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825 Maze dfs and similar dp probabilities trees Statement E Codeforces Beta Round 92 (Div. 1 Only) {123} PROGRAMMING Codeforces Beta Round #92 - Analysis 2600
14061 Students and Shoelaces brute force dfs and similar graphs implementation Statement B Codeforces Beta Round 94 (Div. 2 Only) {129} PROGRAMMING Problem D of Beta Round 94 1200
5324 Subway dfs and similar graphs Statement D Codeforces Beta Round 95 (Div. 2) {131} PROGRAMMING Some ideas for Round #95 (Div 2) 1600
2536 Pairs of Numbers brute force dfs and similar math number theory Statement B Codeforces Testing Round 3 {134} PROGRAMMING 1800
5483 Quantity of Strings combinatorics dfs and similar graphs math Statement B Codeforces Round 107 (Div. 1) {150} PROGRAMMING Tutorial 1800
702 Wizards and Bets dfs and similar graphs math matrices Statement E Codeforces Round 114 (Div. 1) {167} PROGRAMMING Codeforces Round #114 — Tutorial 2900
282 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
1761 Dima and Trap Graph binary search data structures dfs and similar dsu shortest paths two pointers Statement D Codeforces Round 214 (Div. 2) {366} PROGRAMMING Codeforces Round #214 (Div. 2) — Tutorial 2400
7402 Gargari and Permutations dfs and similar dp graphs implementation Statement D Codeforces Round 264 (Div. 2) {463} PROGRAMMING CF 264 Div 2 Tutorial 2000
1769 Caisa and Tree brute force dfs and similar math number theory trees Statement E Codeforces Round 264 (Div. 2) {463} PROGRAMMING CF 264 Div 2 Tutorial 2400
4425 Valid Sets dfs and similar dp math trees Statement D Codeforces Round 277 (Div. 2) {486} PROGRAMMING Codeforces Round #277(Div. 2) Editorial 2300
2332 Chocolate brute force dfs and similar math meet-in-the-middle number theory Statement D Codeforces Round 279 (Div. 2) {490} PROGRAMMING Codeforces Round #279 (Div. 2) Editorial 1900
9689 New Year Permutation dfs and similar dsu graphs greedy math sortings Statement B Good Bye 2014 {500} PROGRAMMING Tutorial 2 1600
64304 Two Buttons dfs and similar graphs greedy implementation math shortest paths Statement B Codeforces Round 295 (Div. 2) {520} PROGRAMMING Codeforces Round #295 Editorial (now with bonuses!) 1400
1666 Demiurges Play Again dfs and similar dp math trees Statement E Codeforces Round 300 {538} PROGRAMMING Codeforces Round #300 Editorial (+challenges) 2200
541 Superhero's Job dfs and similar dp hashing math number theory Statement D VK Cup 2015 - Round 3 (unofficial online mirror, Div. 1 only) {542} PROGRAMMING 17697 2600
2422 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
1452 Happy Tree Party data structures dfs and similar graphs math trees Statement D Codeforces Round 329 (Div. 2) {593} PROGRAMMING 2300
2718 Moodular Arithmetic combinatorics dfs and similar dsu math number theory Statement B Codeforces Round 334 (Div. 1) {603} PROGRAMMING Codeforces Round #334 Editorial 2000
2059 Square Root of Permutation combinatorics constructive algorithms dfs and similar graphs math Statement E Educational Codeforces Round 4 {612} PROGRAMMING 22299 2200
915 Yash And Trees bitmasks data structures dfs and similar math number theory Statement G Manthan, Codefest 16 {633} PROGRAMMING Manthan, Codefest 16: Editorials 2700
365 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
6660 Swaps in Permutation dfs and similar dsu math Statement D Educational Codeforces Round 14 {691} PROGRAMMING Editorial of Educational Codeforces Round 14 1700
3848 Puzzles dfs and similar math probabilities trees Statement B Codeforces Round 362 (Div. 1) {696} PROGRAMMING Codeforces Round #362 (Editorial) 1800
5078 Directed Roads combinatorics dfs and similar graphs math Statement D Codeforces Round 369 (Div. 2) {711} PROGRAMMING 46830 1900
18517 Transformation: from A to B brute force dfs and similar math Statement A Technocup 2017 - Elimination Round 1 (Unofficially Open for Everyone, Rated for Div. 2) {727} PROGRAMMING Tutorial 1100
5714 Arpa's loud Owf and Mehrdad's evil plan dfs and similar math Statement A Codeforces Round 383 (Div. 1) {741} PROGRAMMING Codeforces Round #383 editorial 1600
3574 Mahmoud and a xor trip bitmasks constructive algorithms data structures dfs and similar dp math trees Statement E Codeforces Round 396 (Div. 2) {766} PROGRAMMING Codeforces round #396 editorial 2200
400 Send the Fool Further! (hard) dfs and similar dp math trees Statement J3 Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} PROGRAMMING helvetic-coding-contest-2017-editorial.pdf 2400
364 Send the Fool Further! (hard) dfs and similar dp math trees Statement L Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} PROGRAMMING helvetic-coding-contest-2017-editorial.pdf 2800
3803 Ilya And The Tree dfs and similar graphs math number theory trees Statement C Codeforces Round 430 (Div. 2) {842} PROGRAMMING Tutorial Codeforces Round #430 (Div. 2) 2000
6001 Sorting by Subsequences dfs and similar dsu implementation math sortings Statement A AIM Tech Round 4 (Div. 1) {843} PROGRAMMING AIM Tech Round 4 -- Editorial 1400
416 Upgrading Tree constructive algorithms dfs and similar graphs math trees Statement C AIM Tech Round 4 (Div. 1) {843} PROGRAMMING AIM Tech Round 4 -- Editorial 2900
2223 Shortest Path Problem? dfs and similar graphs math Statement G Educational Codeforces Round 27 {845} PROGRAMMING 53986 2400
5196 Bertown Subway dfs and similar greedy math Statement C Educational Codeforces Round 31 {884} PROGRAMMING 55470 1500
2114 Prime Gift binary search dfs and similar math meet-in-the-middle number theory two pointers Statement E Codeforces Round 456 (Div. 2) {912} PROGRAMMING Codeforces Round #456 (Div. 2) Editorial 2600
10080 Swap Adjacent Elements dfs and similar greedy math sortings two pointers Statement C Educational Codeforces Round 37 (Rated for Div. 2) {920} PROGRAMMING T 1500
997 Fafa and Ancient Mathematics dfs and similar dp trees Statement E Codeforces Round 465 (Div. 2) {935} PROGRAMMING editorial 2500
20863 Divide by three, multiply by two dfs and similar math sortings Statement D Codeforces Round 479 (Div. 3) {977} PROGRAMMING Codeforces Round #479 (Div. 3) Editorial 1400
1140 Maximum Matching bitmasks brute force dfs and similar dp graphs Statement E Codeforces Round 508 (Div. 2) {1038} PROGRAMMING Tutorial 2400
1522 Network Safety dfs and similar dsu graphs math sortings Statement C Codeforces Round 507 (Div. 1, based on Olympiad of Metropolises) {1039} PROGRAMMING 61668 2300
4183 Fun with Integers dfs and similar graphs implementation math Statement D Codeforces Round 520 (Div. 2) {1062} PROGRAMMING Tutorial 1800
991 Johnny Solving constructive algorithms dfs and similar graphs math Statement C Codeforces Round 534 (Div. 1) {1103} PROGRAMMING Codeforces Round #534 — Editorial 2800
17308 Edgy Trees dfs and similar dsu graphs math trees Statement C Codeforces Round 548 (Div. 2) {1139} PROGRAMMING Codeforces Round #548 Editorial 1500
3935 Lynyrd Skynyrd data structures dfs and similar dp math trees Statement B Codeforces Round 549 (Div. 1) {1142} PROGRAMMING Codeforces Round #549 Editorial 2300
1226 Frog Jumping dfs and similar math number theory Statement D Forethought Future Cup - Elimination Round {1146} PROGRAMMING 66639 2100
9401 Neko Performs Cat Furrier Transform bitmasks constructive algorithms dfs and similar math Statement B Codeforces Round 554 (Div. 2) {1152} PROGRAMMING T 1300
5619 Serval and Rooted Tree binary search dfs and similar dp greedy trees Statement D Codeforces Round 551 (Div. 2) {1153} PROGRAMMING Editorial 1800
2314 Permutation recovery constructive algorithms data structures dfs and similar graphs greedy math sortings Statement C Codeforces Round 559 (Div. 1) {1158} PROGRAMMING 66993 2300
1181 Graph Traveler brute force data structures dfs and similar dp graphs implementation math number theory Statement F Codeforces Round 578 (Div. 2) {1200} PROGRAMMING Codeforces Round #578 (Div. 2) Editorial 2500
271 Alice and the Cactus dfs and similar graphs math probabilities Statement F Codeforces Round 593 (Div. 2) {1236} PROGRAMMING 70654 2900
9557 0-1 MST dfs and similar dsu graphs sortings Statement B Codeforces Round 599 (Div. 1) {1242} PROGRAMMING Codeforces Round #599 Editorial 1900
18584 Books Exchange (hard version) dfs and similar dsu math Statement B2 Codeforces Round 595 (Div. 3) {1249} PROGRAMMING Codeforces Round #595 (Div. 3) Editorial 1300
3040 Subset with Zero Sum constructive algorithms dfs and similar graphs math Statement G Good Bye 2019 {1270} PROGRAMMING Разбор Goodbye 2019 2700
626 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
3579 Infinite Path brute force dfs and similar graphs math number theory Statement D Educational Codeforces Round 84 (Rated for Div. 2) {1327} PROGRAMMING Educational Codeforces Round 84 Editorial 2200
2005 Quantifier Question dfs and similar dp graphs math Statement C Codeforces Round 639 (Div. 1) {1344} PROGRAMMING 1500.0 Codeforces Round #639 Editorial 2600
19712 Binary String Reconstruction constructive algorithms dfs and similar math Statement F Codeforces Round 640 (Div. 4) {1352} PROGRAMMING 77161 1500
952 Graph *special dfs and similar dp math Statement A Baltic Olympiad in Informatics 2020, Day 2 (IOI, Unofficial Mirror Contest, Unrated) {1387} PROGRAMMING T
10475 Uncle Bogdan and Country Happiness dfs and similar dp greedy math trees Statement C Codeforces Round 660 (Div. 2) {1388} PROGRAMMING 1500.0 Codeforces Round #660 Editorial 1800
712 Omkar and Pies bitmasks dfs and similar dp math Statement G Codeforces Global Round 10 {1392} PROGRAMMING 3000.0 Codeforces Global Round 10 — Editorial
10721 Maximum Distributed Tree constructive algorithms dfs and similar greedy math number theory sortings trees Statement D Codeforces Round 665 (Div. 2) {1401} PROGRAMMING 1750.0 Codeforces Round #665 (Div. 2) Editorial
1302 Game of Pairs constructive algorithms dfs and similar interactive math number theory Statement D Codeforces Round 668 (Div. 1) {1404} PROGRAMMING 2250.0 Codeforces Round #668 Editorial
3079 Euclid's nightmare dfs and similar dsu graphs math Statement F Good Bye 2020 {1466} PROGRAMMING 1750.0 Good Bye 2020 Editorial
28133 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
7994 Strange Beauty dfs and similar dp math number theory Statement G Codeforces Round 697 (Div. 3) {1475} PROGRAMMING Codeforces Round #697 (Div. 3) Editorial
15541 Minimum Ties brute force constructive algorithms dfs and similar graphs greedy implementation math Statement C Educational Codeforces Round 104 (Rated for Div. 2) {1487} PROGRAMMING 87873
1582 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
1088 Christmas Game data structures dfs and similar dp games math trees Statement F CodeCraft-21 and Codeforces Round 711 (Div. 2) {1498} PROGRAMMING 3000.0 CodeCraft-21 and Codeforces Round #711 (Div. 2) Editorial
1770 Complete the MST data structures dfs and similar dsu graphs greedy math Statement C Codeforces Round 715 (Div. 1) {1508} PROGRAMMING 1500.0 Codeforces Round #715 Editorial
1397 Phoenix and Odometers dfs and similar graphs math number theory Statement G Codeforces Global Round 14 {1515} PROGRAMMING 3500.0 Editorial
2332 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
13979 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
2846 Figure Fixing constructive algorithms dfs and similar dsu graphs math Statement F Codeforces Round 726 (Div. 2) {1537} PROGRAMMING 2000.0 Codeforces Round #726 (Div.2) Editorial
5654 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
153 Organizing a Music Festival dfs and similar math Statement I Codeforces Global Round 15 {1552} PROGRAMMING 3750.0 Editorial of Global Round 15
3830 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
1426 You dfs and similar dp math number theory Statement E Codeforces Round 735 (Div. 2) {1554} PROGRAMMING 3000.0 Editorial of Codeforces Round #735 (Div. 2) 2600
2653 Hemose in ICPC ? binary search dfs and similar divide and conquer interactive math number theory trees Statement D Codeforces Round 746 (Div. 2) {1592} PROGRAMMING 2000.0 95583
1059 Christmas Chocolates dfs and similar dp games graphs implementation math number theory shortest paths trees Statement E Codeforces Round 761 (Div. 2) {1617} PROGRAMMING 3000.0 Editorial for Codeforces Round #761 (Div. 2)
7558 Hidden Permutations dfs and similar interactive math Statement C Hello 2022 {1621} PROGRAMMING 1500.0
657 Sum of Matchings dfs and similar greedy implementation math Statement E Educational Codeforces Round 124 (Rated for Div. 2) {1651} PROGRAMMING Educational Codeforces Round 124 Editorial
3092 Potion Brewing Class dfs and similar implementation math number theory trees Statement D Codeforces Round 778 (Div. 1 + Div. 2, based on Technocup 2022 Final Round) {1654} PROGRAMMING 2000.0 Editorial of Codeforces Round #778 (Div. 1 + Div. 2, based on Technocup 2022 Final Round) 2100
2011 AND-MEX Walk bitmasks brute force data structures dfs and similar dsu graphs greedy Statement E Codeforces Round 782 (Div. 2) {1659} PROGRAMMING 2250.0 Codeforces Round #782 (Div. 2) Editorial
11119 Where is the Pizza? data structures dfs and similar dsu graphs implementation math Statement C Codeforces Round 788 (Div. 2) {1670} PROGRAMMING 1750.0 Tutorial 1400
2954 Remove Directed Edges dfs and similar dp graphs Statement G Codeforces Round 786 (Div. 3) {1674} PROGRAMMING 102482
777 Unordered Swaps constructive algorithms dfs and similar graphs greedy math sortings Statement E Codeforces Round 793 (Div. 2) {1682} PROGRAMMING 2500.0 Codeforces Round #793 (Div. 2) Editorial
1168 K-Set Tree combinatorics dfs and similar dp math trees Statement F CodeCraft-22 and Codeforces Round 795 (Div. 2) {1691} PROGRAMMING 2750.0 Editorial for CodeCraft-22 and Codeforces Round #795 (Div. 2)
31742 Three Doors brute force dfs and similar math Statement A Educational Codeforces Round 132 (Rated for Div. 2) {1709} PROGRAMMING 105164
10640 SlavicG's Favorite Problem bitmasks brute force constructive algorithms data structures dfs and similar graphs greedy Statement G Codeforces Round 835 (Div. 4) {1760} PROGRAMMING 109348
1238 Doremy's Experimental Tree brute force constructive algorithms dfs and similar dsu sortings trees Statement F Codeforces Global Round 24 {1764} PROGRAMMING 2250.0 Codeforces Global Round 24 Editorial
8855 Friendly Spiders dfs and similar graphs math number theory shortest paths Statement D Codeforces Round 843 (Div. 2) {1775} PROGRAMMING 2000.0 Codeforces Round #843 (Div. 2) Editorial
1160 The Tree Has Fallen! bitmasks dfs and similar math trees Statement E Codeforces Round 848 (Div. 2) {1778} PROGRAMMING 2250.0 Codeforces Round #848 (Div. 2) Editorial
955 Maximizing Root dfs and similar dp graphs math trees Statement F Codeforces Round 848 (Div. 2) {1778} PROGRAMMING 2750.0 Codeforces Round #848 (Div. 2) Editorial
4129 Timofey and Black-White Tree brute force dfs and similar divide and conquer graphs greedy math shortest paths trees Statement F Codeforces Round 847 (Div. 3) {1790} PROGRAMMING 111948
1948 There Should Be a Lot of Maximums data structures dfs and similar dsu graphs trees Statement E Codeforces Round 862 (Div. 2) {1805} PROGRAMMING 2250.0 Editorial of Codeforces Round #862 (Div. 2)
3532 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
22242 Forever Winter dfs and similar graphs math Statement F Codeforces Round 871 (Div. 4) {1829} PROGRAMMING Codeforces Round 871 (Div. 4) Editorial 1300
688 Doctor's Brown Hypothesis dfs and similar graphs math number theory Statement D Codeforces Round 880 (Div. 1) {1835} PROGRAMMING 1750.0 Codeforces Round 880 Editorial
2209 Omsk Metro (hard version) data structures dfs and similar divide and conquer dp implementation math trees Statement F2 Codeforces Round 881 (Div. 3) {1843} PROGRAMMING Codeforces Round #881 (Div. 3) Editorial
6458 Omsk Metro (simple version) data structures dfs and similar dp greedy math trees Statement F1 Codeforces Round 881 (Div. 3) {1843} PROGRAMMING Codeforces Round #881 (Div. 3) Editorial
1202 Tree Weights bitmasks constructive algorithms data structures dfs and similar math matrices number theory trees Statement G Codeforces Round 884 (Div. 1 + Div. 2) {1844} PROGRAMMING 3500.0 Codeforces Round #884 (Div. 1 + Div. 2) Editorial
2189 Great Grids constructive algorithms dfs and similar dsu graphs math Statement E Codeforces Round 884 (Div. 1 + Div. 2) {1844} PROGRAMMING 2000.0 Codeforces Round #884 (Div. 1 + Div. 2) Editorial
1102 The Boss's Identity binary search bitmasks data structures dfs and similar greedy math sortings Statement F Codeforces Round 882 (Div. 2) {1847} PROGRAMMING 3000.0 Tutorial
7647 Selling a Menagerie dfs and similar dsu graphs implementation math Statement F Codeforces Round 895 (Div. 3) {1872} PROGRAMMING Codeforces Round 895 (Div. 3) Editorial
1494 wxhtzdy ORO Tree binary search bitmasks data structures dfs and similar math trees Statement G Codeforces Round 900 (Div. 3) {1878} PROGRAMMING Codeforces round #900 (Div.3) Editorial
1902 Infinite Card Game brute force dfs and similar games graphs greedy sortings Statement E Educational Codeforces Round 157 (Rated for Div. 2) {1895} PROGRAMMING Educational Codeforces Round 157 Editorial
4089 Unusual Entertainment data structures dfs and similar dsu shortest paths sortings trees Statement G Codeforces Round 909 (Div. 3) {1899} PROGRAMMING Разбор Codeforces Round 909 (Div. 3)
1525 Trees and XOR Queries Again bitmasks data structures dfs and similar implementation math trees Statement F Educational Codeforces Round 159 (Rated for Div. 2) {1902} PROGRAMMING Educational Codeforces Round 159 Editorial
2460 Light Bulbs (Easy Version) brute force combinatorics dfs and similar dp dsu graphs math Statement G1 Codeforces Round 916 (Div. 3) {1914} PROGRAMMING Codeforces Round 916 (Div. 3) Editorial
743 Group Division constructive algorithms dfs and similar graphs Statement F Good Bye 2023 {1916} PROGRAMMING 2750.0
5885 Sasha and a Walk in the City combinatorics dfs and similar dp math trees Statement D Codeforces Round 926 (Div. 2) {1929} PROGRAMMING 2000.0 Codeforces Round #926 (Div. 2) Editorial.
2344 Sasha and the Wedding Binary Search Tree combinatorics dfs and similar math sortings trees Statement F Codeforces Round 926 (Div. 2) {1929} PROGRAMMING 3000.0 Codeforces Round #926 (Div. 2) Editorial.
6040 GCD on a grid brute force dfs and similar dp math number theory Statement G Codeforces Round 938 (Div. 3) {1955} PROGRAMMING 128243
17630 Permutation Game brute force dfs and similar games graphs greedy math Statement D Codeforces Round 943 (Div. 3) {1968} PROGRAMMING 129096 1300
12707 Circle Perimeter binary search brute force dfs and similar geometry implementation math Statement F Codeforces Round 944 (Div. 4) {1971} PROGRAMMING Codeforces Round 944 (Div. 4) Editorial 1600
2851 ±1 2-sat dfs and similar graphs Statement H Codeforces Round 944 (Div. 4) {1971} PROGRAMMING Codeforces Round 944 (Div. 4) Editorial 2100
2931 Chain Queries binary search data structures dfs and similar implementation trees Statement E Codeforces Round 947 (Div. 1 + Div. 2) {1975} PROGRAMMING 2000.0 editorial_zh.pdf 2100
1075 Set bitmasks brute force combinatorics dfs and similar divide and conquer dp math Statement F Codeforces Round 947 (Div. 1 + Div. 2) {1975} PROGRAMMING 2500.0 editorial_zh.pdf 2600
1338 Splittable Permutations combinatorics data structures dfs and similar greedy math trees Statement E Educational Codeforces Round 166 (Rated for Div. 2) {1976} PROGRAMMING Educational Codeforces Round 166 Editorial
2208 Turtle and Multiplication constructive algorithms dfs and similar graphs number theory Statement D Codeforces Round 949 (Div. 2) {1981} PROGRAMMING 2000.0 Simplified Chinese Tutorial
1016 Court Blue (Easy Version) brute force dfs and similar dp math number theory Statement F1 EPIC Institute of Technology Round August 2024 (Div. 1 + Div. 2) {2002} PROGRAMMING 2000.0 EPIC Institute of Technology Round August 2024 (Div. 1 + Div. 2) Editorial
4427 Iris and the Tree brute force data structures dfs and similar dsu math trees Statement B Codeforces Round 969 (Div. 1) {2006} PROGRAMMING 1250.0 Tutorial
7562 Connect the Dots brute force dfs and similar dp dsu graphs math trees Statement D Codeforces Round 976 (Div. 2) and Divide By Zero 9.0 {2020} PROGRAMMING 1500.0 Tutorial for Codeforces Round 976 (Div. 2) and Divide By Zero 9.0
1399 C+K+S brute force constructive algorithms dfs and similar graphs greedy hashing math strings Statement C Codeforces Round 980 (Div. 1) {2023} PROGRAMMING 1500.0 135341
1977 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
14460 Sakurako, Kosuke, and the Permutation brute force data structures dfs and similar dsu fft greedy math Statement E Codeforces Round 981 (Div. 3) {2033} PROGRAMMING 135520
2748 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
18164 Find the Permutation dfs and similar graphs implementation sortings Statement B Codeforces Round 997 (Div. 2) {2056} PROGRAMMING 1250.0 Codeforces Round #997 (Div. 2) Editorial
1574 Counting Is Not Fun (Easy Version) combinatorics data structures dfs and similar dsu implementation math Statement F1 Codeforces Round 1000 (Div. 2) {2063} PROGRAMMING 1750.0 Codeforces Round 1000 (Div. 2) — Editorial
943 Counting Is Not Fun (Hard Version) combinatorics data structures dfs and similar dsu trees Statement F2 Codeforces Round 1000 (Div. 2) {2063} PROGRAMMING 1500.0 Codeforces Round 1000 (Div. 2) — Editorial
1692 Zebra-like Numbers bitmasks brute force dfs and similar dp math Statement E Educational Codeforces Round 177 (Rated for Div. 2) {2086} PROGRAMMING Educational Codeforces Round 177 Editorial
742 Numbers and Strings brute force dfs and similar dp implementation math Statement F Educational Codeforces Round 178 (Rated for Div. 2) {2104} PROGRAMMING Educational Codeforces Round 178 Editorial
284 Penguin Steps binary search dfs and similar flows graphs shortest paths Statement F Codeforces Round 1025 (Div. 2) {2109} PROGRAMMING 3000.0 Codeforces Round 1025 (Div. 2) Editorial
985 Two Arrays constructive algorithms dfs and similar graphs math Statement F Codeforces Round 1031 (Div. 2) {2113} PROGRAMMING 3000.0 Codeforces Round #1031 Editorial
5611 Small Operations binary search bitmasks brute force dfs and similar dp math number theory sortings Statement F Codeforces Round 1027 (Div. 3) {2114} PROGRAMMING 143268
2562 Red Light, Green Light (Hard version) binary search dfs and similar dp dsu graphs implementation number theory Statement D2 Codeforces Round 1030 (Div. 2) {2118} PROGRAMMING 1000.0 Codeforces Round 1030 (Div. 2) Editorial
8617 Red Light, Green Light (Easy version) brute force dfs and similar dp graphs implementation Statement D1 Codeforces Round 1030 (Div. 2) {2118} PROGRAMMING 1250.0 Codeforces Round 1030 (Div. 2) Editorial
7012 Inversion Value of a Permutation constructive algorithms dfs and similar dp math Statement D Educational Codeforces Round 183 (Rated for Div. 2) {2145} PROGRAMMING Educational Codeforces Round 183 Editorial
558 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
1027 Chain Prefix Rank (Easy Version) combinatorics dfs and similar dp math Statement F1 Codeforces Global Round 30 (Div. 1 + Div. 2) {2164} PROGRAMMING 2500.0 Codeforces Global Round 30 Editorial
4503 The 67th Iteration of "Counting is Fun" dfs and similar implementation math Statement G Codeforces Round 1090 (Div. 4) {2218} PROGRAMMING Codeforces Round 1090 (Div. 4) Editorial
907 Zhily and Signpost binary search chinese remainder theorem dfs and similar math number theory trees Statement C Codeforces Round 1097 (Div. 1, Based on Zhili Cup 2026) {2223} PROGRAMMING 1500.0 Codeforces Round 1097 (Div. 1, Div2, Based on Zhili Cup 2026) Tutorial