and Chocolate Thieves binary search combinatorics math Statement C Codeforces Round 361 (Div. 2) {689} PROGRAMMING 45912 1700
2212 PLEASE combinatorics dp implementation math matrices Statement C Codeforces Round 362 (Div. 1) {696} PROGRAMMING Codeforces Round #362 (Editorial) 2200
4954 Directed Roads combinatorics dfs and similar graphs math Statement D Codeforces Round 369 (Div. 2) {711} PROGRAMMING 46830 1900
1991 Memory and Scores combinatorics dp math Statement D Codeforces Round 370 (Div. 2) {712} PROGRAMMING Codeforces Round #370 Editorial 2100
451 Complete the Permutations combinatorics fft graphs math Statement E Codeforces Round 372 (Div. 1) {715} PROGRAMMING Codeforces Round #372 Editorial 3400
7958 Tennis Championship combinatorics constructive algorithms greedy math Statement C Codeforces Round 382 (Div. 2) {735} PROGRAMMING Codeforces Round #382 Editorial 1700
481 Igor and Interesting Numbers brute force combinatorics dp math Statement F Codeforces Round 387 (Div. 2) {747} PROGRAMMING 49171 2600
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
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
1121 Barrels and boxes brute force combinatorics math number theory probabilities Statement F Divide by Zero 2017 and Codeforces Round 399 (Div. 1 + Div. 2, combined) {768} PROGRAMMING Editorial Divide by Zero and Codeforces Round #399 (Div. 1+2, combined) 2300
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
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
10151 Minimum number of steps combinatorics greedy implementation math Statement B Codeforces Round 411 (Div. 1) {804} PROGRAMMING Codeforces Round #411 Editorial 1400
1600 Karen and Test brute force combinatorics constructive algorithms math Statement B Codeforces Round 419 (Div. 1) {815} PROGRAMMING Codeforces Round #419 Editorial 2200
6420 Makes And The Product combinatorics implementation math sortings Statement B Educational Codeforces Round 23 {817} PROGRAMMING 52638 1500
507 Ever-Hungry Krakozyabra brute force combinatorics greedy math Statement C Codeforces Round 426 (Div. 1) {833} PROGRAMMING Codeforces Round #426 Editorial 2600
1078 Prefix Sums binary search brute force combinatorics math matrices Statement F Educational Codeforces Round 26 {837} PROGRAMMING 53662 2500
3541 Winter is here combinatorics dp math number theory Statement D Codeforces Round 428 (Div. 2) {839} PROGRAMMING Codeforces Round #428 editorial 2200
7445 Leha and Function combinatorics greedy math number theory sortings Statement A Codeforces Round 429 (Div. 1) {840} PROGRAMMING Editorial 1300
9025 Rectangles combinatorics math Statement B AIM Tech Round 4 (Div. 2) {844} PROGRAMMING AIM Tech Round 4 -- Editorial 1300
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
652 Product transformation combinatorics math number theory Statement F Bubble Cup X - Finals [Online Mirror] {852} PROGRAMMING Tutorial 2300
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
163 Flowers and Chocolate combinatorics math matrices Statement G MemSQL Start[c]UP 3.0 - Round 2 (onsite finalists) {865} PROGRAMMING MemSQL Start[c]UP 3.0 Round 2 Editorial 3200
5188 The Intriguing Obsession combinatorics dp math Statement C Codeforces Round 439 (Div. 2) {869} PROGRAMMING Tutorial 1800
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
1109 Lust combinatorics math matrices Statement E Codeforces Round 446 (Div. 1) {891} PROGRAMMING Codeforces Round #446 Editorial 2800
4186 Counting Arrays combinatorics dp math number theory Statement E Educational Codeforces Round 33 (Rated for Div. 2) {893} PROGRAMMING 55989 2000
4692 Ralph And His Magic Field combinatorics constructive algorithms math number theory Statement B Codeforces Round 447 (Div. 2) {894} PROGRAMMING Codeforces Round #447 (Div.2 Only) Editorial 1800
7300 Square Subsets bitmasks combinatorics dp math Statement C Codeforces Round 448 (Div. 2) {895} PROGRAMMING Codeforces Round #448(Div.2) Editorial 2000
1234 String Mark combinatorics math strings Statement D Codeforces Round 448 (Div. 2) {895} PROGRAMMING Codeforces Round #448(Div.2) Editorial 2300
609 Nephren Runs a Cinema chinese remainder theorem combinatorics math number theory Statement D Codeforces Round 449 (Div. 1) {896} PROGRAMMING Codeforces Round #449 Editorial 2800
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
1980 List Of Integers binary search bitmasks brute force combinatorics math number theory Statement G Educational Codeforces Round 37 (Rated for Div. 2) {920} PROGRAMMING T 2300
1203 Красивая команда *special combinatorics math Statement C VK Cup 2018 - Квалификация 2 {929} PROGRAMMING Разбор VK Cup 2018 — Квалификация 2 2000
3422 Team Work combinatorics dp math Statement E ICM Technex 2018 and Codeforces Round 463 (Div. 1 + Div. 2, combined) {932} PROGRAMMING 57796 2400
388 A Creative Cutout brute force combinatorics math Statement D Codeforces Round 462 (Div. 1) {933} PROGRAMMING 57763 2900
1536 Max History combinatorics math Statement E Educational Codeforces Round 38 (Rated for Div. 2) {938} PROGRAMMING Educational Codeforces Round 38 — Editorial 2300
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
1593 Partitions combinatorics math number theory Statement G Educational Codeforces Round 41 (Rated for Div. 2) {961} PROGRAMMING Educational Codeforces Round 41 Editorial 2700
10557 Bus Video System combinatorics math Statement E Codeforces Round 481 (Div. 3) {978} PROGRAMMING T 1400
288 K Paths combinatorics data structures dp fft math Statement H Avito Code Challenge 2018 {981} PROGRAMMING Avito Code Challenge 2018 — разбор 2900
5042 Petr and Permutations combinatorics math Statement B Codeforces Round 485 (Div. 1) {986} PROGRAMMING Codeforces Round #485 Editorial 1800
3724 Bus Number brute force combinatorics math Statement E Codeforces Round 491 (Div. 2) {991} PROGRAMMING 60181 1800
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
2170 Sky Full of Stars combinatorics math Statement C Codeforces Round 493 (Div. 1) {997} PROGRAMMING 60357 2600
13039 Reorder the Array combinatorics data structures math sortings two pointers Statement A Codeforces Round 497 (Div. 1) {1007} PROGRAMMING Editorial for Codeforces Round #497 by Skyglow 1300
1037 Pave the Parallelepiped bitmasks brute force combinatorics math number theory Statement B Codeforces Round 497 (Div. 1) {1007} PROGRAMMING Editorial for Codeforces Round #497 by Skyglow 2400
3317 Intercity Travelling combinatorics math probabilities Statement E Educational Codeforces Round 47 (Rated for Div. 2) {1009} PROGRAMMING 60630 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
1851 Relatively Prime Powers combinatorics math number theory Statement F Educational Codeforces Round 50 (Rated for Div. 2) {1036} PROGRAMMING 61727 2400
1268 Maximum Reduction combinatorics data structures math Statement F Manthan, Codefest 18 (rated, Div. 1 + Div. 2) {1037} PROGRAMMING Tutorial 2400
4757 Mysterious Crime brute force combinatorics math meet-in-the-middle two pointers Statement D Codeforces Round 519 by Botan Investments {1043} PROGRAMMING Codeforces Round #519 Editorial 1700
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
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
7465 New Year and the Permutation Concatenation combinatorics dp math Statement D Good Bye 2018 {1091} PROGRAMMING Editorial 1700
11670 Substring Removal combinatorics math strings Statement B Educational Codeforces Round 57 (Rated for Div. 2) {1096} PROGRAMMING Разбор Educational Codeforces Round 57 1400
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
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
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
929 Serval and Bonus Problem combinatorics dp math probabilities Statement F Codeforces Round 551 (Div. 2) {1153} PROGRAMMING Editorial 2800
1886 Scalar Queries combinatorics data structures math sortings Statement F Educational Codeforces Round 65 (Rated for Div. 2) {1167} PROGRAMMING 67058 2300
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
13170 Tiles combinatorics greedy math Statement C Codeforces Global Round 4 {1178} PROGRAMMING E 1300
8193 Submarine in the Rybinsk Sea (easy edition) combinatorics math number theory Statement D1 Codeforces Round 574 (Div. 2) {1195} PROGRAMMING Разбор Codeforces Round #574 (Div. 2) 1500
4896 Submarine in the Rybinsk Sea (hard edition) combinatorics math number theory Statement D2 Codeforces Round 574 (Div. 2) {1195} PROGRAMMING Разбор Codeforces Round #574 (Div. 2) 1700
5455 Print a 1337-string... combinatorics constructive algorithms math strings Statement D Educational Codeforces Round 70 (Rated for Div. 2) {1202} PROGRAMMING 68972 1900
2046 Natasha, Sasha and the Prefix Sums combinatorics dp math number theory Statement E Codeforces Round 581 (Div. 2) {1204} PROGRAMMING 69244 2400
1916 Wrong Answer on test 233 (Hard Version) combinatorics math Statement F2 Technocup 2020 - Elimination Round 3 {1227} PROGRAMMING Разбор задач №2 2400
3444 Another Filling the Grid combinatorics dp math Statement E Codeforces Round 589 (Div. 2) {1228} PROGRAMMING 70162 2300
12043 Alice and the List of Presents combinatorics math Statement B Codeforces Round 593 (Div. 2) {1236} PROGRAMMING 70654 1400
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
2142 Key Storage combinatorics math Statement K 2019-2020 ICPC, NERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1267} PROGRAMMING nerc-2019-tutorial.pdf 2200
3706 Common Number binary search combinatorics dp math Statement E Codeforces Round 608 (Div. 2) {1271} PROGRAMMING 72247 2100
1776 Beautiful Rectangle brute force combinatorics constructive algorithms data structures greedy math Statement C Codeforces Round 606 (Div. 1, based on Technocup 2020 Elimination Round 4) {1276} PROGRAMMING Technocup 2020 — Elimination Round 4 + Codeforces Round 606: Editorial 2300
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
7241 Santa's Bot combinatorics math probabilities Statement D Educational Codeforces Round 79 (Rated for Div. 2) {1279} PROGRAMMING Educational Codeforces Round 79 Editorial 1700
93 Intergalactic Sliding Puzzle combinatorics constructive algorithms math Statement F Codeforces Round 607 (Div. 1) {1280} PROGRAMMING Codeforces Round #607 Editorial 3400
8724 New Year and Permutation combinatorics math Statement C Hello 2020 {1284} PROGRAMMING Hello 2020 Editorial 1700
1377 New Year and Castle Construction combinatorics geometry math sortings Statement E Hello 2020 {1284} PROGRAMMING Hello 2020 Editorial 2500
22262 JOE is on TV! combinatorics greedy math Statement B Codeforces Round 614 (Div. 2) {1293} PROGRAMMING 750.0 Codeforces Round #614 Editorial 1000
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
9860 Ayoub's function binary search combinatorics greedy math strings Statement C Codeforces Round 619 (Div. 2) {1301} PROGRAMMING 1250.0 Codeforces Round #619 (Div. 2) Editorial 1700
18670 Kuroni and Impossible Calculation brute force combinatorics math number theory Statement C Ozon Tech Challenge 2020 (Div.1 + Div.2, Rated, T-shirts + prizes!) {1305} PROGRAMMING 1250.0 Ozon Tech Challenge 2020 Editorial 1600
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
10489 Count the Arrays combinatorics math Statement D Educational Codeforces Round 83 (Rated for Div. 2) {1312} PROGRAMMING 74640
16382 Permutation Partitions combinatorics greedy math Statement C Codeforces Global Round 7 {1326} PROGRAMMING 1000.0 74961 1300
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
31976 K-th Beautiful String combinatorics implementation math Statement B Codeforces Round 629 (Div. 3) {1328} PROGRAMMING 75246 1300
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
4300 Height All the Same combinatorics constructive algorithms math matrices Statement E Codeforces Round 630 (Div. 2) {1332} PROGRAMMING 1750.0 Codeforces Round #630 Editorial 2100
3167 Divisor Paths combinatorics graphs greedy math number theory Statement E Educational Codeforces Round 85 (Rated for Div. 2) {1334} PROGRAMMING Educational Codeforces Round 85 Editorial
826 Chiori and Doll Picking (easy version) bitmasks brute force combinatorics math Statement E1 Codeforces Round 635 (Div. 1) {1336} PROGRAMMING 1750.0 Codeforces Round #635 Editorial 2600
480 Chiori and Doll Picking (hard version) bitmasks brute force combinatorics math Statement E2 Codeforces Round 635 (Div. 1) {1336} PROGRAMMING 1500.0 Codeforces Round #635 Editorial 3400
3536 Placing Rooks combinatorics fft math Statement E Educational Codeforces Round 86 (Rated for Div. 2) {1342} PROGRAMMING 76633 2300
6722 Modular Stability combinatorics math number theory Statement E Educational Codeforces Round 88 (Rated for Div. 2) {1359} PROGRAMMING Educational Codeforces Round 88 Editorial 2000
1413 Secure Password bitmasks combinatorics constructive algorithms interactive math Statement G Codeforces Round 648 (Div. 2) {1365} PROGRAMMING 3000.0 Editorial — Codeforces Round #648 2800
5523 Asterism (Easy Version) brute force combinatorics implementation math number theory sortings Statement E1 Codeforces Round 654 (Div. 2) {1371} PROGRAMMING 1500.0 Codeforces Round #654 (Div. 2) Editorial
9538 Unmerge combinatorics dp two pointers Statement B Codeforces Round 658 (Div. 1) {1381} PROGRAMMING 1500.0 Codeforces Round #658 Editorial 1800
15992 Cyclic Permutations combinatorics graphs math Statement C Codeforces Round 663 (Div. 2) {1391} PROGRAMMING 1250.0 Codeforces Round #663 (Div. 2) Editorial
983 ZS Shuffles Cards combinatorics math probabilities Statement H Codeforces Global Round 10 {1392} PROGRAMMING 3500.0 Codeforces Global Round 10 — Editorial
1152 Mercenaries bitmasks combinatorics data structures math two pointers Statement G Educational Codeforces Round 94 (Rated for Div. 2) {1400} PROGRAMMING 81942
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
2183 Expected Damage binary search combinatorics math probabilities Statement E Educational Codeforces Round 95 (Rated for Div. 2) {1418} PROGRAMMING Unofficial Editorial for Educational Round 95 (Div. 2)
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
19805 Two Round Dances combinatorics math Statement E Codeforces Round 677 (Div. 3) {1433} PROGRAMMING Codeforces Round #677 (Div. 3) Editorial
621 Sum Over Subsets combinatorics math number theory Statement F Codeforces Round 678 (Div. 2) {1436} PROGRAMMING 3000.0 Codeforces Round #678 (Div. 2). Editorial
1602 Emotional Fishermen combinatorics dp math Statement F Educational Codeforces Round 97 (Rated for Div. 2) {1437} PROGRAMMING 84149
1540 Long Permutation brute force combinatorics math Statement E Codeforces Round 681 (Div. 2, based on VK Cup 2019-2020 - Final) {1443} PROGRAMMING 2500.0 VK Cup 2019-2020 -- Engine Editorial
6765 Divide and Sum combinatorics math Statement B Codeforces Round 680 (Div. 1, based on Moscow Team Olympiad) {1444} PROGRAMMING 1000.0 Codeforces Round #680 Editorial
512 Multithreading (Easy Version) combinatorics fft math Statement H1 Codeforces Global Round 12 {1450} PROGRAMMING 2750.0 Codeforces Global Round 12 Editorial
277 Multithreading (Hard Version) combinatorics implementation math Statement H2 Codeforces Global Round 12 {1450} PROGRAMMING 1750.0 Codeforces Global Round 12 Editorial
8668 Radio Towers combinatorics dp math Statement D Educational Codeforces Round 98 (Rated for Div. 2) {1452} PROGRAMMING 84847
11337 Close Tuples (hard version) binary search combinatorics implementation math sortings two pointers Statement E2 Codeforces Round 690 (Div. 3) {1462} PROGRAMMING Codeforces Round #690 (Div. 3) Editorial
15198 Close Tuples (easy version) binary search combinatorics math sortings two pointers Statement E1 Codeforces Round 690 (Div. 3) {1462} PROGRAMMING Codeforces Round #690 (Div. 3) Editorial
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
454 Tiles combinatorics dp fft math Statement G Educational Codeforces Round 102 (Rated for Div. 2) {1473} PROGRAMMING Educational Codeforces Round 102 Editorial
27043 Ball in Berland combinatorics dfs and similar graphs hashing math Statement C Codeforces Round 697 (Div. 3) {1475} PROGRAMMING Codeforces Round #697 (Div. 3) Editorial
17561 Advertising Agency combinatorics implementation math sortings Statement E Codeforces Round 697 (Div. 3) {1475} PROGRAMMING Codeforces Round #697 (Div. 3) Editorial
163 Nezzar and Chocolate Bars combinatorics fft math probabilities Statement F Codeforces Round 698 (Div. 1) {1477} PROGRAMMING 4000.0 87294 3500
699 String Counting combinatorics dp math Statement G Educational Codeforces Round 104 (Rated for Div. 2) {1487} PROGRAMMING 87873
1530 BFS Trees combinatorics dfs and similar graphs math shortest paths trees Statement D Codeforces Round 706 (Div. 1) {1495} PROGRAMMING 2000.0 Codeforces Round #706 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
1675 Cost Equilibrium combinatorics constructive algorithms math sortings Statement E Divide by Zero 2021 and Codeforces Round 714 (Div. 2) {1513} PROGRAMMING 2750.0 Divide by Zero 2021 and Codeforces Round #714 (Div. 2) Editorial
34691 AND 0, Sum Big bitmasks combinatorics math Statement B Codeforces Round 716 (Div. 2) {1514} PROGRAMMING 1000.0 Codeforces round #716 editorial
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
2365 Assimilation IV combinatorics dp math probabilities Statement E Educational Codeforces Round 109 (Rated for Div. 2) {1525} PROGRAMMING 90793
1413 Oolimry and Suffix Array combinatorics constructive algorithms math string suffix structures Statement E Codeforces Round 723 (Div. 2) {1526} PROGRAMMING 2500.0 Codeforces Round #723 (Div. 2) Editorial
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
337 AmShZ Farm combinatorics fft math Statement F Codeforces Round 722 (Div. 1) {1528} PROGRAMMING 3000.0 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
2730 Omkar and Forest combinatorics graphs math shortest paths Statement E Codeforces Round 724 (Div. 2) {1536} PROGRAMMING 2250.0 Codeforces Round #724 — Editorial 2300
1099 Omkar and Akmar combinatorics games math Statement F Codeforces Round 724 (Div. 2) {1536} PROGRAMMING 2500.0 Codeforces Round #724 — Editorial 2600
21506 Contest Start combinatorics geometry math Statement A Codeforces Round 727 (Div. 2) {1539} PROGRAMMING 500.0 tutorial 1000
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
24456 Customising the Track combinatorics greedy math Statement B Codeforces Round 730 (Div. 2) {1543} PROGRAMMING 750.0 Codeforces Round #730 (Div. 2) Editorial
6736 AquaMoon and Chess combinatorics math Statement B Codeforces Round 732 (Div. 1) {1545} PROGRAMMING 1000.0 Codeforces Round #732 Editorial 1900
2015 The Three Little Pigs combinatorics dp fft math Statement C Codeforces Round 736 (Div. 1) {1548} PROGRAMMING 1750.0 Codeforces Round 736 Editorial
2055 Excellent Arrays brute force combinatorics constructive algorithms implementation math Statement D Educational Codeforces Round 111 (Rated for Div. 2) {1550} PROGRAMMING Educational Codeforces Round 111 Editorial
3767 Permutation Shift brute force combinatorics constructive algorithms dfs and similar graphs math Statement E Harbour.Space Scholarship Contest 2021-2022 (open for everyone, rated, Div. 1 + Div. 2) {1553} PROGRAMMING 1750.0 Harbour.Space Scholarship Contest 2021-2022 (Div. 1 + Div. 2) Editorial
311 Stairs combinatorics divide and conquer fft math Statement I Harbour.Space Scholarship Contest 2021-2022 (open for everyone, rated, Div. 1 + Div. 2) {1553} PROGRAMMING 5250.0 Harbour.Space Scholarship Contest 2021-2022 (Div. 1 + Div. 2) Editorial
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
13319 Jury Meeting combinatorics math Statement C Educational Codeforces Round 113 (Rated for Div. 2) {1569} PROGRAMMING 94721
18208 Combinatorics Homework combinatorics greedy math Statement B 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
33073 Luntik and Subsequences combinatorics math Statement B Codeforces Round 750 (Div. 2) {1582} PROGRAMMING 750.0 Codeforces Round #750 (Div.2) Editorial
3983 Guess the Permutation binary search combinatorics interactive math Statement D Technocup 2022 - Elimination Round 2 {1584} PROGRAMMING 1500.0 Editorial for Technocup 2022 — Elimination Round 2 and Codeforces Round #755 (Div. 1, Div. 2) 2000
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
298 Omkar and Mosaic combinatorics constructive algorithms math Statement I Codeforces Round 749 (Div. 1 + Div. 2, based on Technocup 2022 Elimination Round 1) {1586} PROGRAMMING 4000.0 Editorial for Technocup 2022 — Elimination Round 1 and Codeforces Round #749 (Div. 1+Div. 2)
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
12173 Rubik's Cube Coloring (easy version) combinatorics math Statement E1 Codeforces Round 747 (Div. 2) {1594} PROGRAMMING 1000.0 95525 1300
10438 Training Session combinatorics math Statement D Educational Codeforces Round 115 (Rated for Div. 2) {1598} PROGRAMMING 95890
1959 Bubble Strike combinatorics math probabilities ternary search Statement C Bubble Cup 14 - Finals Online Mirror (Unrated, ICPC Rules, Teams Preferred, Div. 1) {1599} PROGRAMMING BubbleCup2021.pdf
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
1550 Dominoes combinatorics fft graphs math Statement D Codeforces Round 758 (Div.1 + Div. 2) {1608} PROGRAMMING 1500.0 Editorial of Codeforces Round #758 (Div.1 + Div. 2)
3003 Not Quite Lee combinatorics math number theory Statement D Codeforces Global Round 17 {1610} PROGRAMMING 2250.0 Codeforces Global Round 17 Editorial
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
4634 Shuffle combinatorics math two pointers Statement D Educational Codeforces Round 120 (Rated for Div. 2) {1622} PROGRAMMING Educational Codeforces Round 120 Editorial
900 A Random Code Problem combinatorics dp math number theory Statement F Educational Codeforces Round 121 (Rated for Div. 2) {1626} PROGRAMMING 99136
3487 Expand the Path brute force combinatorics implementation math Statement E Educational Codeforces Round 123 (Rated for Div. 2) {1644} PROGRAMMING 100227
427 Basis combinatorics fft math number theory Statement F Educational Codeforces Round 123 (Rated for Div. 2) {1644} PROGRAMMING 100227
18633 Weird Sum combinatorics data structures geometry math matrices sortings Statement A Codeforces Round 775 (Div. 1, based on Moscow Open Olympiad in Informatics) {1648} PROGRAMMING 500.0 Codeforces Round #775 Editorial
100 Three Minimums combinatorics fft math Statement H Codeforces Round 778 (Div. 1 + Div. 2, based on Technocup 2022 Final Round) {1654} PROGRAMMING 4000.0 Editorial of Codeforces Round #778 (Div. 1 + Div. 2, based on Technocup 2022 Final Round) 3500