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69294 Die Roll math probabilities Statement A Codeforces Beta Round 9 (Div. 2 Only) {9} PROGRAMMING Codeforces Beta Round #9 tutorial 1000
6504 Fish bitmasks dp probabilities Statement E Codeforces Beta Round 16 (Div. 2 Only) {16} PROGRAMMING Codeforces Beta Round #16 Tutorial 2100
2626 Broken robot dp probabilities Statement D Codeforces Beta Round 24 {24} PROGRAMMING Codeforces Beta Round #24 solutions 2400
928 Tickets combinatorics math probabilities Statement D Codeforces Beta Round 26 (Codeforces format) {26} PROGRAMMING Разбор Codeforces Beta Round #26 (ещё один) 2800
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
2363 Shooting Gallery dp probabilities Statement C Codeforces Beta Round 30 (Codeforces format) {30} PROGRAMMING Codeforces Beta Round #30. Разбор C 1800
705 Bombing binary search dp probabilities Statement D Codeforces Beta Round 47 {50} PROGRAMMING Codeforces #47 problem solutions 2100
1627 First Digit Law dp math probabilities Statement C Codeforces Beta Round 50 {54} PROGRAMMING Codeforces Beta Round #50: Editorial for problem E 2000
531 Half-decay tree data structures divide and conquer dp math probabilities Statement D Codeforces Beta Round 62 {68} PROGRAMMING 2400
2861 Falling Anvils math probabilities Statement B Codeforces Beta Round 69 (Div. 1 Only) {77} PROGRAMMING Codeforces Beta Round #69 tutorial 1800
614 Petya and Tree binary search dfs and similar probabilities sortings trees Statement C Yandex.Algorithm 2011: Round 1 {85} PROGRAMMING Yandex.Algorithm 2011 - Round 1. Problem C. Tutorial 2200
558 Help Shrek and Donkey dp games math probabilities Statement E Codeforces Beta Round 78 (Div. 1 Only) {98} PROGRAMMING Editorial 2500
152 Help King implementation probabilities trees Statement B Codeforces Beta Round 78 (Div. 1 Only) {98} PROGRAMMING 2600
790 Castle dp greedy probabilities sortings trees Statement D Codeforces Beta Round 79 (Div. 1 Only) {101} PROGRAMMING Codeforces Beta Round 79, editoral 2300
905 Dark Assembly brute force probabilities Statement B Codeforces Beta Round 81 {105} PROGRAMMING Tutorial 1800
4243 Basketball Team combinatorics dp math probabilities Statement B Codeforces Beta Round 83 (Div. 1 Only) {107} PROGRAMMING Tutorial 1700
151 Darts geometry probabilities Statement E Codeforces Beta Round 83 (Div. 1 Only) {107} PROGRAMMING Tutorial 2600
1767 Lucky Probability brute force probabilities Statement B Codeforces Beta Round 84 (Div. 1 Only) {109} PROGRAMMING Tutorial 2000
811 Museum math matrices probabilities Statement D Codeforces Beta Round 86 (Div. 1 Only) {113} PROGRAMMING Codeforces Beta Round #86 Editorial 2500
802 Maze dfs and similar dp probabilities trees Statement E Codeforces Beta Round 92 (Div. 1 Only) {123} PROGRAMMING Codeforces Beta Round #92 - Analysis 2600
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
8845 Bag of mice dp games math probabilities Statement D Codeforces Round 105 (Div. 2) {148} PROGRAMMING Codeforces Round #105 (Div. 2): editorial 1900
742 Smart Cheater data structures math probabilities Statement C Codeforces Round 107 (Div. 1) {150} PROGRAMMING Tutorial 2300
2443 Wizards and Huge Prize dp math probabilities Statement B Codeforces Round 114 (Div. 1) {167} PROGRAMMING Codeforces Round #114 — Tutorial 2000
317 Plane of Tanks: Duel brute force dp math probabilities Statement D Codeforces Round 115 {175} PROGRAMMING Codeforces Round #115 — editorial A-E 2400
480 T-shirt dp greedy probabilities Statement D Croc Champ 2012 - Final {183} PROGRAMMING CROC Champ 2012 — Round 3 (Editorial) 2800
1232 Little Elephant and Furik and Rubik math probabilities Statement C Codeforces Round 129 (Div. 1) {204} PROGRAMMING Tutorial 2200
524 Gifts combinatorics dp math probabilities Statement E Codeforces Round 142 (Div. 1) {229} PROGRAMMING Codeforces Round #142 Problem Analysis 2500
4285 Let's Play Osu! dp math probabilities Statement B Codeforces Round 146 (Div. 1) {235} PROGRAMMING Codeforces Round #146 Tutorial 2100
639 Piglet's Birthday dp math probabilities Statement E Codeforces Round 152 (Div. 2) {248} PROGRAMMING Разбор задач Codeforces Round #152 2700
1414 Little Elephant and Broken Sorting dp math probabilities Statement D Codeforces Round 157 (Div. 1) {258} PROGRAMMING Codeforces Round #157 — Editorial 2600
1600 Maxim and Restaurant dp math probabilities Statement B Codeforces Round 160 (Div. 1) {261} PROGRAMMING Codeforces Round #160 tutorial 2100
1135 Playlist math probabilities sortings Statement E Codeforces Round 164 (Div. 2) {268} PROGRAMMING Codeforces Round #164 (Div. 2) — Problems Analysis 2100
372 Google Code Jam dp probabilities Statement D Codeforces Round 170 (Div. 1) {277} PROGRAMMING Codeforces Round #170 Tutorial 2700
5081 Game on Tree implementation math probabilities trees Statement C Codeforces Round 172 (Div. 1) {280} PROGRAMMING T 2400
261 Ksusha and Square geometry math probabilities two pointers Statement D Croc Champ 2013 - Round 2 {293} PROGRAMMING Croc Champ 2013 — Round 2 — Editorial 2700
383 Random Ranking dp math probabilities Statement E Codeforces Round 183 (Div. 1) {303} PROGRAMMING Codeforces Round #183 Editorial 2800
13324 Archer math probabilities Statement B Codeforces Round 185 (Div. 2) {312} PROGRAMMING Codeforces Round #185 Editorial 1300
241 Counting Skyscrapers dp math probabilities Statement E MemSQL start[c]up Round 2 - online version {335} PROGRAMMING MemSQL start[c]up Round 2 -- Editorial 2900
531 Expecting Trouble *special probabilities Statement A Friday the 13th, Programmers Day {345} PROGRAMMING 1600
2721 Jeff and Furik combinatorics dp probabilities Statement B Codeforces Round 204 (Div. 1) {351} PROGRAMMING Codeforces Round #204 — tutorial 2100
2500 Ghd brute force math probabilities Statement D Codeforces Round 213 (Div. 1) {364} PROGRAMMING Codeforces Round #213 Editorial 2600
1283 Valera and Fools dfs and similar dp graphs shortest paths Statement D Codeforces Round 216 (Div. 2) {369} PROGRAMMING Editorial Codeforces Round #216 (Div. 2) 2300
1186 Painting The Wall dp probabilities Statement B Codeforces Round 233 (Div. 1) {398} PROGRAMMING 1000.0 Codeforces Round #233 Editorial
927 Square Table constructive algorithms math probabilities Statement E RCC 2014 Warmup (Div. 2) {417} PROGRAMMING RCC 2014 WarmUp Analysis 2400
149 Colored Jenga dfs and similar dp probabilities Statement E Codeforces Round 242 (Div. 2) {424} PROGRAMMING Codeforces Round #242 (Div. 2) Editorial 2500
815 Valera and Number bitmasks dp math probabilities Statement E Codeforces Round 252 (Div. 2) {441} PROGRAMMING Разбор Codeforces Round #252 (Div. 2) 2700
6082 Andrey and Problem greedy math probabilities Statement B Codeforces Round 253 (Div. 1) {442} PROGRAMMING Codeforces #253 editorial 1800
1155 DZY Loves FFT probabilities Statement B Codeforces Round 254 (Div. 1) {444} PROGRAMMING Codeforces Round #254 Editorial 2400
463 DZY Loves Games math matrices probabilities Statement D Codeforces Round #FF (Div. 1) {446} PROGRAMMING Codeforces Round #FF(255) Editorial 2800
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
12381 Little Pony and Expected Maximum probabilities Statement A Codeforces Round 259 (Div. 1) {453} PROGRAMMING Codeforces Round #259 Editorial 1600
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
756 World of Darkraft - 2 dp probabilities Statement D Codeforces Round 265 (Div. 1) {464} PROGRAMMING Codeforces Round #265 Editorial 2600
36817 Dreamoon and WiFi bitmasks brute force combinatorics dp math probabilities Statement B Codeforces Round 272 (Div. 2) {476} PROGRAMMING 1300
991 Game with Strings bitmasks dp probabilities Statement C Codeforces Round 275 (Div. 1) {482} PROGRAMMING Codeforces Round #275 Editorial 2800
956 Helping People dp probabilities Statement C Codeforces Round 282 (Div. 1) {494} PROGRAMMING 15148 2900
1294 Name That Tune dp probabilities two pointers Statement B Codeforces Round 284 (Div. 1) {498} PROGRAMMING Codeforces Round #284 Editorial 2500
1658 Second price auction bitmasks probabilities Statement C Rockethon 2015 {513} PROGRAMMING 16260 2000
722 Inversions problem dp probabilities Statement G2 Rockethon 2015 {513} PROGRAMMING 16260 2400
8129 Ilya and Escalator combinatorics dp math probabilities Statement D Codeforces Round 293 (Div. 2) {518} PROGRAMMING Codeforces Round #293 (Div.2) Editorial 1900
6474 Bad Luck Island dp probabilities Statement D Codeforces Round 301 (Div. 2) {540} PROGRAMMING Tutorial 2100
620 Kyoya and Train dp fft graphs math probabilities Statement E Codeforces Round 309 (Div. 1) {553} PROGRAMMING Codeforces Round #309 Editorial 3300
475 Randomizer combinatorics geometry probabilities Statement D Codeforces Round 313 (Div. 1) {559} PROGRAMMING Codeforces Round 313 — Extended editoral 2800
728 Wilbur and Trees dp math probabilities sortings Statement D Codeforces Round 331 (Div. 2) {596} PROGRAMMING Codeforces Round #331 Editorial 2500
1411 Kleofáš and the n-thlon dp math probabilities Statement C Codeforces Round 333 (Div. 1) {601} PROGRAMMING Codeforces Round #333 — editorial 2400
1544 Intergalaxy Trips probabilities shortest paths Statement E Codeforces Round 335 (Div. 1) {605} PROGRAMMING Codeforces Round #335 Problem Analysis 2600
271 Combining Slimes dp math matrices probabilities Statement G Wunder Fund Round 2016 (Div. 1 + Div. 2 combined) {618} PROGRAMMING Wunder Fund Round 2016 Editorials 3300
6218 Wet Shark and Flowers combinatorics math number theory probabilities Statement C Codeforces Round 341 (Div. 2) {621} PROGRAMMING 1700
554 Birthday greedy math probabilities Statement D AIM Tech Round (Div. 1) {623} PROGRAMMING 2600
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
620 Startup Funding binary search constructive algorithms data structures probabilities two pointers Statement E Manthan, Codefest 16 {633} PROGRAMMING Manthan, Codefest 16: Editorials 2400
1570 Little Artem and Random Variable dp implementation math probabilities Statement D VK Cup 2016 - Round 2 {641} PROGRAMMING VK Cup 2016 — Раунд 2 (editorial) 2300
698 Bear and Destroying Subtrees dp math probabilities trees Statement E VK Cup 2016 - Round 3 {643} PROGRAMMING VK Cup 2016 — Round 3 — Editorial 2600
584 Gambling Nim bitmasks math matrices probabilities Statement A CROC 2016 - Final Round [Private, For Onsite Finalists Only] {662} PROGRAMMING Editorial for CROC 2016 Finals and Codeforces Round #347 2400
2716 Another Sith Tournament bitmasks dp Statement E Educational Codeforces Round 13 {678} PROGRAMMING Editorial 2200
342 Bear and Chase brute force dfs and similar graphs implementation math probabilities Statement D Codeforces Round 356 (Div. 1) {679} PROGRAMMING Codeforces Round #356 — Editorial 2900
3794 Puzzles dfs and similar math probabilities trees Statement B Codeforces Round 362 (Div. 1) {696} PROGRAMMING Codeforces Round #362 (Editorial) 1800
1439 LRU bitmasks dp math probabilities Statement C Codeforces Round 363 (Div. 1) {698} PROGRAMMING Solution 2700
1359 ZS and The Birthday Paradox math number theory probabilities Statement E Codeforces Round 369 (Div. 2) {711} PROGRAMMING 46830 2400
694 Memory and Casinos data structures math probabilities Statement E Codeforces Round 370 (Div. 2) {712} PROGRAMMING Codeforces Round #370 Editorial 2700
1579 Dexterina’s Lab games matrices probabilities Statement D Bubble Cup 9 - Finals [Online Mirror] {717} PROGRAMMING Tutorial 1900
469 Pokermon League challenge math probabilities Statement H Bubble Cup 9 - Finals [Online Mirror] {717} PROGRAMMING Tutorial 2400
2617 Gosha is hunting brute force data structures dp flows math probabilities sortings Statement E Codeforces Round 381 (Div. 1) {739} PROGRAMMING 48582 2900
1255 Inversions After Shuffle data structures probabilities Statement E Codeforces Round 388 (Div. 2) {749} PROGRAMMING Tutorial 2600
3417 Jon and Orbs dp math probabilities Statement D 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) 2100
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
153 Marmots (hard) math probabilities Statement D3 Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} PROGRAMMING helvetic-coding-contest-2017-editorial.pdf 2800
151 Marmots (hard) math probabilities Statement F Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} PROGRAMMING helvetic-coding-contest-2017-editorial.pdf 2800
20001 Journey dfs and similar dp graphs probabilities trees Statement C Codeforces Round 428 (Div. 2) {839} PROGRAMMING Codeforces Round #428 editorial 1500
3936 Destiny data structures probabilities Statement D Codeforces Round 429 (Div. 1) {840} PROGRAMMING Editorial 2400
2569 Interactive LowerBound brute force interactive probabilities Statement B AIM Tech Round 4 (Div. 1) {843} PROGRAMMING AIM Tech Round 4 -- Editorial 2000
2641 Random Query data structures math probabilities two pointers Statement F Educational Codeforces Round 28 {846} PROGRAMMING 54357 2000
1121 Third Month Insanity dp probabilities trees Statement D MemSQL Start[c]UP 3.0 - Round 1 {859} PROGRAMMING Tutorial 2100
1291 Something with XOR Queries brute force interactive probabilities Statement D Technocup 2018 - Elimination Round 2 {870} PROGRAMMING Editorial Codeforces Round 440 Div.1+Div.2 (and Technocup 2018 — Elimination Round 2) 2100
1264 Eyes Closed data structures probabilities Statement E Codeforces Round 448 (Div. 2) {895} PROGRAMMING Codeforces Round #448(Div.2) Editorial 2500
4391 Willem, Chtholly and Seniorious data structures probabilities Statement C Codeforces Round 449 (Div. 1) {896} PROGRAMMING Codeforces Round #449 Editorial 2700
2600 New Year and Arbitrary Arrangement dp math probabilities Statement D Good Bye 2017 {908} PROGRAMMING Good Bye 2017 Editorial 2200
2138 Fishes data structures graphs greedy probabilities shortest paths Statement D Codeforces Round 456 (Div. 2) {912} PROGRAMMING Codeforces Round #456 (Div. 2) Editorial 2100
764 Strongly Connected Tournament dp graphs math probabilities Statement F Hello 2018 {913} PROGRAMMING Tutorial 2700
141 Don't Exceed math probabilities Statement H Hello 2018 {913} PROGRAMMING Tutorial 3400
3102 Game with String implementation probabilities strings Statement B Codeforces Round 468 (Div. 1, based on Technocup 2018 Final Round) {930} PROGRAMMING Codeforces Round #468 and Technocup 2018 Final Round Analysis 1800
2805 Fafa and Ancient Alphabet math probabilities Statement D Codeforces Round 465 (Div. 2) {935} PROGRAMMING 1900
63 Astronomy geometry probabilities Statement F Codeforces Round 469 (Div. 1) {949} PROGRAMMING 58291 3200
2564 I'm Feeling Lucky! probabilities Statement D April Fools Contest 2018 {952} PROGRAMMING April Fools Day Contest 2018: editorial 2000
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
649 Circles of Waiting math Statement E Tinkoff Internship Warmup Round 2018 and Codeforces Round 475 (Div. 1) {963} PROGRAMMING Editorial Tinkoff Internship Warmup Round 2018 and Codeforces Round #475 (Div. 1 + Div. 2) 3100
278 A Trance of Nightfall dp geometry matrices probabilities Statement E Codeforces Round 487 (Div. 2) {989} PROGRAMMING Codeforces Round #487 (Div. 2) Editorial 2900
3317 Intercity Travelling combinatorics math probabilities Statement E Educational Codeforces Round 47 (Rated for Div. 2) {1009} PROGRAMMING 60630 1900
2582 Subway Pursuit binary search interactive probabilities Statement B Codeforces Round 507 (Div. 1, based on Olympiad of Metropolises) {1039} PROGRAMMING 61668 2100
2077 Vasya and Magic Matrix dp math probabilities Statement E Codeforces Round 510 (Div. 2) {1042} PROGRAMMING Tutorial 2300
856 Interstellar battle math probabilities trees Statement D Bubble Cup 11 - Finals [Online Mirror, Div. 1] {1045} PROGRAMMING Tutorial (PDF) 2600
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
885 Lost Root interactive probabilities Statement F Codeforces Round 523 (Div. 2) {1061} PROGRAMMING Tutorial (en) 2400
490 Computer Game dp greedy math probabilities Statement D Codeforces Round 518 (Div. 1) [Thanks, Mail.Ru!] {1067} PROGRAMMING Tutorial 2800
433 Mergesort Strikes Back math probabilities Statement G Avito Cool Challenge 2018 {1081} PROGRAMMING 63888 3000
2057 Inversion Expectation dp math probabilities Statement F Educational Codeforces Round 57 (Rated for Div. 2) {1096} PROGRAMMING Разбор Educational Codeforces Round 57 2300
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
3163 Makoto and a Blackboard dp math number theory probabilities Statement D Hello 2019 {1097} PROGRAMMING 64310 2200
3181 Arithmetic Progression binary search interactive number theory probabilities Statement E Codeforces Round 538 (Div. 2) {1114} PROGRAMMING Codeforces Round #538 (Div. 2) Editorial 2100
2694 Steps to One dp math number theory probabilities Statement D Codeforces Round 548 (Div. 2) {1139} PROGRAMMING Codeforces Round #548 Editorial 2300
387 Gold Experience constructive algorithms graphs math number theory probabilities Statement G Codeforces Global Round 3 {1148} PROGRAMMING Codeforces Global Round 3 Editorial 3100
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
1712 Card Bag dp math probabilities Statement F Educational Codeforces Round 64 (Rated for Div. 2) {1156} PROGRAMMING 66827 2500
1225 Nauuo and Pictures (easy version) dp probabilities Statement C1 Codeforces Round 564 (Div. 1) {1172} PROGRAMMING Codeforces Round #564 Editorial 2500
995 Nauuo and Pictures (hard version) dp probabilities Statement C2 Codeforces Round 564 (Div. 1) {1172} PROGRAMMING Codeforces Round #564 Editorial 2700
128 Parallel Universes (Hard) math matrices Statement D2 Helvetic Coding Contest 2019 online mirror (teams allowed, unrated) {1184} PROGRAMMING helvetic-coding-contest-2019-editorial.pdf 3300
1110 Expected Square Beauty dp math probabilities Statement F Educational Codeforces Round 67 (Rated for Div. 2) {1187} PROGRAMMING Разбор Educational Codeforces Round 67 2600
108 Tokitsukaze and Powers number theory probabilities Statement F Codeforces Round 573 (Div. 1) {1190} PROGRAMMING E 3300
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
1075 GCD Groups 2 greedy number theory probabilities Statement F Codeforces Round 576 (Div. 1) {1198} PROGRAMMING E 2900
348 Marek and Matching (easy version) brute force probabilities Statement F1 Dasha Code Championship - SPb Finals Round (only for onsite-finalists) {1210} PROGRAMMING Dasha Code Championship Finals and Mirror Round 588 Editorial 2900
426 Marek and Matching (hard version) brute force probabilities Statement F2 Dasha Code Championship - SPb Finals Round (only for onsite-finalists) {1210} PROGRAMMING Dasha Code Championship Finals and Mirror Round 588 Editorial 3100
211 Alice and the Cactus dfs and similar graphs math probabilities Statement F Codeforces Round 593 (Div. 2) {1236} PROGRAMMING 70654 2900
1364 Hyakugoku and Ladders dp probabilities shortest paths Statement E Codeforces Round 597 (Div. 2) {1245} PROGRAMMING Codeforces Round #597 (Div. 2) Editorial 2300
1524 Tree Queries data structures probabilities trees Statement D Codeforces Round 601 (Div. 1) {1254} PROGRAMMING Codeforces Round #601 Editorial 2600
1318 Beautiful Mirrors with queries data structures probabilities Statement C Codeforces Round 604 (Div. 1) {1264} PROGRAMMING 71995 2400
1524 Beautiful Bracket Sequence (easy version) combinatorics dp probabilities Statement D1 Codeforces Round 604 (Div. 1) {1264} PROGRAMMING 71995 2600
1314 Beautiful Bracket Sequence (hard version) combinatorics probabilities Statement D2 Codeforces Round 604 (Div. 1) {1264} PROGRAMMING 71995 3000
4492 Beautiful Mirrors data structures dp math probabilities Statement E Codeforces Round 604 (Div. 2) {1265} PROGRAMMING Codeforces Round #604 Editorial 2100
825 Game Relics math probabilities Statement G 2019-2020 ICPC, NERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1267} PROGRAMMING nerc-2019-tutorial.pdf 3100
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
727 LCC data structures math matrices probabilities Statement D Codeforces Round 612 (Div. 1) {1286} PROGRAMMING Codeforces Round #612 - Editorial 2900
1507 Good Contest combinatorics dp probabilities Statement F Educational Codeforces Round 81 (Rated for Div. 2) {1295} PROGRAMMING Educational Codeforces Round 81 Editorial 2600
3227 Kuroni and the Punishment math number theory probabilities Statement F Ozon Tech Challenge 2020 (Div.1 + Div.2, Rated, T-shirts + prizes!) {1305} PROGRAMMING 2500.0 Ozon Tech Challenge 2020 Editorial 2500
1964 Tourism brute force dp graphs probabilities Statement D VK Cup 2019-2020 - Elimination Round (Engine) {1310} PROGRAMMING 2250.0 VK Cup 2019-2020 - Elimination Round (Engine) and Codeforces Round #623 2300
893 Battalion Strength data structures divide and conquer probabilities Statement F CodeCraft-20 (Div. 2) {1316} PROGRAMMING 2500.0 Codecraft-20 (Div.2) Editorial 2800
101 Nastya and Bees graphs interactive probabilities Statement E Codeforces Round 637 (Div. 1) - Thanks, Ivan Belonogov! {1340} PROGRAMMING 2250.0 Codeforces Round #637 Editorial
1046 Slime and Biscuits math probabilities Statement D Codeforces Round 641 (Div. 1) {1349} PROGRAMMING 2000.0 Codeforces Round #641 Editorial 3200
952 Find a Gift binary search interactive probabilities Statement G Educational Codeforces Round 87 (Rated for Div. 2) {1354} PROGRAMMING 77593 2600
984 James and the Chase dfs and similar graphs probabilities trees Statement E Codeforces Round 647 (Div. 1) - Thanks, Algo Muse! {1361} PROGRAMMING 3000.0 Codeforces Round #647 Editorial 3000
1546 X-OR bitmasks constructive algorithms interactive probabilities Statement E Codeforces Round 649 (Div. 2) {1364} PROGRAMMING 2500.0 Codeforces round #649 editorial 2700
932 Circular Dungeon greedy math probabilities Statement G Educational Codeforces Round 91 (Rated for Div. 2) {1380} PROGRAMMING Educational Codeforces Round 91 Editorial
983 ZS Shuffles Cards combinatorics math probabilities Statement H Codeforces Global Round 10 {1392} PROGRAMMING 3500.0 Codeforces Global Round 10 — Editorial
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)
8802 Bargain dp math probabilities Statement C Codeforces Round 675 (Div. 2) {1422} PROGRAMMING 1000.0 Codeforces Round #675 (Div. 2) Editorial
4434 Checkpoints brute force constructive algorithms greedy math probabilities Statement D Codeforces Round 688 (Div. 2) {1453} PROGRAMMING 2000.0 Codeforces Round #688 (Div. 2) Editorial
43952 Special Permutation constructive algorithms probabilities Statement A Codeforces Round 686 (Div. 3) {1454} PROGRAMMING Codeforces Round #686 (Div. 3) Editorial
17644 Red-Blue Shuffle math probabilities Statement A Codeforces Round 691 (Div. 2) {1459} PROGRAMMING 750.0 Codeforces Round #691 Editorial (finished)
12405 Random Events math probabilities Statement C Codeforces Round 689 (Div. 2, based on Zed Code Competition) {1461} PROGRAMMING 1250.0 Codeforces Round #689 (Div. 2). Editorial
1436 Strange Shuffle binary search brute force constructive algorithms interactive probabilities Statement C Codeforces Round 694 (Div. 1) {1470} PROGRAMMING 1000.0 86464
163 Nezzar and Chocolate Bars combinatorics fft math probabilities Statement F Codeforces Round 698 (Div. 1) {1477} PROGRAMMING 4000.0 87294 3500
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
264 School Clubs dp fft math number theory probabilities Statement E Codeforces Round 700 (Div. 1) {1479} PROGRAMMING 4000.0 Editorial of Codeforces Round #700
2110 Two Houses brute force combinatorics graphs interactive probabilities sortings Statement E CodeCraft-21 and Codeforces Round 711 (Div. 2) {1498} PROGRAMMING 2500.0 CodeCraft-21 and Codeforces Round #711 (Div. 2) Editorial
583 Is It Rated? greedy interactive math probabilities Statement I 2020-2021 ICPC, NERC, Northern Eurasia Onsite (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1510} PROGRAMMING nerc-2020-offline-tutorial.pdf
4803 Cut and Stick binary search data structures greedy probabilities sortings Statement D Codeforces Round 716 (Div. 2) {1514} PROGRAMMING 2000.0 Codeforces round #716 editorial
2469 Love-Hate bitmasks brute force dp probabilities Statement D Deltix Round, Spring 2021 (open for everyone, rated, Div. 1 + Div. 2) {1523} PROGRAMMING 2250.0 Deltix Round, Spring 2021. Editorial 2400
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
388 Median Queries constructive algorithms interactive probabilities Statement F Codeforces Round 723 (Div. 2) {1526} PROGRAMMING 3500.0 Codeforces Round #723 (Div. 2) Editorial
985 Bingo bitmasks dp probabilities Statement F Codeforces Round 733 (Div. 1 + Div. 2, based on VK Cup 2021 - Elimination (Engine)) {1530} PROGRAMMING 2750.0 Codeforces Round #733 Editorial (all problems)
10073 Secret Santa constructive algorithms flows graphs math probabilities Statement D Codeforces Round 733 (Div. 1 + Div. 2, based on VK Cup 2021 - Elimination (Engine)) {1530} PROGRAMMING 1500.0 Codeforces Round #733 Editorial (all problems)
2983 Tree Array brute force combinatorics dp math probabilities trees Statement B Codeforces Round 728 (Div. 1) {1540} PROGRAMMING 1250.0 Tutorial
5605 Need for Pink Slips brute force dfs and similar implementation math probabilities Statement C Codeforces Round 730 (Div. 2) {1543} PROGRAMMING 1500.0 Codeforces Round #730 (Div. 2) Editorial
16891 Running for Gold combinatorics graphs greedy probabilities sortings Statement B Codeforces Global Round 15 {1552} PROGRAMMING 500.0 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
762 Assiut Chess brute force interactive probabilities two pointers Statement E Codeforces Round 737 (Div. 2) {1557} PROGRAMMING 3000.0 Codeforces Round #737 Editorial
453 Tubular Bells interactive math number theory probabilities Statement F Codeforces Round 741 (Div. 2) {1562} PROGRAMMING 3500.0 Editorial of Codeforces Round 741 (Div. 2)
56 Laser Beams *special geometry probabilities Statement H Kotlin Heroes: Episode 8 {1571} PROGRAMMING Kotlin Heroes 8 Editorial
508 The Mind constructive algorithms interactive probabilities Statement M ICPC WF Moscow Invitational Contest - Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1578} PROGRAMMING Tutorial (PDF)
56 Game of Chance math probabilities Statement G ICPC WF Moscow Invitational Contest - Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1578} PROGRAMMING Tutorial (PDF)
403 The Sum of Good Numbers hashing probabilities Statement G 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
613 Party Organization probabilities Statement F Bubble Cup 14 - Finals Online Mirror (Unrated, ICPC Rules, Teams Preferred, Div. 2) {1600} PROGRAMMING BubbleCup2021.pdf
2805 Messages greedy math probabilities sortings Statement E Educational Codeforces Round 117 (Rated for Div. 2) {1612} PROGRAMMING 97164
1467 Robot Cleaner Revisit dp implementation math probabilities Statement D Codeforces Round 763 (Div. 2) {1623} PROGRAMMING 2500.0 Codeforces Round #763 (Div. 2) Editorial
552 Expected Components combinatorics number theory probabilities Statement E Codeforces Round 768 (Div. 1) {1630} PROGRAMMING 2500.0 Editorial of Codeforces Round #768
1497 Two Arrays bitmasks brute force combinatorics hashing probabilities two pointers Statement D Codeforces Round 773 (Div. 1) {1641} PROGRAMMING 1750.0 Codeforces Round #773 editorial
803 Centroid Probabilities combinatorics dp fft math Statement E Codeforces Round 783 (Div. 1) {1667} PROGRAMMING 2750.0 Codeforces Round #783 Editorial 3000
692 Mark and the Online Exam bitmasks constructive algorithms interactive math probabilities Statement F Codeforces Round 807 (Div. 2) {1705} PROGRAMMING 3000.0 Codeforces Round #807 (Div 2.) Editorial
6219 Tournament Countdown constructive algorithms fft greedy greedy interactive number theory probabilities Statement D Codeforces Round 812 (Div. 2) {1713} PROGRAMMING 2000.0 Codeforces Round #812 (Div. 2) Editorial 1800
4145 Edge Split brute force constructive algorithms dfs and similar graphs probabilities trees Statement D Codeforces Round 819 (Div. 1 + Div. 2) and Grimoire of Code Annual Contest 2022 {1726} PROGRAMMING 2000.0 Codeforces Round #819 (Div. 1 + Div. 2) and Grimoire of Code Annual Contest 2022 Editorial
7899 Guess the Cycle Size interactive probabilities Statement E Codeforces Round 820 (Div. 3) {1729} PROGRAMMING Codeforces Round #820 (Div. 3) Editorial
1074 Ela Goes Hiking dp probabilities Statement E Dytechlab Cup 2022 {1737} PROGRAMMING 2750.0 Editorial of Dytechlab Cup 2022
8350 Problem with Random Tests brute force hashing probabilities Statement D Educational Codeforces Round 137 (Rated for Div. 2) {1743} PROGRAMMING Educational Codeforces Round 137 Editorial 1700
2637 Kazaee data structures hashing probabilities Statement F Codeforces Global Round 23 {1746} PROGRAMMING 2500.0 Codeforces Global Round 23 Editorial
5255 Wish I Knew How to Sort dp math probabilities Statement C Codeforces Round 829 (Div. 1) {1753} PROGRAMMING 1750.0 Tutorial 2000
155 Centroid Guess interactive probabilities trees Statement G Pinely Round 1 (Div. 1 + Div. 2) {1761} PROGRAMMING 3500.0 Pinely Round 1 (Div. 1 + Div. 2) Editorial
758 Chemistry Lab dp geometry probabilities Statement F 2022-2023 ICPC, NERC, Southern and Volga Russian Regional Contest (Online Mirror, ICPC Rules, Preferably Teams) {1765} PROGRAMMING 109642 2200
551 Card Guessing dp probabilities Statement C 2022-2023 ICPC, NERC, Southern and Volga Russian Regional Contest (Online Mirror, ICPC Rules, Preferably Teams) {1765} PROGRAMMING 109642 2600
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
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
1899 Amazing Trick constructive algorithms probabilities Statement A 2022-2023 ICPC, NERC, Northern Eurasia Onsite (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1773} PROGRAMMING 1900
969 BinCoin divide and conquer hashing implementation probabilities trees Statement B 2022-2023 ICPC, NERC, Northern Eurasia Onsite (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1773} PROGRAMMING 2200
545 Game of Questions bitmasks dp math probabilities Statement G 2022-2023 ICPC, NERC, Northern Eurasia Onsite (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1773} PROGRAMMING 2800
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
461 Infinite Game combinatorics dp games probabilities Statement E VK Cup 2022 - Финальный раунд (Engine) {1784} PROGRAMMING 3000.0 Codeforces Round #850 Editorial
379 Roads in E City interactive math probabilities trees Statement E Codeforces Round 866 (Div. 1) {1819} PROGRAMMING 2750.0 Codeforces Round #866 (Div.1, Div.2, based on Lipetsk Team Olympiad) Editorial
1283 Random Walk dp graphs math probabilities trees Statement F Codeforces Round 868 (Div. 2) {1823} PROGRAMMING 2500.0 115465
5971 LuoTianyi and the Floating Islands (Easy Version) combinatorics math probabilities trees Statement B1 Codeforces Round 872 (Div. 1) {1824} PROGRAMMING 500.0 CodeForces Round 872(Div. 1&2) Editorial 1800
3340 LuoTianyi and the Floating Islands (Hard Version) combinatorics dfs and similar math probabilities trees Statement B2 Codeforces Round 872 (Div. 1) {1824} PROGRAMMING 750.0 CodeForces Round 872(Div. 1&2) Editorial 2300
456 Fading into Fog geometry interactive math probabilities Statement F Codeforces Round 870 (Div. 2) {1826} PROGRAMMING 3000.0 Codeforces Round #870 (Div. 2) Editorial 2800
1162 Twin Clusters bitmasks math meet-in-the-middle probabilities Statement C Codeforces Round 880 (Div. 1) {1835} PROGRAMMING 1500.0 Codeforces Round 880 Editorial
274 Old Mobile dp math probabilities Statement E Codeforces Round 880 (Div. 1) {1835} PROGRAMMING 2250.0 Codeforces Round 880 Editorial
2781 In Search of Truth (Easy Version) brute force constructive algorithms interactive math probabilities Statement G1 Codeforces Round 878 (Div. 3) {1840} PROGRAMMING Codeforces Round #878 (Div.3) Editorial
1180 In Search of Truth (Hard Version) constructive algorithms interactive math probabilities Statement G2 Codeforces Round 878 (Div. 3) {1840} PROGRAMMING Codeforces Round #878 (Div.3) Editorial
850 Tenzing and Random Real Numbers 2-sat bitmasks dp probabilities Statement H CodeTON Round 5 (Div. 1 + Div. 2, Rated, Prizes!) {1842} PROGRAMMING 3750.0 CodeTON Round 5 Editorial
1568 Tenzing and Random Operations combinatorics dp math probabilities Statement G CodeTON Round 5 (Div. 1 + Div. 2, Rated, Prizes!) {1842} PROGRAMMING 3000.0 CodeTON Round 5 Editorial
1777 Expected Destruction dp math probabilities Statement C Codeforces Round 889 (Div. 1) {1854} PROGRAMMING 1500.0 Editorial of Codeforces Round 889 (Div. 1 + Div. 2)
3035 Guess Game bitmasks combinatorics constructive algorithms data structures games math probabilities strings trees Statement E Harbour.Space Scholarship Contest 2023-2024 (Div. 1 + Div. 2) {1864} PROGRAMMING 2000.0 Harbour.Space Scholarship Contest 2023-2024 (Div. 1 + Div. 2) Editorial
492 Asterism Stream dp math matrices probabilities Statement H Harbour.Space Scholarship Contest 2023-2024 (Div. 1 + Div. 2) {1864} PROGRAMMING 3500.0 Harbour.Space Scholarship Contest 2023-2024 (Div. 1 + Div. 2) Editorial
967 Mighty Rock Tower combinatorics dp math probabilities Statement M COMPFEST 15 - Preliminary Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1866} PROGRAMMING COMPFEST 15 Preliminary — Editorial
2169 Jellyfish and EVA dp graphs greedy math probabilities Statement C Codeforces Round 901 (Div. 1) {1874} PROGRAMMING 1500.0 Codeforces Round 901 (Div. 1, Div. 2) Editorial
927 Jellyfish and Miku dp math probabilities Statement D Codeforces Round 901 (Div. 1) {1874} PROGRAMMING 2250.0 Codeforces Round 901 (Div. 1, Div. 2) Editorial
140 Fugitive Frenzy math probabilities Statement F 2023-2024 ICPC, NERC, Northern Eurasia Onsite (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1912} PROGRAMMING Tutorials (PDF) 3100
2053 ace5 and Task Order binary search divide and conquer implementation interactive probabilities sortings Statement E Codeforces Round 922 (Div. 2) {1918} PROGRAMMING 2500.0 Codeforces Round #922 (Div. 2) Editorial
533 Paper Cutting Again combinatorics probabilities Statement E Codeforces Round 921 (Div. 1) {1924} PROGRAMMING 2500.0 Codeforces Round 921 (Div. 1, Div. 2) Editorial
4756 Good Trip combinatorics dp math probabilities Statement D Codeforces Round 921 (Div. 2) {1925} PROGRAMMING 1750.0 Codeforces Round 921 (Div. 1, Div. 2) Editorial
1609 Rare Coins combinatorics math probabilities Statement F Educational Codeforces Round 163 (Rated for Div. 2) {1948} PROGRAMMING Educational Codeforces Round 163 Editorial
426 Clacking Balls combinatorics math probabilities Statement G Codeforces Global Round 25 {1951} PROGRAMMING 3250.0 Codeforces Global Round 25 Editorial
660 Frequency Mismatch (Easy Version) binary search data structures divide and conquer hashing probabilities trees Statement F1 Codeforces Round 940 (Div. 2) and CodeCraft-23 {1957} PROGRAMMING 2250.0 Codeforces Round #940 and CodeCraft-23 (Div. 2) Editorial 2600
605 Frequency Mismatch (Hard Version) binary search data structures dfs and similar hashing probabilities trees Statement F2 Codeforces Round 940 (Div. 2) and CodeCraft-23 {1957} PROGRAMMING 1250.0 Codeforces Round #940 and CodeCraft-23 (Div. 2) Editorial 2700
308 Arithmancy (Medium) constructive algorithms interactive probabilities strings Statement D2 Helvetic Coding Contest 2024 online mirror (teams allowed, unrated) {1970} PROGRAMMING Helvetic Coding Contest 2024 Editorial 2600
2460 I Love Balls combinatorics math probabilities Statement E Codeforces Round 956 (Div. 2) and ByteRace 2024 {1983} PROGRAMMING 2000.0
798 Turtle and Three Sequences data structures dp graphs greedy meet-in-the-middle probabilities two pointers Statement F Codeforces Round 968 (Div. 2) {2003} PROGRAMMING 2500.0 sol-zh.pdf
3963 Expected Power bitmasks brute force dp math number theory probabilities Statement E Codeforces Round 976 (Div. 2) and Divide By Zero 9.0 {2020} PROGRAMMING 2000.0 Tutorial for Codeforces Round 976 (Div. 2) and Divide By Zero 9.0
1892 Alice's Adventures in the Rabbit Hole constructive algorithms dfs and similar dp greedy math probabilities trees Statement E Codeforces Round 986 (Div. 2) {2028} PROGRAMMING 2000.0 Codeforces Round 986 (Div. 2) Editorial
2656 Control of Randomness combinatorics dfs and similar graphs greedy math probabilities trees Statement E Codeforces Round 992 (Div. 2) {2040} PROGRAMMING 2250.0 Codeforces Round #992 (Div.2) Editorial
993 Condorcet Elections constructive algorithms graphs probabilities Statement A European Championship 2025 - Online Mirror (Unrated, ICPC Rules, Teams Preferred) {2068} PROGRAMMING 140239
20785 Perfecto brute force constructive algorithms greedy math probabilities Statement B Codeforces Round 1007 (Div. 2) {2071} PROGRAMMING 1000.0 Codeforces Round 1007 (Div. 2) Editorial
794 LeaFall combinatorics probabilities trees Statement E Codeforces Round 1007 (Div. 2) {2071} PROGRAMMING 2500.0 Codeforces Round 1007 (Div. 2) Editorial
6623 Empty Triangle geometry interactive probabilities Statement E Codeforces Round 1009 (Div. 3) {2074} PROGRAMMING Codeforces Round 1009 (Div. 3) — Editorial
4053 Math Division bitmasks dp math probabilities Statement A Codeforces Round 1010 (Div. 1, Unrated) {2081} PROGRAMMING 500.0 Codeforces Round 1010 (Div. 1, Div. 2, based on Zhili Cup 2025) Editorial
1400 Key of Like (Easy Version) dp math probabilities Statement C1 Codeforces Round 1012 (Div. 1) {2089} PROGRAMMING 1000.0 Codeforces Round 1012 (Div.1, Div. 2, based on THUPC 2025 — Finals) Editorial
254 Key of Like (Hard Version) dp math probabilities Statement C2 Codeforces Round 1012 (Div. 1) {2089} PROGRAMMING 1250.0 Codeforces Round 1012 (Div.1, Div. 2, based on THUPC 2025 — Finals) Editorial