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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
928 Tickets combinatorics math probabilities Statement D Codeforces Beta Round 26 (Codeforces format) {26} PROGRAMMING Разбор Codeforces Beta Round #26 (ещё один) 2800
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
558 Help Shrek and Donkey dp games math probabilities Statement E Codeforces Beta Round 78 (Div. 1 Only) {98} PROGRAMMING Editorial 2500
4243 Basketball Team combinatorics dp math probabilities Statement B Codeforces Beta Round 83 (Div. 1 Only) {107} PROGRAMMING Tutorial 1700
811 Museum math matrices probabilities Statement D Codeforces Beta Round 86 (Div. 1 Only) {113} PROGRAMMING Codeforces Beta Round #86 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
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
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
2500 Ghd brute force math probabilities Statement D Codeforces Round 213 (Div. 1) {364} PROGRAMMING Codeforces Round #213 Editorial 2600
927 Square Table constructive algorithms math probabilities Statement E RCC 2014 Warmup (Div. 2) {417} PROGRAMMING RCC 2014 WarmUp Analysis 2400
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
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
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
36817 Dreamoon and WiFi bitmasks brute force combinatorics dp math probabilities Statement B Codeforces Round 272 (Div. 2) {476} PROGRAMMING 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
620 Kyoya and Train dp fft graphs math probabilities Statement E Codeforces Round 309 (Div. 1) {553} PROGRAMMING Codeforces Round #309 Editorial 3300
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
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
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
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
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
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
2641 Random Query data structures math probabilities two pointers Statement F Educational Codeforces Round 28 {846} PROGRAMMING 54357 2000
2600 New Year and Arbitrary Arrangement dp math probabilities Statement D Good Bye 2017 {908} PROGRAMMING Good Bye 2017 Editorial 2200
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
2805 Fafa and Ancient Alphabet math probabilities Statement D Codeforces Round 465 (Div. 2) {935} PROGRAMMING 1900
3317 Intercity Travelling combinatorics math probabilities Statement E Educational Codeforces Round 47 (Rated for Div. 2) {1009} PROGRAMMING 60630 1900
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
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
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
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
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
211 Alice and the Cactus dfs and similar graphs math probabilities Statement F Codeforces Round 593 (Div. 2) {1236} PROGRAMMING 70654 2900
1524 Tree Queries data structures probabilities trees Statement D Codeforces Round 601 (Div. 1) {1254} PROGRAMMING Codeforces Round #601 Editorial 2600
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
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
1046 Slime and Biscuits math probabilities Statement D Codeforces Round 641 (Div. 1) {1349} PROGRAMMING 2000.0 Codeforces Round #641 Editorial 3200
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
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
163 Nezzar and Chocolate Bars combinatorics fft math probabilities Statement F Codeforces Round 698 (Div. 1) {1477} PROGRAMMING 4000.0 87294 3500
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
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
2365 Assimilation IV combinatorics dp math probabilities Statement E Educational Codeforces Round 109 (Rated for Div. 2) {1525} PROGRAMMING 90793
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
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
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 Game of Chance math probabilities Statement G ICPC WF Moscow Invitational Contest - Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1578} PROGRAMMING Tutorial (PDF)
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
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
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
5255 Wish I Knew How to Sort dp math probabilities Statement C Codeforces Round 829 (Div. 1) {1753} PROGRAMMING 1750.0 Tutorial 2000
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
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
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
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
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
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
2460 I Love Balls combinatorics math probabilities Statement E Codeforces Round 956 (Div. 2) and ByteRace 2024 {1983} PROGRAMMING 2000.0
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
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
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
903 Gellyfish and Eternal Violet combinatorics dp greedy math meet-in-the-middle probabilities Statement C Codeforces Round 1028 (Div. 1) {2115} PROGRAMMING 1750.0 Codeforces Round 1028 (Div.1, Div.2) Editorial
104 Inter Active (Hard Version) binary search bitmasks constructive algorithms graphs implementation interactive math probabilities Statement G2 Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) {2127} PROGRAMMING 2750.0 Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) Editorial
592 Hidden Single (Version 2) divide and conquer interactive math probabilities Statement E2 Codeforces Round 1053 (Div. 1) {2150} PROGRAMMING 1750.0 Editorial of Codeforces Round 1053 (Div. 1, Div. 2)
1012 Hidden Single (Version 1) divide and conquer interactive math probabilities sortings Statement E1 Codeforces Round 1053 (Div. 1) {2150} PROGRAMMING 2000.0 Editorial of Codeforces Round 1053 (Div. 1, Div. 2)
402 Isaac's Queries brute force constructive algorithms dfs and similar divide and conquer greedy interactive math probabilities Statement G Codeforces Round 1066 (Div. 1 + Div. 2) {2157} PROGRAMMING 3000.0 Codeforces Round 1066 (Div. 1 + Div. 2) Editorial
2251 Removal of a Sequence (Hard Version) binary search constructive algorithms divide and conquer greedy implementation math number theory probabilities Statement D2 Educational Codeforces Round 184 (Rated for Div. 2) {2169} PROGRAMMING Educational Codeforces Round 184 Editorial
1136 Beautiful Patterns (Easy Version) math probabilities Statement C1 Codeforces Round 1069 (Div. 1) {2174} PROGRAMMING 1500.0 Codeforces Round 1069 Editorial
990 Beautiful Patterns (Hard Version) math probabilities Statement C2 Codeforces Round 1069 (Div. 1) {2174} PROGRAMMING 500.0 Codeforces Round 1069 Editorial
697 Jinx or Jackpot brute force dp math probabilities Statement J 2025-2026 ICPC, NERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {2181} PROGRAMMING Tutorial
165 Fish Fight dp math probabilities Statement F Codeforces Round 1081 (Div. 2) {2192} PROGRAMMING 3000.0 Codeforces Round 1081 (Div. 2) Editorial
970 Operation Permutation combinatorics dp math probabilities Statement G Codeforces Round 1084 (Div. 3) {2200} PROGRAMMING Codeforces Round 1084 (Div. 3) Editorial
589 Interval Game bitmasks combinatorics dp games greedy math probabilities Statement F Codeforces Round 1091 (Div. 2) and CodeCraft 26 {2217} PROGRAMMING 2750.0