Codeforces problemset search & solutions
Exclude tags.

Review the problem statement from Codeforces (link will open a new tab). When you've matched your problem, go to the solutions.

Search on plain tags, ratings, names, and problem text. Example: brute force or binary search

Solved
Name
Tags
Solutions
Index
Contest
Type
Points
Tutorial
Rating Level
5873 Tournament bitmasks brute force dfs and similar greedy Statement B Codeforces Beta Round 27 (Codeforces format, Div. 2) {27} PROGRAMMING Codeforces Beta #27 - Tutorial 2000
19686 LLPS binary search bitmasks brute force greedy implementation strings Statement A Codeforces Round 127 (Div. 2) {202} PROGRAMMING 900
16293 Little Girl and Maximum XOR bitmasks dp greedy implementation math Statement D Codeforces Round 169 (Div. 2) {276} PROGRAMMING Codeforces Round #169 — Unofficial Editorial 1800
1492 Memory for Arrays binary search bitmasks greedy Statement C Croc Champ 2013 - Finals (online version, Div. 1) {309} PROGRAMMING Чемпионат КРОК 2013 — Финальный раунд — Разбор 1900
1088 Bags and Coins bitmasks constructive algorithms dp greedy Statement D Codeforces Round 207 (Div. 1) {356} PROGRAMMING 9210 2500
2905 Cunning Gena bitmasks dp greedy sortings Statement D RCC 2014 Warmup (Div. 2) {417} PROGRAMMING 2000
1408 Sereja and Table bitmasks greedy Statement B Codeforces Round 243 (Div. 1) {425} PROGRAMMING Codeforces Round #243 tutorial 2400
1029 Guess the Tree bitmasks constructive algorithms dp greedy trees Statement C Codeforces Round 245 (Div. 1) {429} PROGRAMMING Codeforces Round #245 — Editorial 2400
10426 The Child and Set bitmasks greedy implementation sortings Statement B Codeforces Round 250 (Div. 2) {437} PROGRAMMING 12513 1500
1850 PolandBall and Gifts bitmasks dp greedy Statement F 8VC Venture Cup 2017 - Elimination Round {755} PROGRAMMING 8VC Venture Cup 2017 — Elimination Round [Editorial] 2600
204 Sequence Recovery bitmasks data structures greedy Statement F Codeforces Round 408 (Div. 2) {796} PROGRAMMING Tutorial 2800
8454 Party Lemonade bitmasks dp greedy Statement C Hello 2018 {913} PROGRAMMING Tutorial 1600
2006 Jamie and Binary Sequence (changed after round) bitmasks greedy math Statement B Codeforces Round 457 (Div. 2) {916} PROGRAMMING Codeforces Round #457 (Div. 2) Editorial 1700
612 Erasing Substrings bitmasks dp greedy Statement F Educational Codeforces Round 38 (Rated for Div. 2) {938} PROGRAMMING Educational Codeforces Round 38 — Editorial 2600
4098 Subsequence Counting bitmasks constructive algorithms greedy implementation Statement C 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 1700
2171 Kuro and GCD and XOR and SUM binary search bitmasks brute force data structures dp dsu greedy math number theory strings trees Statement D Codeforces Round 482 (Div. 2) {979} PROGRAMMING 1750.0 Codeforces Round #482 (Div. 2) Editorial 2200
3544 Bookshelves bitmasks dp greedy Statement D Avito Code Challenge 2018 {981} PROGRAMMING Avito Code Challenge 2018 — разбор 1800
1049 Allowed Letters bitmasks flows graph matchings graphs greedy Statement G Educational Codeforces Round 47 (Rated for Div. 2) {1009} PROGRAMMING 60630 2500
19536 Powers Of Two bitmasks greedy Statement C Codeforces Round 529 (Div. 3) {1095} PROGRAMMING Codeforces Round #529 (Div. 3) Editorial 1400
10703 You Are Given Two Binary Strings... bitmasks greedy Statement A Educational Codeforces Round 70 (Rated for Div. 2) {1202} PROGRAMMING 68972 1100
3289 Bits And Pieces bitmasks dfs and similar dp greedy Statement F Manthan, Codefest 19 (open for everyone, rated, Div. 1 + Div. 2) {1208} PROGRAMMING 69357 2600
3244 Rotate Columns (easy version) bitmasks brute force dp greedy sortings Statement E1 Codeforces Round 584 - Dasha Code Championship - Elimination Round (rated, open for everyone, Div. 1 + Div. 2) {1209} PROGRAMMING 69791 2000
2296 Rotate Columns (hard version) bitmasks dp greedy sortings Statement E2 Codeforces Round 584 - Dasha Code Championship - Elimination Round (rated, open for everyone, Div. 1 + Div. 2) {1209} PROGRAMMING 69791 2400
658 To Make 1 bitmasks constructive algorithms dp greedy number theory Statement G Technocup 2020 - Elimination Round 2 {1225} PROGRAMMING 70898 3000
8588 Dr. Evil Underscores bitmasks brute force dfs and similar divide and conquer dp greedy strings trees Statement D Codeforces Round 613 (Div. 2) {1285} PROGRAMMING Codeforces Round #613 (Div. 2) Editorial 1800
7695 Fill The Bag bitmasks greedy Statement D Educational Codeforces Round 82 (Rated for Div. 2) {1303} PROGRAMMING Educational Codeforces Round 82 1800
18314 Adding Powers bitmasks greedy implementation math number theory ternary search Statement C Educational Codeforces Round 83 (Rated for Div. 2) {1312} PROGRAMMING 74640
5331 Team Building bitmasks dp greedy sortings Statement E CodeCraft-20 (Div. 2) {1316} PROGRAMMING 2250.0 Codecraft-20 (Div.2) Editorial 2300
13553 Ehab the Xorcist bitmasks constructive algorithms greedy number theory Statement D Codeforces Round 628 (Div. 2) {1325} PROGRAMMING 1750.0 74235 1700
3436 Perfect Triples bitmasks brute force constructive algorithms divide and conquer greedy implementation math Statement C Codeforces Round 633 (Div. 1) {1338} PROGRAMMING 1500.0 Editorial
9502 Edge Weight Assignment bitmasks constructive algorithms greedy math trees Statement B Codeforces Round 633 (Div. 1) {1338} PROGRAMMING 1000.0 Editorial
8305 Nastya and Scoreboard bitmasks dp greedy Statement B Codeforces Round 637 (Div. 1) - Thanks, Ivan Belonogov! {1340} PROGRAMMING 750.0 Codeforces Round #637 Editorial
9335 Phoenix and Science binary search bitmasks constructive algorithms greedy math Statement D Codeforces Round 638 (Div. 2) {1348} PROGRAMMING 2000.0 Codeforces Round #638 (Div. 2) Editorial 1900
23586 Johnny and Another Rating Drop bitmasks greedy math Statement C Codeforces Round 647 (Div. 2) - Thanks, Algo Muse! {1362} PROGRAMMING 1500.0 Codeforces Round #647 Editorial 1400
13571 AND, OR and square sum bitmasks greedy math Statement D Codeforces Global Round 8 {1368} PROGRAMMING 1750.0 Codeforces Global Round 8: editorial
5431 GameGame bitmasks constructive algorithms dp games greedy math Statement B Codeforces Round 659 (Div. 1) {1383} PROGRAMMING 1000.0 Codeforces Round #659 Editorial
1159 x-prime Substrings bitmasks dp greedy number theory string suffix structures strings Statement F Educational Codeforces Round 94 (Rated for Div. 2) {1400} PROGRAMMING 81942
2675 Two Different bitmasks constructive algorithms divide and conquer greedy Statement F Grakn Forces 2020 {1408} PROGRAMMING 2500.0 Grakn Forces -- Editorial
5029 XOR Inverse bitmasks data structures divide and conquer greedy strings trees Statement C Codeforces Round 673 (Div. 1) {1416} PROGRAMMING 1250.0 Codeforces Round #673 Editorial 2000
35170 XORwice bitmasks greedy math Statement A Codeforces Round 676 (Div. 2) {1421} PROGRAMMING 500.0 Codeforces Round #676 (Div. 2) Editorial
1082 Enormous XOR bitmasks greedy strings two pointers Statement E Codeforces Round 705 (Div. 2) {1493} PROGRAMMING 2750.0 Codeforces Round #705 (Div.2) Editorial
15296 Berland Crossword binary search bitmasks brute force greedy implementation Statement B Educational Codeforces Round 105 (Rated for Div. 2) {1494} PROGRAMMING Educational Codeforces Round 105 Editorial
23152 Box Fitting binary search bitmasks data structures greedy Statement B CodeCraft-21 and Codeforces Round 711 (Div. 2) {1498} PROGRAMMING 1000.0 CodeCraft-21 and Codeforces Round #711 (Div. 2) Editorial
910 Matrix Sorting bitmasks constructive algorithms dfs and similar greedy hashing string suffix structures two pointers Statement C Codeforces Round 707 (Div. 1, based on Moscow Open Olympiad in Informatics) {1500} PROGRAMMING 1500.0 Codeforces Round #707 Editorial 2600
25238 AGAGA XOOORRR bitmasks brute force dp greedy Statement B Codeforces Round 717 (Div. 2) {1516} PROGRAMMING 1000.0 Codeforces round #717 editorial
1833 Stringforces binary search bitmasks data structures dp greedy strings two pointers Statement E Educational Codeforces Round 111 (Rated for Div. 2) {1550} PROGRAMMING Educational Codeforces Round 111 Editorial
13777 Cobb bitmasks brute force greedy math Statement B Codeforces Round 735 (Div. 2) {1554} PROGRAMMING 1250.0 Editorial of Codeforces Round #735 (Div. 2) 1700
9670 Mikasa binary search bitmasks greedy implementation Statement C Codeforces Round 735 (Div. 2) {1554} PROGRAMMING 1750.0 Editorial of Codeforces Round #735 (Div. 2) 1800
6741 Nearest Beautiful Number (easy version) binary search bitmasks brute force constructive algorithms dfs and similar greedy Statement F1 Codeforces Round 739 (Div. 3) {1560} PROGRAMMING 94009 1900
4928 Nearest Beautiful Number (hard version) bitmasks brute force constructive algorithms dfs and similar dp greedy Statement F2 Codeforces Round 739 (Div. 3) {1560} PROGRAMMING 94009 2100
18999 MAX-MEX Cut bitmasks constructive algorithms dp greedy Statement C Codeforces Global Round 16 {1566} PROGRAMMING 1000.0 Codeforces Global Round 16 Editorial
32696 MEXor Mixup bitmasks greedy Statement B Codeforces Round 742 (Div. 2) {1567} PROGRAMMING 1000.0 Codeforces Round #742 Editorial
374 Fix the String *special bitmasks dp greedy Statement E Kotlin Heroes: Episode 8 {1571} PROGRAMMING Kotlin Heroes 8 Editorial
1112 Strange LCS bitmasks dp graphs greedy strings Statement F Technocup 2022 - Elimination Round 2 {1584} PROGRAMMING 2500.0 Editorial for Technocup 2022 — Elimination Round 2 and Codeforces Round #755 (Div. 1, Div. 2) 2600
1916 Bored Bakry bitmasks greedy math two pointers Statement E Codeforces Round 746 (Div. 2) {1592} PROGRAMMING 2500.0 95583
328 Bob's Beautiful Array bitmasks brute force greedy Statement J Bubble Cup 14 - Finals Online Mirror (Unrated, ICPC Rules, Teams Preferred, Div. 1) {1599} PROGRAMMING BubbleCup2021.pdf
3243 Treelabeling bitmasks constructive algorithms dfs and similar games graphs greedy trees Statement D Codeforces Round 754 (Div. 2) {1605} PROGRAMMING 2000.0 tutorial 2100
17875 And It's Non-Zero bitmasks greedy math Statement B Codeforces Global Round 18 {1615} PROGRAMMING 1000.0 Global Round 18 Editorial
7262 BA-String bitmasks brute force dp greedy implementation math shortest paths Statement C Educational Codeforces Round 119 (Rated for Div. 2) {1620} PROGRAMMING 98061
2235 Math Test bitmasks brute force greedy Statement E Educational Codeforces Round 120 (Rated for Div. 2) {1622} PROGRAMMING Educational Codeforces Round 120 Editorial
7567 MinOr Tree bitmasks dfs and similar dsu greedy Statement G Codeforces Round 764 (Div. 3) {1624} PROGRAMMING Codeforces Round #764 (Div. 3) Editorial
18274 Ancient Civilization bitmasks greedy math Statement A Codeforces Round 765 (Div. 2) {1625} PROGRAMMING 500.0 Editorial of Codeforces Round #765 (Div. 2)
14048 Strange Test binary search bitmasks brute force greedy math Statement C Codeforces Round 769 (Div. 2) {1632} PROGRAMMING 1500.0 Editorial of Codeforces Round #769
25803 Min Or Sum bitmasks greedy Statement A Codeforces Round 772 (Div. 2) {1635} PROGRAMMING 500.0 Codeforces Round #772 Editorial
1962 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
12015 Bit Flipping bitmasks constructive algorithms greedy strings Statement B Codeforces Round 782 (Div. 2) {1659} PROGRAMMING 750.0 Codeforces Round #782 (Div. 2) Editorial
1793 MinimizOR binary search bitmasks data structures dp greedy implementation Statement E Codeforces Round 781 (Div. 2) {1665} PROGRAMMING 2250.0 Codeforces Round #781 (Div. 2) Editorial
28835 Maximal AND bitmasks greedy math Statement H Codeforces Round 784 (Div. 4) {1669} PROGRAMMING 102101 1300
954 Anti-Theft Road Planning bitmasks constructive algorithms divide and conquer greedy interactive math Statement F Codeforces Round 785 (Div. 2) {1673} PROGRAMMING 3250.0 Codeforces Round #785 (Div. 2) Editorial
4314 Moving Chips binary search bitmasks dp greedy Statement E Educational Codeforces Round 128 (Rated for Div. 2) {1680} PROGRAMMING 102852
18996 Patchouli's Magical Talisman bitmasks constructive algorithms greedy sortings Statement B Codeforces Round 796 (Div. 2) {1688} PROGRAMMING 750.0 Tutorial
20169 NIT orz! bitmasks greedy Statement A Codeforces Global Round 21 {1696} PROGRAMMING 500.0 Editorial of Codeforces Global Round 21
12698 Good Key, Bad Key bitmasks brute force dp greedy math Statement G Codeforces Round 806 (Div. 4) {1703} PROGRAMMING 104786
2446 Mark and Professor Koro binary search bitmasks combinatorics data structures greedy Statement E Codeforces Round 807 (Div. 2) {1705} PROGRAMMING 2500.0 Codeforces Round #807 (Div 2.) Editorial
33381 Minimum Varied Number bitmasks brute force greedy Statement C Codeforces Round 811 (Div. 3) {1714} PROGRAMMING Codeforces Round #811 (Div. 3) Editorial
6059 2+ doors 2-sat bitmasks graphs greedy schedules Statement D Codeforces Round 816 (Div. 2) {1715} PROGRAMMING 2250.0 Codeforces Round #816 (Div. 2) editorial
7663 Maximum AND bitmasks brute force divide and conquer greedy math sortings Statement D Educational Codeforces Round 134 (Rated for Div. 2) {1721} PROGRAMMING 106416
14113 Even-Odd XOR bitmasks constructive algorithms greedy Statement G Codeforces Round 817 (Div. 4) {1722} PROGRAMMING 106478 1500
7519 Sheikh (Easy version) binary search bitmasks greedy two pointers Statement C1 Codeforces Round 830 (Div. 2) {1732} PROGRAMMING 1000.0 108327 1800
3058 Sheikh (Hard Version) binary search bitmasks brute force greedy implementation two pointers Statement C2 Codeforces Round 830 (Div. 2) {1732} PROGRAMMING 1000.0 108327 2100
13200 Orray bitmasks brute force greedy math Statement G Codeforces Round 827 (Div. 4) {1742} PROGRAMMING 107962
10240 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
16982 Absolute Maximization bitmasks constructive algorithms greedy math Statement A Codeforces Round 840 (Div. 2) and Enigma 2022 - Cybros LNMIIT {1763} PROGRAMMING 500.0 Codeforces Round #840 (Div. 2) and Enigma 2022 — Cybros LNMIIT Editorial
2714 The Harmonization of XOR bitmasks constructive algorithms greedy math Statement E TypeDB Forces 2023 (Div. 1 + Div. 2, Rated, Prizes!) {1787} PROGRAMMING 2250.0 TypeDB Forces 2023 (Div. 1 + Div. 2, Rated, Prizes!) Editorial
32391 Mr. Perfectly Fine bitmasks greedy implementation Statement C Codeforces Round 871 (Div. 4) {1829} PROGRAMMING Codeforces Round 871 (Div. 4) Editorial 800
25342 Tenzing and Books bitmasks greedy math Statement B CodeTON Round 5 (Div. 1 + Div. 2, Rated, Prizes!) {1842} PROGRAMMING 500.0 CodeTON Round 5 Editorial
5617 Rudolf and CodeVid-23 bitmasks dp graphs greedy shortest paths Statement G Codeforces Round 883 (Div. 3) {1846} PROGRAMMING
1026 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
14730 Vampiric Powers, anyone? bitmasks brute force data structures dp greedy Statement C Codeforces Round 882 (Div. 2) {1847} PROGRAMMING 1500.0 Tutorial
22257 Hamon Odyssey bitmasks greedy implementation Statement B Codeforces Round 882 (Div. 2) {1847} PROGRAMMING 1000.0 Tutorial
877 XOR Partition binary search bitmasks data structures divide and conquer greedy trees Statement F Educational Codeforces Round 152 (Rated for Div. 2) {1849} PROGRAMMING 118752
7373 Lisa and the Martians bitmasks data structures greedy math sortings strings trees Statement F Codeforces Round 888 (Div. 3) {1851} PROGRAMMING 118667
2739 Candy Party (Hard Version) bitmasks constructive algorithms dp graphs greedy implementation math Statement B2 Codeforces Round 896 (Div. 1) {1868} PROGRAMMING 750.0 Codeforces Round 896 (Div. 1, Div. 2) Editorial
8299 Candy Party (Easy Version) bitmasks constructive algorithms graphs greedy implementation math Statement B1 Codeforces Round 896 (Div. 1) {1868} PROGRAMMING 500.0 Codeforces Round 896 (Div. 1, Div. 2) Editorial
16065 Friendly Arrays bitmasks greedy math Statement B CodeTON Round 6 (Div. 1 + Div. 2, Rated, Prizes!) {1870} PROGRAMMING 750.0 CodeTON Round 6 (Div. 1 + Div. 2, Rated, Prizes!) Editorial
13852 Jellyfish and Green Apple bitmasks greedy math number theory Statement C Codeforces Round 901 (Div. 2) {1875} PROGRAMMING 1000.0 Codeforces Round 901 (Div. 1, Div. 2) Editorial
20662 Iva & Pav binary search bitmasks data structures greedy Statement E Codeforces Round 900 (Div. 3) {1878} PROGRAMMING Codeforces round #900 (Div.3) Editorial
17390 Sets and Union bitmasks brute force constructive algorithms greedy Statement B Codeforces Round 899 (Div. 2) {1882} PROGRAMMING 1000.0 Codeforces Round 899 (Div. 2) Editorial
7063 Tree XOR bitmasks dfs and similar dp greedy trees Statement D Codeforces Round 899 (Div. 2) {1882} PROGRAMMING 2000.0 Codeforces Round 899 (Div. 2) Editorial
9888 Look Back bitmasks greedy Statement E Codeforces Round 905 (Div. 3) {1883} PROGRAMMING 2500.0 Codeforces Round #905 (Div. 1, Div. 2, Div. 3) Editorial
7083 Maximum And Queries (easy version) binary search bitmasks brute force greedy Statement D1 Codeforces Round 912 (Div. 2) {1903} PROGRAMMING 1500.0 Codeforces Round #912 (Div. 2) Editorial
14805 StORage room bitmasks brute force constructive algorithms greedy Statement B Codeforces Round 912 (Div. 2) {1903} PROGRAMMING 1000.0 Codeforces Round #912 (Div. 2) Editorial
17451 Game with Multiset binary search bitmasks greedy Statement C Educational Codeforces Round 160 (Rated for Div. 2) {1913} PROGRAMMING 123493
16586 XOR-distance bitmasks dp greedy implementation math Statement C Codeforces Round 922 (Div. 2) {1918} PROGRAMMING 1250.0 Codeforces Round #922 (Div. 2) Editorial
18320 Vlad and Division bitmasks greedy Statement D Codeforces Round 928 (Div. 4) {1926} PROGRAMMING 126132
2065 Sasha and the Happy Tree Cutting bitmasks brute force dp fft graphs greedy trees Statement E Codeforces Round 926 (Div. 2) {1929} PROGRAMMING 2500.0 Codeforces Round #926 (Div. 2) Editorial.
4127 XOR Break --- Solo Version bitmasks constructive algorithms greedy Statement D1 Codeforces Round 931 (Div. 2) {1934} PROGRAMMING 1500.0 Tutorial
1748 XOR Break --- Game Version bitmasks games greedy interactive Statement D2 Codeforces Round 931 (Div. 2) {1934} PROGRAMMING 1250.0 Tutorial
1645 Distance Learning Courses in MAC binary search bitmasks data structures greedy implementation math Statement E Codeforces Round 932 (Div. 2) {1935} PROGRAMMING 2500.0 Codeforces Round #932 (Div. 2) Editorial
8637 Bitwise Operation Wizard bitmasks constructive algorithms greedy interactive math Statement A Codeforces Round 930 (Div. 1) {1936} PROGRAMMING 500.0 Codeforces Round 930 (Div. 1, Div. 2) Editorial
622 Bitwise Paradox bitmasks data structures greedy two pointers Statement D Codeforces Round 930 (Div. 1) {1936} PROGRAMMING 2000.0 Codeforces Round 930 (Div. 1, Div. 2) Editorial
5591 Birthday Gift bitmasks brute force constructive algorithms greedy implementation Statement D Codeforces Round 936 (Div. 2) {1946} PROGRAMMING 1750.0 Codeforces Round #936 (Div. 2) Editorial
4753 Nene and the Mex Operator bitmasks brute force constructive algorithms divide and conquer dp greedy implementation Statement D Codeforces Round 939 (Div. 2) {1956} PROGRAMMING 1750.0 [Editorial] Codeforces Round 939 (Div. 2)
20360 A BIT of a Construction bitmasks constructive algorithms greedy implementation Statement B Codeforces Round 940 (Div. 2) and CodeCraft-23 {1957} PROGRAMMING 1000.0 Codeforces Round #940 and CodeCraft-23 (Div. 2) Editorial 1100
8085 Missing Subsequence Sum bitmasks constructive algorithms greedy number theory Statement B Codeforces Round 941 (Div. 1) {1965} PROGRAMMING 1250.0 Codeforces Round #941 (Div. 1, Div. 2) Editorial 1800
16778 Cat, Fox and the Lonely Array binary search bitmasks data structures greedy math two pointers Statement B Codeforces Round 945 (Div. 2) {1973} PROGRAMMING 1000.0 Editorial for Codeforces Round #945 (Div. 2) 1300
19862 Binary Colouring bitmasks constructive algorithms greedy math Statement B Codeforces Round 948 (Div. 2) {1977} PROGRAMMING 1250.0 129858 1100
2333 XORificator bitmasks brute force greedy hashing Statement D Codeforces Round 948 (Div. 2) {1977} PROGRAMMING 2000.0 129858 2300
7833 Fixing a Binary String bitmasks brute force constructive algorithms greedy hashing strings Statement D Codeforces Round 951 (Div. 2) {1979} PROGRAMMING 2000.0 Codeforces Round 951 (Div. 2) Editorial
26361 XOR Sequences bitmasks greedy Statement B Codeforces Round 951 (Div. 2) {1979} PROGRAMMING 1000.0 Codeforces Round 951 (Div. 2) Editorial
6329 Turtle and an Incomplete Sequence bitmasks constructive algorithms greedy implementation math Statement C Codeforces Round 949 (Div. 2) {1981} PROGRAMMING 1500.0 Simplified Chinese Tutorial
20243 Increasing Sequence with Fixed OR bitmasks constructive algorithms greedy Statement C Codeforces Round 958 (Div. 2) {1988} PROGRAMMING 1000.0 Editorial of Codeforces Round 958 (Div. 2)
23267 Substring and Subsequence bitmasks brute force dp graphs greedy hashing strings trees Statement B Educational Codeforces Round 167 (Rated for Div. 2) {1989} PROGRAMMING Educational Codeforces Round 167 Editorial
7694 Grid Puzzle bitmasks dp greedy Statement D Codeforces Round 960 (Div. 2) {1990} PROGRAMMING 1750.0 Video Tutorial
7869 Prime XOR Coloring bitmasks constructive algorithms graphs greedy math number theory Statement D Pinely Round 4 (Div. 1 + Div. 2) {1991} PROGRAMMING 1500.0 Video Tutorial
18870 AND Reconstruction bitmasks constructive algorithms greedy Statement B Pinely Round 4 (Div. 1 + Div. 2) {1991} PROGRAMMING 500.0 Video Tutorial
19429 Fun Game bitmasks constructive algorithms greedy math Statement B Codeforces Round 959 sponsored by NEAR (Div. 1 + Div. 2) {1994} PROGRAMMING 1000.0 Video Tutorial
5470 Wooden Game bitmasks greedy math trees Statement E Codeforces Round 959 sponsored by NEAR (Div. 1 + Div. 2) {1994} PROGRAMMING 2000.0 Video Tutorial
2877 Cases bitmasks brute force combinatorics dfs and similar dp graphs greedy strings Statement D Codeforces Round 961 (Div. 2) {1995} PROGRAMMING 2250.0 Video Tutorial
25821 Find Minimum Operations bitmasks greedy math Statement A Codeforces Round 976 (Div. 2) and Divide By Zero 9.0 {2020} PROGRAMMING 500.0 Tutorial for Codeforces Round 976 (Div. 2) and Divide By Zero 9.0
15081 Kevin and Binary Strings bitmasks brute force greedy strings Statement C Codeforces Global Round 28 {2048} PROGRAMMING 1000.0 Tutorial
13696 Trip to the Olympiad bitmasks constructive algorithms greedy math Statement C Hello 2025 {2057} PROGRAMMING 1500.0
3938 Kevin and And bitmasks brute force dp greedy Statement E IAEPC Preliminary Contest (Codeforces Round 999, Div. 1 + Div. 2) {2061} PROGRAMMING 2000.0 IAEPC Preliminary Contest (Codeforces Round 999, Div. 1 + Div. 2) Editorial
5819 Eating binary search bitmasks data structures greedy two pointers Statement D Codeforces Round 1005 (Div. 2) {2064} PROGRAMMING 1750.0 Codeforces Round 1005 (Div. 2) Editorial
19460 Creating Keys for StORages Has Become My Main Skill bitmasks constructive algorithms greedy Statement C Codeforces Round 1006 (Div. 3) {2072} PROGRAMMING Codeforces Round 1006 (Div. 3) Editorial
21908 XOR and Triangle binary search bitmasks brute force greedy Statement C Codeforces Round 1009 (Div. 3) {2074} PROGRAMMING Codeforces Round 1009 (Div. 3) — Editorial
5758 Equalization bitmasks brute force dp greedy math Statement D Educational Codeforces Round 176 (Rated for Div. 2) {2075} PROGRAMMING Educational Codeforces Round 176 Editorial
353 Quaternary Matrix bitmasks greedy Statement C Codeforces Round 1010 (Div. 1, Unrated) {2081} PROGRAMMING 1750.0 Codeforces Round 1010 (Div. 1, Div. 2, based on Zhili Cup 2025) Editorial
13466 Serval and The Formula bitmasks constructive algorithms greedy Statement C Codeforces Round 1011 (Div. 2) {2085} PROGRAMMING 1250.0 Codeforces Round #1011 (Div. 2) Editorial
5856 Hackers and Neural Networks bitmasks brute force greedy Statement F Codeforces Round 1016 (Div. 3) {2093} PROGRAMMING Codeforces Round 1016 (Div. 3) Editorial
14479 SUMdamental Decomposition bitmasks constructive algorithms greedy implementation math Statement B Codeforces Round 1022 (Div. 2) {2108} PROGRAMMING 1250.0 Codeforces Round 1022 Editorial
17232 Slice to Survive bitmasks greedy Statement B Codeforces Round 1025 (Div. 2) {2109} PROGRAMMING 1000.0 Codeforces Round 1025 (Div. 2) Editorial
18346 Make It Beautiful bitmasks greedy math Statement C Codeforces Round 1030 (Div. 2) {2118} PROGRAMMING 1000.0 Codeforces Round 1030 (Div. 2) Editorial
698 And Constraint bitmasks dp greedy implementation Statement E Codeforces Round 1035 (Div. 2) {2119} PROGRAMMING 2500.0 Codeforces Round 1035 (Div. 2) Editorial
4004 Max Sum OR (Hard Version) bitmasks constructive algorithms divide and conquer greedy Statement D2 Codeforces Round 1052 (Div. 2) {2146} PROGRAMMING 1000.0 Codeforces Round 1052 (Div. 2) Editorial
10346 Max Sum OR (Easy Version) bitmasks constructive algorithms divide and conquer greedy trees Statement D1 Codeforces Round 1052 (Div. 2) {2146} PROGRAMMING 1500.0 Codeforces Round 1052 (Div. 2) Editorial
2106 Maximum OR Popcount binary search bitmasks brute force data structures greedy Statement E Codeforces Global Round 29 (Div. 1 + Div. 2) {2147} PROGRAMMING 2500.0
3470 Binary Wine bitmasks greedy Statement C Codeforces Round 1064 (Div. 1) {2165} PROGRAMMING 1500.0 148452
2292 Sakura Adachi and Optimal Sequences bitmasks combinatorics greedy math Statement G Codeforces Round 1065 (Div. 3) {2171} PROGRAMMING Codeforces Round 1065 (Div. 3) Editorial
11720 Renako Amaori and XOR Game (hard version) bitmasks games greedy Statement C2 Codeforces Round 1065 (Div. 3) {2171} PROGRAMMING Codeforces Round 1065 (Div. 3) Editorial
3588 Taiga's Carry Chains bitmasks brute force dp greedy Statement D Codeforces Round 1068 (Div. 2) {2173} PROGRAMMING 1750.0
22733 Optimal Shifts bitmasks greedy strings Statement B Codeforces Round 1070 (Div. 2) {2176} PROGRAMMING 1000.0 Codeforces Round 1070 (Div.2) Editorial
13361 Blackslex and Penguin Civilization bitmasks constructive algorithms greedy math Statement D Codeforces Round 1071 (Div. 3) {2179} PROGRAMMING Codeforces Round 1071 (Div. 3) Editorial
6386 XOR-factorization bitmasks constructive algorithms dp greedy number theory Statement C Codeforces Global Round 31 (Div. 1 + Div. 2) {2180} PROGRAMMING 1500.0 Codeforces Global Round 31
5179 Shortest Statement Ever bitmasks constructive algorithms dp greedy Statement B Codeforces Round 1077 (Div. 1) {2187} PROGRAMMING 1250.0 Codeforces Round 1077 (Div. 1, Div. 2) Editorial
274 Fuzzy Concatenation (Easy Version) binary search bitmasks brute force data structures greedy string suffix structures Statement E1 Codeforces Round 1079 (Div. 1) {2196} PROGRAMMING 2000.0 Tutorial
6736 Test Generator binary search bitmasks greedy math Statement C Educational Codeforces Round 187 (Rated for Div. 2) {2203} PROGRAMMING Educational Codeforces Round 187 Editorial
78 EXPloration, EXPloitation, and Gain Some EXPerience! bitmasks brute force dp greedy implementation Statement D Codeforces Round 1092 (Unrated, Div. 1, Based on THUPC 2026 — Finals) {2215} PROGRAMMING 2750.0
589 Interval Game bitmasks combinatorics dp games greedy math probabilities Statement F Codeforces Round 1091 (Div. 2) and CodeCraft 26 {2217} PROGRAMMING 2750.0