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18703 Longest Regular Bracket Sequence constructive algorithms data structures dp greedy sortings strings Statement C Codeforces Beta Round 5 {5} PROGRAMMING C, D и E с CBR5 - разбор 1900
945 Tricky and Clever Password binary search constructive algorithms data structures greedy hashing strings Statement E Codeforces Beta Round 30 (Codeforces format) {30} PROGRAMMING Codeforces Beta Round #30. Tutorial for problem A 2700
661 Director constructive algorithms greedy Statement E School Team Contest 3 (Winter Computer School 2010/11) {45} PROGRAMMING 2100
1073 Russian Roulette constructive algorithms greedy Statement C Codeforces Beta Round 80 (Div. 1 Only) {103} PROGRAMMING Tutorial 1900
11096 Lucky String constructive algorithms strings Statement B Codeforces Beta Round 84 (Div. 2 Only) {110} PROGRAMMING Codeforces Beta Round #84 - Analysis 1100
2914 String brute force constructive algorithms hashing implementation string suffix structures strings Statement B Codeforces Beta Round 94 (Div. 1 Only) {128} PROGRAMMING 3219 2200
673 Headquarters constructive algorithms math Statement A Croc Champ 2012 - Final {183} PROGRAMMING CROC Champ 2012 — Round 3 (Editorial) 1900
675 Hamming Distance constructive algorithms greedy math matrices Statement C Codeforces Round 122 (Div. 1) {193} PROGRAMMING Editoral Codeforces Round #122 2400
10273 XOR and OR constructive algorithms implementation math Statement C Codeforces Round 173 (Div. 2) {282} PROGRAMMING Round #173 — Editorial 1600
8181 Removing Columns brute force constructive algorithms implementation Statement C Codeforces Round 283 (Div. 2) {496} PROGRAMMING 15208 1600
9581 Vitaly and Strings constructive algorithms strings Statement A Codeforces Round 293 (Div. 2) {518} PROGRAMMING Codeforces Round #293 (Div.2) Editorial 1600
10314 Pasha and String constructive algorithms greedy math strings Statement B Codeforces Round 297 (Div. 2) {525} PROGRAMMING Codeforces Round #297 (Div.2) Editorial 1500
2453 Correcting Mistakes constructive algorithms dp greedy hashing strings two pointers Statement E VK Cup 2015 - Round 2 (unofficial online mirror, Div. 1 only) {533} PROGRAMMING Разбор VK Cup Round 2 1800
4069 ZgukistringZ brute force constructive algorithms implementation strings Statement B Codeforces Round 307 (Div. 2) {551} PROGRAMMING Tutorial 1800
740 CNF 2 constructive algorithms dfs and similar graphs greedy Statement C Codeforces Round 317 [AimFund Thanks-Round] (Div. 1) {571} PROGRAMMING Codeforces Round #317 [AimFund Thanks-Round] Editorial 2600
6554 Marina and Vasya constructive algorithms greedy strings Statement C Codeforces Round 324 (Div. 2) {584} PROGRAMMING Tutorial 1700
7184 Make Palindrome constructive algorithms greedy strings Statement C Educational Codeforces Round 2 {600} PROGRAMMING Editorial 1800
764 New Year and Forgotten Tree constructive algorithms flows graphs Statement H Good Bye 2015 {611} PROGRAMMING Tutorial 3000
11654 War of the Corporations constructive algorithms greedy strings Statement B Codeforces Round 342 (Div. 2) {625} PROGRAMMING Codeforces Round #342 (Div. 2) : editorial 1300
936 Restore a Number brute force constructive algorithms strings Statement F Codeforces Round 350 (Div. 2) {670} PROGRAMMING Codeforces Round #350 (Div.2) Editorial 2200
18635 Different is Good constructive algorithms implementation strings Statement B Codeforces Round 352 (Div. 2) {672} PROGRAMMING 1000
9935 Letters Cyclic Shift constructive algorithms greedy implementation strings Statement A AIM Tech Round 3 (Div. 1) {708} PROGRAMMING Editorial 1200
2952 Hidden Word brute force constructive algorithms implementation strings Statement C Canada Cup 2016 {725} PROGRAMMING Canada Cup Editorial 1600
3278 Delete Them constructive algorithms implementation Statement H 2016-2017 ACM-ICPC, NEERC, Southern Subregional Contest (Online Mirror, ACM-ICPC Rules, Teams Preferred) {730} PROGRAMMING Разбор задач (видео, по-русски) 1400
2080 Santa Claus and a Palindrome constructive algorithms data structures greedy Statement D Technocup 2017 - Elimination Round 3 {748} PROGRAMMING Codeforces Round 389 (Div.2) Editorial 2000
1118 Vladik and chat brute force constructive algorithms dp implementation strings Statement C Codeforces Round 390 (Div. 2) {754} PROGRAMMING 2200
2963 Ability To Convert constructive algorithms dp greedy math strings Statement D Codeforces Round 392 (Div. 2) {758} PROGRAMMING Codeforces Round #392 (Div. 2) Editorial 1900
35040 Mahmoud and Longest Uncommon Subsequence constructive algorithms strings Statement A Codeforces Round 396 (Div. 2) {766} PROGRAMMING Codeforces round #396 editorial 1000
7247 Bear and Different Names constructive algorithms greedy Statement B VK Cup 2017 - Round 1 {771} PROGRAMMING VK Cup 2017 Round 1 and CF Round 405 — Editorial 1500
24077 Mike and palindrome brute force constructive algorithms strings Statement A Codeforces Round 410 (Div. 2) {798} PROGRAMMING Codeforces Round #410 (Div. 2) Editorial 1100
11278 Valued Keys constructive algorithms greedy strings Statement B Codeforces Round 409 (rated, Div. 2, based on VK Cup 2017 Round 2) {801} PROGRAMMING 1000
557 Fake News (medium) constructive algorithms strings Statement G2 Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} PROGRAMMING helvetic-coding-contest-2017-editorial.pdf 2200
544 Fake News (medium) constructive algorithms strings Statement H Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} PROGRAMMING helvetic-coding-contest-2017-editorial.pdf 2400
1978 Restoration of string constructive algorithms graphs implementation Statement D Технокубок 2018 - Отборочный Раунд 3 {886} PROGRAMMING Editorial Codeforces Round 445 (and Technocup 2018 — Elimination Round 3) 2000
1445 Picking Strings constructive algorithms implementation strings Statement D VK Cup 2018 - Round 1 {923} PROGRAMMING VK Cup 2018 Round 1 and CF Round #470 (div. 1 & 2) editorial 2500
1287 Lock Puzzle constructive algorithms implementation strings Statement C Codeforces Round 467 (Div. 1) {936} PROGRAMMING Codeforces Round #467, Editorial 2500
6755 Phone Numbers constructive algorithms implementation strings Statement C Codeforces Round 466 (Div. 2) {940} PROGRAMMING [Editorial] Codeforces Round #466 (Div. 2) 1500
7310 A Tide of Riverscape constructive algorithms strings Statement B Codeforces Round 487 (Div. 2) {989} PROGRAMMING Codeforces Round #487 (Div. 2) Editorial 1300
433 AB-Strings constructive algorithms strings Statement D Codeforces Round 500 (Div. 1) [based on EJOI] {1012} PROGRAMMING 60920 2700
518 Chips Puzzle constructive algorithms implementation math Statement E Mail.Ru Cup 2018 Round 1 {1054} PROGRAMMING Editorial 2400
11155 Oh Those Palindromes constructive algorithms strings Statement A Codeforces Round 516 (Div. 1, by Moscow Team Olympiad) {1063} PROGRAMMING Editorial 1400
17821 Letters Rearranging constructive algorithms greedy sortings strings Statement B Educational Codeforces Round 56 (Rated for Div. 2) {1093} PROGRAMMING 63877 900
4562 Sasha and One More Name constructive algorithms hashing strings Statement B Codeforces Round 539 (Div. 1) {1109} PROGRAMMING Codeforces Round #539 Editorial 1800
2405 The minimal unique substring constructive algorithms math strings Statement B Codeforces Round 559 (Div. 1) {1158} PROGRAMMING 66993 2200
4545 Archaeology brute force constructive algorithms greedy strings Statement E Codeforces Global Round 4 {1178} PROGRAMMING E 1900
5486 Print a 1337-string... combinatorics constructive algorithms math strings Statement D Educational Codeforces Round 70 (Rated for Div. 2) {1202} PROGRAMMING 68972 1900
12015 Swap Letters constructive algorithms greedy Statement C Codeforces Round 585 (Div. 2) {1215} PROGRAMMING Codeforces Round #585 Editorial 1500
951 Middle-Out constructive algorithms greedy strings Statement E Dasha Code Championship - Novosibirsk Finals Round (only for onsite-finalists) {1231} PROGRAMMING Dasha Code Championship Finals and Mirror Round 588 Editorial 2000
3655 Equalizing Two Strings constructive algorithms sortings strings Statement F Codeforces Round 598 (Div. 3) {1256} PROGRAMMING Codeforces Round #598 (Div. 3) Editorial 2200
16019 Beautiful String constructive algorithms greedy Statement A Codeforces Round 604 (Div. 2) {1265} PROGRAMMING Codeforces Round #604 Editorial 1000
3387 Lexicography constructive algorithms strings Statement L 2019-2020 ICPC, NERC, Northern Eurasia Finals (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1267} PROGRAMMING nerc-2019-tutorial.pdf 1800
9166 Long Beautiful Integer constructive algorithms greedy implementation strings Statement A Codeforces Round 609 (Div. 1) {1268} PROGRAMMING Codeforces Round #609 — Editorial 1700
2448 Enchanted Artifact constructive algorithms interactive strings Statement D Codeforces Round 610 (Div. 2) {1282} PROGRAMMING 72461 2300
1618 Madhouse (Easy version) brute force constructive algorithms interactive math Statement C1 Codeforces Round 612 (Div. 1) {1286} PROGRAMMING Codeforces Round #612 - Editorial 2400
767 Madhouse (Hard version) brute force constructive algorithms hashing interactive math Statement C2 Codeforces Round 612 (Div. 1) {1286} PROGRAMMING Codeforces Round #612 - Editorial 2900
7359 Irreducible Anagrams binary search constructive algorithms data structures strings two pointers Statement B Codeforces Round 616 (Div. 1) {1290} PROGRAMMING 1000.0 Codeforces Round #616 Editorial 1900
18854 Longest Palindrome brute force constructive algorithms greedy implementation strings Statement B Codeforces Round 620 (Div. 2) {1304} PROGRAMMING 1000.0 Codeforces Round #620 (Div. 2) Editorial 1100
12533 Kuroni and Simple Strings constructive algorithms greedy strings two pointers Statement B Ozon Tech Challenge 2020 (Div.1 + Div.2, Rated, T-shirts + prizes!) {1305} PROGRAMMING 1000.0 Ozon Tech Challenge 2020 Editorial 1300
11815 String Modification brute force constructive algorithms implementation sortings strings Statement B CodeCraft-20 (Div. 2) {1316} PROGRAMMING 1000.0 Codecraft-20 (Div.2) Editorial 1400
550 Dreamoon Likes Strings constructive algorithms data structures Statement D Codeforces Round 631 (Div. 1) - Thanks, Denis aramis Shitov! {1329} PROGRAMMING 2000.0 Codeforces Round #631 Editorial 3000
24698 Binary Period constructive algorithms strings Statement B Educational Codeforces Round 86 (Rated for Div. 2) {1342} PROGRAMMING 76633 1200
15593 Phoenix and Distribution constructive algorithms greedy strings Statement C Codeforces Round 638 (Div. 2) {1348} PROGRAMMING 1500.0 Codeforces Round #638 (Div. 2) Editorial 1600
19709 Binary String Reconstruction constructive algorithms dfs and similar math Statement F Codeforces Round 640 (Div. 4) {1352} PROGRAMMING 77161 1500
13666 Spy-string bitmasks brute force constructive algorithms dp hashing strings Statement F Codeforces Round 644 (Div. 3) {1360} PROGRAMMING Codeforces Round #644 (Div. 3) Editorial 1700
8903 Task On The Board constructive algorithms greedy implementation sortings Statement D Codeforces Round 650 (Div. 3) {1367} PROGRAMMING Codeforces Round #650 (Div. 3) Editorial
21687 Codeforces Subsequences brute force constructive algorithms greedy math strings Statement B Codeforces Global Round 8 {1368} PROGRAMMING 1000.0 Codeforces Global Round 8: editorial
55142 01 Game brute force constructive algorithms dp games implementation strings Statement B Educational Codeforces Round 90 (Rated for Div. 2) {1373} PROGRAMMING Educational Codeforces Round 90 Editorial
21858 Prefix Flip (Easy Version) constructive algorithms data structures strings Statement A1 Codeforces Round 658 (Div. 1) {1381} PROGRAMMING 500.0 Codeforces Round #658 Editorial 1300
14471 Prefix Flip (Hard Version) constructive algorithms data structures strings two pointers Statement A2 Codeforces Round 658 (Div. 1) {1381} PROGRAMMING 500.0 Codeforces Round #658 Editorial 1700
19823 Common Prefixes constructive algorithms greedy strings Statement A Codeforces Round 659 (Div. 2) {1384} PROGRAMMING 500.0 Codeforces Round #659 Editorial
9981 Omkar and Bed Wars constructive algorithms dp greedy math strings Statement D Codeforces Global Round 10 {1392} PROGRAMMING 1500.0 Codeforces Global Round 10 — Editorial
18616 Binary String Reconstruction 2-sat constructive algorithms greedy strings Statement C Educational Codeforces Round 94 (Rated for Div. 2) {1400} PROGRAMMING 81942
28040 String Similarity brute force constructive algorithms strings Statement A Educational Codeforces Round 94 (Rated for Div. 2) {1400} PROGRAMMING 81942
13601 Palindromifier constructive algorithms strings Statement C Codeforces Round 676 (Div. 2) {1421} PROGRAMMING 1500.0 Codeforces Round #676 (Div. 2) Editorial
21036 Reverse Binary Strings constructive algorithms greedy Statement B Educational Codeforces Round 97 (Rated for Div. 2) {1437} PROGRAMMING 84149
18514 Avoid Trygub constructive algorithms sortings Statement A Codeforces Global Round 12 {1450} PROGRAMMING 500.0 Codeforces Global Round 12 Editorial
19025 String Generation constructive algorithms greedy Statement A Codeforces Round 689 (Div. 2, based on Zed Code Competition) {1461} PROGRAMMING 500.0 Codeforces Round #689 (Div. 2). Editorial
5972 Unusual Matrix 2-sat constructive algorithms greedy Statement F Codeforces Round 697 (Div. 3) {1475} PROGRAMMING Codeforces Round #697 (Div. 3) Editorial
12492 Fence Painting brute force constructive algorithms greedy implementation Statement C Codeforces Round 699 (Div. 2) {1481} PROGRAMMING 1500.0 Codeforces Round #699 (Div. 2) Editorial
4911 AB Graph constructive algorithms graphs greedy implementation strings Statement D Codeforces Round 699 (Div. 2) {1481} PROGRAMMING 2000.0 Codeforces Round #699 (Div. 2) Editorial
22382 Split it! brute force constructive algorithms greedy strings Statement A Codeforces Round 706 (Div. 2) {1496} PROGRAMMING 500.0 Codeforces Round #706 Editorial
22020 Domino on Windowsill constructive algorithms math Statement A Educational Codeforces Round 106 (Rated for Div. 2) {1499} PROGRAMMING Educational Codeforces Round 106 Editorial
26905 Flip the Bits constructive algorithms greedy implementation math Statement B Codeforces Round 712 (Div. 2) {1504} PROGRAMMING 1000.0 Codeforces Round #712 Editorial 1200
22882 Déjà Vu constructive algorithms strings Statement A Codeforces Round 712 (Div. 2) {1504} PROGRAMMING 500.0 Codeforces Round #712 Editorial 800
6715 Binary Literature constructive algorithms greedy implementation math strings two pointers Statement A Codeforces Round 715 (Div. 1) {1508} PROGRAMMING 750.0 Codeforces Round #715 Editorial
12544 Min Cost String brute force constructive algorithms dfs and similar graphs greedy Statement D Educational Codeforces Round 107 (Rated for Div. 2) {1511} PROGRAMMING 89634
21971 A-B Palindrome constructive algorithms implementation strings Statement C Codeforces Round 713 (Div. 3) {1512} PROGRAMMING Codeforces Round #713 (Div. 3) Editorial
2833 Kill Anton brute force constructive algorithms data structures math strings Statement D Codeforces Round 723 (Div. 2) {1526} PROGRAMMING 2250.0 Codeforces Round #723 (Div. 2) Editorial
1531 Oolimry and Suffix Array combinatorics constructive algorithms math string suffix structures Statement E Codeforces Round 723 (Div. 2) {1526} PROGRAMMING 2500.0 Codeforces Round #723 (Div. 2) Editorial
3363 Minimax constructive algorithms greedy implementation strings Statement E Codeforces Round 733 (Div. 1 + Div. 2, based on VK Cup 2021 - Elimination (Engine)) {1530} PROGRAMMING 2000.0 Codeforces Round #733 Editorial (all problems)
15477 Another Problem About Dividing Numbers constructive algorithms number theory Statement D Codeforces Round 725 (Div. 3) {1538} PROGRAMMING Codeforces Round #725 (Div. 3) Editorial
10660 Diane constructive algorithms greedy strings Statement D Codeforces Round 735 (Div. 2) {1554} PROGRAMMING 2000.0 Editorial of Codeforces Round #735 (Div. 2) 1800
21377 MIN-MEX Cut bitmasks constructive algorithms dp Statement B Codeforces Global Round 16 {1566} PROGRAMMING 750.0 Codeforces Global Round 16 Editorial
39568 AB Balance constructive algorithms strings Statement A Educational Codeforces Round 116 (Rated for Div. 2) {1606} PROGRAMMING 96454
17039 Forbidden Subsequence constructive algorithms sortings strings Statement A Codeforces Round 761 (Div. 2) {1617} PROGRAMMING 750.0 Editorial for Codeforces Round #761 (Div. 2)
4655 Masha-forgetful brute force constructive algorithms dp hashing implementation strings Statement E Codeforces Round 764 (Div. 3) {1624} PROGRAMMING Codeforces Round #764 (Div. 3) Editorial
27054 Division by Two and Permutation constructive algorithms flows graph matchings greedy math Statement C Codeforces Round 764 (Div. 3) {1624} PROGRAMMING Codeforces Round #764 (Div. 3) Editorial
22848 Quality vs Quantity brute force constructive algorithms greedy sortings two pointers Statement B Codeforces Round 774 (Div. 2) {1646} PROGRAMMING 1000.0 Codeforces Round #774 (Div. 2) Editorial 800
12084 Bit Flipping bitmasks constructive algorithms greedy strings Statement B Codeforces Round 782 (Div. 2) {1659} PROGRAMMING 750.0 Codeforces Round #782 (Div. 2) Editorial
6983 Cyclic Rotation constructive algorithms greedy implementation two pointers Statement D Codeforces Global Round 20 {1672} PROGRAMMING 1000.0 Global Round 20 Editorial 1700
16508 I love AAAB constructive algorithms implementation Statement B Codeforces Global Round 20 {1672} PROGRAMMING 500.0 Global Round 20 Editorial 800
304 Hard Cut constructive algorithms divide and conquer math Statement H Codeforces Round 792 (Div. 1 + Div. 2) {1684} PROGRAMMING 3250.0 Codeforces Round #792 (Div. 1 + Div. 2) Editorial 3400
17361 Sum of Substrings brute force constructive algorithms greedy math strings Statement C CodeCraft-22 and Codeforces Round 795 (Div. 2) {1691} PROGRAMMING 1250.0 Editorial for CodeCraft-22 and Codeforces Round #795 (Div. 2)
20775 Paranoid String constructive algorithms greedy Statement B Codeforces Round 800 (Div. 2) {1694} PROGRAMMING 1000.0 Codeforces Round #800 Editorial 1200
1164 Tree Recovery bitmasks brute force constructive algorithms dfs and similar dsu graphs trees Statement F Codeforces Global Round 21 {1696} PROGRAMMING 2500.0 Editorial of Codeforces Global Round 21
15905 awoo's Favorite Problem constructive algorithms data structures dp greedy implementation strings two pointers Statement C Educational Codeforces Round 130 (Rated for Div. 2) {1697} PROGRAMMING 103835
773 Equal Reversal constructive algorithms graphs math Statement F Codeforces Round 803 (Div. 2) {1698} PROGRAMMING 2500.0 Codeforces Round #803 (Div. 2) Editorial
9575 Equate Multisets constructive algorithms data structures graph matchings greedy math number theory Statement F Codeforces Round 805 (Div. 3) {1702} PROGRAMMING 104763
163 Mio and Lucky Array constructive algorithms fft math strings Statement G CodeTON Round 2 (Div. 1 + Div. 2, Rated, Prizes!) {1704} PROGRAMMING 3500.0 CodeTON Round 2 Editorial
22799 Optimal Reduction constructive algorithms sortings Statement B Codeforces Round 812 (Div. 2) {1713} PROGRAMMING 1000.0 Codeforces Round #812 (Div. 2) Editorial 1000
8323 Letter Picking constructive algorithms dp games Statement D Educational Codeforces Round 135 (Rated for Div. 2) {1728} PROGRAMMING 106805
21740 Jumping on Tiles constructive algorithms strings Statement C Codeforces Round 820 (Div. 3) {1729} PROGRAMMING Codeforces Round #820 (Div. 3) Editorial
3067 Prefixes and Suffixes constructive algorithms dsu strings Statement D Codeforces Round 823 (Div. 2) {1730} PROGRAMMING 2250.0 Codeforces Round #823 — editorial 2200
2805 Equal Binary Subsequences constructive algorithms greedy strings Statement D Codeforces Round 825 (Div. 2) {1736} PROGRAMMING 2000.0 Codeforces Round #825 (Div. 2) Editorial
577 Anti-Increasing Addicts constructive algorithms dfs and similar dp greedy Statement G Codeforces Global Round 22 {1738} PROGRAMMING 3000.0 Editorial of Codeforces Global Round <strong>22</strong>
19044 Prefix Sum Addicts constructive algorithms math sortings Statement B Codeforces Global Round 22 {1738} PROGRAMMING 1000.0 Editorial of Codeforces Global Round <strong>22</strong>
14247 Smaller constructive algorithms greedy strings Statement F Codeforces Round 827 (Div. 4) {1742} PROGRAMMING 107962
10530 Complementary XOR constructive algorithms data structures Statement C CodeTON Round 3 (Div. 1 + Div. 2, Rated, Prizes!) {1750} PROGRAMMING 1250.0 CodeTON Round 3 (Div. 1 + Div. 2) Editorial
125 BinaryStringForces constructive algorithms data structures Statement H CodeTON Round 3 (Div. 1 + Div. 2, Rated, Prizes!) {1750} PROGRAMMING 3500.0 CodeTON Round 3 (Div. 1 + Div. 2) Editorial
17868 Indirect Sort constructive algorithms math Statement A CodeTON Round 3 (Div. 1 + Div. 2, Rated, Prizes!) {1750} PROGRAMMING 500.0 CodeTON Round 3 (Div. 1 + Div. 2) Editorial
27157 SSeeeeiinngg DDoouubbllee constructive algorithms strings Statement A Codeforces Round 836 (Div. 2) {1758} PROGRAMMING 500.0 Codeforces Round #836 (Div. 2) Editorial
154 Unequal Adjacent Elements constructive algorithms sortings Statement G Codeforces Round 838 (Div. 2) {1762} PROGRAMMING 3500.0 Codeforces Round #838 (Div. 2) Editorial
15834 Elemental Decompress constructive algorithms greedy implementation sortings Statement C Codeforces Round 842 (Div. 2) {1768} PROGRAMMING 1500.0 Codeforces Round #842 (Div. 2) Editorial
20038 Gardener and the Capybaras (hard version) constructive algorithms greedy strings Statement A2 Codeforces Round 843 (Div. 2) {1775} PROGRAMMING 500.0 Codeforces Round #843 (Div. 2) Editorial
2411 Another Wine Tasting Event combinatorics constructive algorithms strings Statement G SWERC 2022-2023 - Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1776} PROGRAMMING
24128 Hall of Fame constructive algorithms greedy math strings Statement A Hello 2023 {1779} PROGRAMMING 500.0
19615 Matching Numbers constructive algorithms greedy math Statement C Codeforces Round 851 (Div. 2) {1788} PROGRAMMING 1500.0 Codeforces Round #851 (Div. 2) Editorial
1963 Serval and Shift-Shift-Shift bitmasks brute force constructive algorithms implementation Statement D Codeforces Round 853 (Div. 2) {1789} PROGRAMMING 1750.0 Codeforces Round #853 (Div. 2) Editorial
19058 Prefix and Suffix Array constructive algorithms strings Statement A Codeforces Round 856 (Div. 2) {1794} PROGRAMMING 750.0 Codeforces Round 856 (Div. 2) Editorial
26019 Li Hua and Pattern constructive algorithms greedy Statement B Codeforces Round 864 (Div. 2) {1797} PROGRAMMING 1000.0 Codeforces Round 864 (Div. 2) Editorial
7020 Double Lexicographically Minimum constructive algorithms greedy implementation strings Statement C Codeforces Round 854 by cybercats (Div. 1 + Div. 2) {1799} PROGRAMMING 1500.0 Codeforces Round #854 Editorial
8761 Umka and a Long Flight constructive algorithms implementation math Statement D Codeforces Round 863 (Div. 3) {1811} PROGRAMMING 114788
4354 Unique Palindromes binary search constructive algorithms greedy math strings Statement D Codeforces Round 868 (Div. 2) {1823} PROGRAMMING 2000.0 115465
946 Bus Routes binary search constructive algorithms dfs and similar greedy trees Statement E Codeforces Round 873 (Div. 1) {1827} PROGRAMMING 2500.0 Codeforces Round #873 (Div. 1 & 2) Editorial 3400
24848 Best Binary String constructive algorithms greedy Statement C Educational Codeforces Round 149 (Rated for Div. 2) {1837} PROGRAMMING 116752
3751 Bracket Walk constructive algorithms data structures implementation sortings strings Statement D Codeforces Round 877 (Div. 2) {1838} PROGRAMMING 1750.0 Codeforces Round #877 (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
13946 Row Major constructive algorithms math number theory strings Statement D Codeforces Round 884 (Div. 1 + Div. 2) {1844} PROGRAMMING 1500.0 Codeforces Round #884 (Div. 1 + Div. 2) Editorial
27760 Good Arrays constructive algorithms implementation math Statement B Codeforces Round 890 (Div. 2) supported by Constructor Institute {1856} PROGRAMMING 750.0 Codeforces Round #890 (Div. 2) Editorial
23744 Not a Substring constructive algorithms dp strings Statement A Educational Codeforces Round 153 (Rated for Div. 2) {1860} PROGRAMMING Educational Codeforces Round 153 Editorial
24243 Two Binary Strings constructive algorithms dfs and similar greedy Statement B Educational Codeforces Round 154 (Rated for Div. 2) {1861} PROGRAMMING Educational Codeforces Round 154 Editorial
3111 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
18773 XOR Palindromes bitmasks constructive algorithms strings Statement B Codeforces Round 897 (Div. 2) {1867} PROGRAMMING 1000.0
6941 Cyclic Operations constructive algorithms dfs and similar graphs greedy implementation Statement D Codeforces Round 897 (Div. 2) {1867} PROGRAMMING 2000.0
2802 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
8420 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
17307 Decreasing String constructive algorithms strings Statement C Educational Codeforces Round 156 (Rated for Div. 2) {1886} PROGRAMMING Educational Codeforces Round 156 Editorial
15489 Qingshan Loves Strings 2 constructive algorithms greedy Statement A Codeforces Round 906 (Div. 1) {1889} PROGRAMMING 750.0 Codeforces Round 906 Editorial
11810 Matching Arrays binary search constructive algorithms greedy sortings Statement C CodeTON Round 7 (Div. 1 + Div. 2, Rated, Prizes!) {1896} PROGRAMMING 1500.0 CodeTON Round 7 (Div. 1 + Div. 2, Rated, Prizes!) Editorial
15024 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
5826 Set To Max (Hard Version) binary search constructive algorithms data structures dsu greedy implementation sortings two pointers Statement D2 Codeforces Round 914 (Div. 2) {1904} PROGRAMMING 750.0 Codeforces Round 914 (Div. 2) Editorial
8791 Set To Max (Easy Version) brute force constructive algorithms greedy Statement D1 Codeforces Round 914 (Div. 2) {1904} PROGRAMMING 1250.0 Codeforces Round 914 (Div. 2) Editorial
23435 Removal of Unattractive Pairs constructive algorithms greedy math strings Statement C Codeforces Round 913 (Div. 3) {1907} PROGRAMMING Codeforces Round 913 (Div. 3) Editorial
9865 Mathematical Problem brute force constructive algorithms implementation math strings Statement D Good Bye 2023 {1916} PROGRAMMING 1500.0
28466 2023 constructive algorithms implementation math number theory Statement A Good Bye 2023 {1916} PROGRAMMING 250.0
29004 Tricky Template constructive algorithms implementation strings Statement A Educational Codeforces Round 161 (Rated for Div. 2) {1922} PROGRAMMING Educational Codeforces Round 161 Editorial
18735 Find B constructive algorithms data structures greedy Statement C Educational Codeforces Round 162 (Rated for Div. 2) {1923} PROGRAMMING Educational Codeforces Round 162 Editorial
16997 Did We Get Everything Covered? constructive algorithms dp greedy strings Statement A Codeforces Round 921 (Div. 1) {1924} PROGRAMMING 500.0 Codeforces Round 921 (Div. 1, Div. 2) Editorial
31319 We Got Everything Covered! constructive algorithms greedy strings Statement A Codeforces Round 921 (Div. 2) {1925} PROGRAMMING 500.0 Codeforces Round 921 (Div. 1, Div. 2) Editorial
38575 Following the String constructive algorithms greedy strings Statement B Codeforces Round 923 (Div. 3) {1927} PROGRAMMING 125597
2221 Modular Sequence constructive algorithms dp greedy implementation math number theory Statement E Codeforces Round 924 (Div. 2) {1928} PROGRAMMING 2250.0 Codeforces Round 924 Editorial
24548 Rectangle Cutting constructive algorithms geometry greedy math Statement A Codeforces Round 924 (Div. 2) {1928} PROGRAMMING 500.0 Codeforces Round 924 Editorial
23869 Turtle Tenacity: Continual Mods constructive algorithms greedy number theory sortings Statement D Codeforces Round 929 (Div. 3) {1933} PROGRAMMING Codeforces Round 929 (Div. 3) Editorial
30504 Entertainment in MAC constructive algorithms strings Statement A Codeforces Round 932 (Div. 2) {1935} PROGRAMMING 500.0 Codeforces Round #932 (Div. 2) Editorial
4582 No Palindromes brute force constructive algorithms greedy hashing implementation strings Statement E Codeforces Global Round 25 {1951} PROGRAMMING 2250.0 Codeforces Global Round 25 Editorial
32727 Progressive Square constructive algorithms data structures implementation sortings Statement B Codeforces Round 938 (Div. 3) {1955} PROGRAMMING 128243
2457 Folding Strip constructive algorithms greedy strings Statement C Codeforces Round 941 (Div. 1) {1965} PROGRAMMING 1500.0 Codeforces Round #941 (Div. 1, Div. 2) Editorial 2300
17426 Rectangle Filling constructive algorithms implementation Statement B Codeforces Round 941 (Div. 2) {1966} PROGRAMMING 1000.0 Codeforces Round #941 (Div. 1, Div. 2) Editorial 1100
22554 Shifts and Sorting constructive algorithms greedy Statement B Educational Codeforces Round 165 (Rated for Div. 2) {1969} PROGRAMMING Educational Codeforces Round 165 Editorial 1000
966 Arithmancy (Easy) brute force constructive algorithms interactive strings Statement D1 Helvetic Coding Contest 2024 online mirror (teams allowed, unrated) {1970} PROGRAMMING Helvetic Coding Contest 2024 Editorial 2100
330 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
18001 Manhattan Permutations constructive algorithms greedy implementation math Statement C Codeforces Round 953 (Div. 2) {1978} PROGRAMMING 1250.0 130527
7950 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
13218 Permutation of Rows and Columns constructive algorithms data structures hashing math matrices sortings Statement E Codeforces Round 950 (Div. 3) {1980} PROGRAMMING 130135
11453 Swap Dilemma constructive algorithms divide and conquer greedy math sortings Statement D Codeforces Round 956 (Div. 2) and ByteRace 2024 {1983} PROGRAMMING 1750.0
18583 Corner Twist constructive algorithms greedy implementation math Statement B Codeforces Round 956 (Div. 2) and ByteRace 2024 {1983} PROGRAMMING 1000.0
21192 Large Addition constructive algorithms implementation math Statement B Codeforces Global Round 26 {1984} PROGRAMMING 750.0 Codeforces Global Round 26 Editorial
10962 Novice's Mistake brute force constructive algorithms math strings Statement E Codeforces Round 957 (Div. 3) {1992} PROGRAMMING Shayan's Video Tutorial
19820 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
1610 Stardew Valley constructive algorithms dfs and similar graphs Statement F Codeforces Round 959 sponsored by NEAR (Div. 1 + Div. 2) {1994} PROGRAMMING 2500.0 Video Tutorial
7690 Funny Game constructive algorithms dsu graphs greedy math number theory Statement D Codeforces Round 959 sponsored by NEAR (Div. 1 + Div. 2) {1994} PROGRAMMING 2000.0 Video Tutorial
17959 Black Circles brute force constructive algorithms geometry greedy math Statement C EPIC Institute of Technology Round August 2024 (Div. 1 + Div. 2) {2002} PROGRAMMING 1000.0 EPIC Institute of Technology Round August 2024 (Div. 1 + Div. 2) Editorial
21929 Turtle and Good Pairs constructive algorithms greedy strings Statement C Codeforces Round 968 (Div. 2) {2003} PROGRAMMING 1000.0 sol-zh.pdf
42256 Sakurako's Exam brute force constructive algorithms greedy math Statement A Codeforces Round 970 (Div. 3) {2008} PROGRAMMING Codeforces Round 970 (Div. 3) Editorial
14826 Password Cracking brute force constructive algorithms interactive strings Statement C Codeforces Round 973 (Div. 2) {2013} PROGRAMMING 1250.0 134298
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
865 Palindrome Everywhere constructive algorithms greedy Statement F Refact.ai Match 1 (Codeforces Round 985) {2029} PROGRAMMING 3000.0 Refact.ai Match 1 (Codeforces Round 985) Editorial
2048 Permutations Harmony brute force combinatorics constructive algorithms greedy hashing implementation math Statement E Rayan Programming Contest 2024 - Selection (Codeforces Round 989, Div. 1 + Div. 2) {2034} PROGRAMMING 2000.0 Rayan 2024 Selection Round Editorial
17569 Shohag Loves Strings constructive algorithms greedy implementation strings Statement B CodeTON Round 9 (Div. 1 + Div. 2, Rated, Prizes!) {2039} PROGRAMMING 1000.0 Editorial of CodeTON Round 9 (Div. 1 + Div. 2)
3572 Kevin and Bipartite Graph constructive algorithms graphs greedy Statement E Codeforces Global Round 28 {2048} PROGRAMMING 1750.0 Tutorial
19192 pspspsps brute force constructive algorithms implementation Statement B Codeforces Round 994 (Div. 2) {2049} PROGRAMMING 750.0 Codeforces Round #994 (Div. 2) Editorial
33922 Two Frogs constructive algorithms games greedy Statement A Codeforces Round 996 (Div. 2) {2055} PROGRAMMING 500.0 Codeforces Round 996 (Div. 2) Editorial
56704 Skibidus and Amog'u brute force constructive algorithms implementation strings Statement A Codeforces Round 1003 (Div. 4) {2065} PROGRAMMING Video Tutorial
12274 Skibidus and Rizz constructive algorithms greedy Statement E Codeforces Round 1003 (Div. 4) {2065} PROGRAMMING Video Tutorial
1949 A, B, AB and BA constructive algorithms greedy sortings strings Statement E Educational Codeforces Round 174 (Rated for Div. 2) {2069} PROGRAMMING 139774
31397 Having Been a Treasurer in the Past, I Help Goblins Deceive combinatorics constructive algorithms strings Statement B Codeforces Round 1006 (Div. 3) {2072} PROGRAMMING Codeforces Round 1006 (Div. 3) Editorial
23859 Serval and String Theory constructive algorithms implementation Statement A Codeforces Round 1011 (Div. 2) {2085} PROGRAMMING 500.0 Codeforces Round #1011 (Div. 2) Editorial
6988 Mishkin Energizer brute force constructive algorithms greedy implementation strings Statement D Codeforces Round 1014 (Div. 2) {2092} PROGRAMMING 1750.0 Codeforces Round #1014 (Div. 2) Editorial
437 Andryusha and CCB brute force constructive algorithms greedy math number theory strings Statement F Codeforces Round 1014 (Div. 2) {2092} PROGRAMMING 3000.0 Codeforces Round #1014 (Div. 2) Editorial
21892 Dinner Time constructive algorithms math Statement A Codeforces Round 1024 (Div. 2) {2102} PROGRAMMING 250.0 142788
32811 Above the Clouds constructive algorithms greedy strings Statement B Codeforces Round 1032 (Div. 3) {2121} PROGRAMMING Codeforces Round 1032 (Div. 3) Editorial
20248 Greedy Grid constructive algorithms greedy Statement A Order Capital Round 1 (Codeforces Round 1038, Div. 1 + Div. 2) {2122} PROGRAMMING 500.0 Order Capital Round 1 (Codeforces Round 1038, Div. 1 + Div. 2) Editorial
22451 Binary String Battle constructive algorithms games greedy Statement D Codeforces Round 1034 (Div. 3) {2123} PROGRAMMING Codeforces Round 1034 (Div. 3) Editorial
20116 Deranged Deletions constructive algorithms sortings Statement A EPIC Institute of Technology Round Summer 2025 (Codeforces Round 1036, Div. 1 + Div. 2) {2124} PROGRAMMING 500.0 EPIC Institute of Technology Round Summer 2025 (Codeforces Round 1036, Div. 1 + Div. 2) Editorial
28459 Difficult Contest constructive algorithms implementation sortings strings Statement A Educational Codeforces Round 181 (Rated for Div. 2) {2125} PROGRAMMING Educational Codeforces Round 181 Editorial
20623 Mix Mex Max constructive algorithms greedy math Statement A Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) {2127} PROGRAMMING 500.0 Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) Editorial
1787 Interactive RBS (Hard Version) binary search bitmasks constructive algorithms dp interactive Statement C3 Codeforces Round 1040 (Div. 1) {2129} PROGRAMMING 750.0 Codeforces Round 1040 (Div. 1, Div. 2) Editorial
4214 Interactive RBS (Easy Version) binary search bitmasks constructive algorithms interactive Statement C1 Codeforces Round 1040 (Div. 1) {2129} PROGRAMMING 750.0 Codeforces Round 1040 (Div. 1, Div. 2) Editorial
2857 Interactive RBS (Medium Version) binary search bitmasks constructive algorithms interactive Statement C2 Codeforces Round 1040 (Div. 1) {2129} PROGRAMMING 750.0 Codeforces Round 1040 (Div. 1, Div. 2) Editorial
27343 Painting With Two Colors constructive algorithms implementation math Statement A Codeforces Round 1045 (Div. 2) {2134} PROGRAMMING 500.0 145832
2107 Make Good constructive algorithms math strings Statement E Codeforces Round 1051 (Div. 2) {2143} PROGRAMMING 2500.0 Codeforces Round 1051 (Div. 2) Editorial
1082 Bracket Groups constructive algorithms dp strings Statement F Educational Codeforces Round 182 (Rated for Div. 2) {2144} PROGRAMMING Educational Codeforces Round 182 Editorial
17698 Abraham's Great Escape constructive algorithms graphs Statement B Codeforces Round 1056 (Div. 2) {2155} PROGRAMMING 1000.0 Codeforces Round 1056 (Div. 2) Editorial
3419 Palindrome Flipping brute force constructive algorithms implementation strings Statement D Codeforces Round 1067 (Div. 2) {2158} PROGRAMMING 2000.0 Codeforces Round 1067 (Div. 2) Editorial
7549 Rae Taylor and Trees (hard version) binary search constructive algorithms data structures dp dsu implementation trees Statement F Codeforces Round 1065 (Div. 3) {2171} PROGRAMMING Codeforces Round 1065 (Div. 3) Editorial
6005 Blackslex and Girls constructive algorithms geometry math Statement E Codeforces Round 1071 (Div. 3) {2179} PROGRAMMING Codeforces Round 1071 (Div. 3) Editorial
11391 Sub-RBS (Easy Version) combinatorics constructive algorithms dp greedy strings two pointers Statement B1 Codeforces Round 1073 (Div. 1) {2190} PROGRAMMING 750.0 Codeforces Round 1073 (Div. 1, Div. 2) Editorial
20802 MEX Reordering constructive algorithms sortings Statement B Codeforces Round 1073 (Div. 2) {2191} PROGRAMMING 1000.0 Codeforces Round 1073 (Div. 1, Div. 2) Editorial
2263 Swap to Rearrange constructive algorithms dfs and similar graph matchings graphs greedy strings Statement E Codeforces Round 1081 (Div. 2) {2192} PROGRAMMING 2250.0 Codeforces Round 1081 (Div. 2) Editorial
15743 Flipping Binary String constructive algorithms strings Statement B Codeforces Round 1081 (Div. 2) {2192} PROGRAMMING 1000.0 Codeforces Round 1081 (Div. 2) Editorial
1798 N-MEX (Constructive Version) constructive algorithms greedy Statement E1 Codeforces Round 1085 (Div. 1 + Div. 2) {2207} PROGRAMMING 1750.0 Codeforces Round 1085 (Div. 1 + Div. 2) Editorial
21766 Bingo Candies constructive algorithms math Statement A Codeforces Round 1086 (Div. 2) {2208} PROGRAMMING 500.0 Tutorial
361 Binary Strings are Simple? constructive algorithms dsu interactive number theory Statement E Codeforces Round 1089 (Div. 2) {2210} PROGRAMMING 2750.0 Codeforces Round 1089 (Div. 2) Editorial
2248 A Simple RBS Problem constructive algorithms strings trees Statement D Codeforces Round 1089 (Div. 2) {2210} PROGRAMMING 2250.0 Codeforces Round 1089 (Div. 2) Editorial
7617 Zhily and Bracket Swapping constructive algorithms greedy Statement A Codeforces Round 1097 (Div. 1, Based on Zhili Cup 2026) {2223} PROGRAMMING 500.0 Codeforces Round 1097 (Div. 1, Div2, Based on Zhili Cup 2026) Tutorial
3103 Reserved Reversals constructive algorithms dp greedy Statement D Codeforces Round 1095 (Div. 2) {2226} PROGRAMMING 2000.0 Codeforces Round 1095 (Div. 2) Editorial
13628 Palindromex binary search brute force constructive algorithms data structures greedy implementation two pointers Statement D Codeforces Round 1096 (Div. 3) {2227} PROGRAMMING Codeforces Round 1096 (Div. 3) — Editorial