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Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 1644 | Axis Walking | bitmasks combinatorics constructive algorithms dp meet-in-the-middle | Statement | E | Codeforces Round 191 (Div. 2) {327} | PROGRAMMING | Codeforces Round #191 — Tutorial | 2500 | |
| 1157 | Bags and Coins | bitmasks constructive algorithms dp greedy | Statement | D | Codeforces Round 207 (Div. 1) {356} | PROGRAMMING | 9210 | 2500 | |
| 2616 | Fox and Minimal path | bitmasks constructive algorithms graphs implementation math | Statement | B | Codeforces Round 228 (Div. 1) {388} | PROGRAMMING | Codeforces Round #228 — Editorial | 2000 | |
| 1064 | Guess the Tree | bitmasks constructive algorithms dp greedy trees | Statement | C | Codeforces Round 245 (Div. 1) {429} | PROGRAMMING | Codeforces Round #245 — Editorial | 2400 | |
| 43996 | Fedor and New Game | bitmasks brute force constructive algorithms implementation | Statement | B | Codeforces Round 267 (Div. 2) {467} | PROGRAMMING | Разбор задач | 1200 | |
| 13839 | Bits | bitmasks constructive algorithms | Statement | A | Codeforces Round 276 (Div. 1) {484} | PROGRAMMING | Codeforces Round #276 — Editorial | 1700 | |
| 729 | Restoring Map | bitmasks constructive algorithms trees | Statement | E | VK Cup 2015 - Finals, online mirror {566} | PROGRAMMING | Editorial for VK Cup 2015 — Finals | 3200 | |
| 9491 | Tree Requests | binary search bitmasks constructive algorithms dfs and similar graphs trees | Statement | D | Codeforces Round 316 (Div. 2) {570} | PROGRAMMING | Codeforces Round #316 Editorial | 2400 | |
| 5001 | Three Logos | bitmasks brute force constructive algorithms geometry implementation math | Statement | D | Codeforces Round 322 (Div. 2) {581} | PROGRAMMING | Codeforces Round #322 (Div.2) Editorial | 1700 | |
| 1455 | Anton and School | bitmasks constructive algorithms implementation math | Statement | F | Codeforces Round 379 (Div. 2) {734} | PROGRAMMING | Tutorial of Codeforces Round #379 (Div. 2) | 2600 | |
| 16196 | Chloe and the sequence | binary search bitmasks constructive algorithms implementation | Statement | B | Codeforces Round 384 (Div. 2) {743} | PROGRAMMING | Codeforces Round #384 Editorial | 1200 | |
| 3645 | 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 | |
| 5071 | Qualification Rounds | bitmasks brute force constructive algorithms dp | Statement | C | Codeforces Round 438 by Sberbank and Barcelona Bootcamp (Div. 1 + Div. 2 combined) {868} | PROGRAMMING | 55046 | 1500 | |
| 6065 | Short Program | bitmasks constructive algorithms | Statement | A | Codeforces Round 443 (Div. 1) {878} | PROGRAMMING | Editorial | 1600 | |
| 6204 | Xor-MST | bitmasks constructive algorithms data structures | Statement | G | Educational Codeforces Round 32 {888} | PROGRAMMING | Educational Codeforces Round 32 - Editorial | 2300 | |
| 14298 | New Year's Eve | bitmasks constructive algorithms number theory | Statement | B | Codeforces Round 456 (Div. 2) {912} | PROGRAMMING | Codeforces Round #456 (Div. 2) Editorial | 1400 | |
| 4197 | 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 | |
| 3247 | Ehab and another another xor problem | bitmasks constructive algorithms implementation interactive | Statement | D | Codeforces Round 525 (Div. 2) {1088} | PROGRAMMING | Codeforces round #525 editorial | 2000 | |
| 1672 | Decypher the String | bitmasks chinese remainder theorem constructive algorithms interactive math | Statement | E | Educational Codeforces Round 60 (Rated for Div. 2) {1117} | PROGRAMMING | 65365 | 2200 | |
| 1192 | Foo Fighters | bitmasks constructive algorithms | Statement | F | Codeforces Global Round 3 {1148} | PROGRAMMING | Codeforces Global Round 3 Editorial | 2500 | |
| 13194 | Dima and a Bad XOR | bitmasks brute force constructive algorithms dp | Statement | B | Codeforces Round 553 (Div. 2) {1151} | PROGRAMMING | Codeforces Round #553 (Div. 2) Editorial | 1600 | |
| 9478 | Neko Performs Cat Furrier Transform | bitmasks constructive algorithms dfs and similar math | Statement | B | Codeforces Round 554 (Div. 2) {1152} | PROGRAMMING | T | 1300 | |
| 1056 | Magical Permutation | bitmasks brute force constructive algorithms data structures graphs math | Statement | E | Codeforces Round 558 (Div. 2) {1163} | PROGRAMMING | 66943 | 2800 | |
| 3046 | The LCMs Must be Large | bitmasks brute force constructive algorithms math number theory | Statement | E | Codeforces Round 561 (Div. 2) {1166} | PROGRAMMING | Codeforces Round #561 (Div. 2) Editorial | 2000 | |
| 5132 | Ehab and the Expected XOR Problem | bitmasks constructive algorithms | Statement | D | Codeforces Round 563 (Div. 2) {1174} | PROGRAMMING | Codeforces round #563 editorial | 1900 | |
| 680 | To Make 1 | bitmasks constructive algorithms dp greedy number theory | Statement | G | Technocup 2020 - Elimination Round 2 {1225} | PROGRAMMING | 70898 | 3000 | |
| 15223 | Make Good | bitmasks constructive algorithms math | Statement | C | Good Bye 2019 {1270} | PROGRAMMING | Разбор Goodbye 2019 | 1500 | |
| 4733 | Present | binary search bitmasks constructive algorithms data structures math sortings | Statement | B | Codeforces Round 626 (Div. 1, based on Moscow Open Olympiad in Informatics) {1322} | PROGRAMMING | 1000.0 | Codeforces Round #626 Editorial | |
| 13904 | Ehab the Xorcist | bitmasks constructive algorithms greedy number theory | Statement | D | Codeforces Round 628 (Div. 2) {1325} | PROGRAMMING | 1750.0 | 74235 | 1700 |
| 8519 | Walk on Matrix | bitmasks constructive algorithms math | Statement | D | Codeforces Round 630 (Div. 2) {1332} | PROGRAMMING | 1250.0 | Codeforces Round #630 Editorial | 1700 |
| 3499 | 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 | |
| 9749 | Edge Weight Assignment | bitmasks constructive algorithms greedy math trees | Statement | B | Codeforces Round 633 (Div. 1) {1338} | PROGRAMMING | 1000.0 | Editorial | |
| 9413 | 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 |
| 13750 | 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 | |
| 4939 | Binary Median | bitmasks brute force constructive algorithms | Statement | H | Codeforces Round 644 (Div. 3) {1360} | PROGRAMMING | Codeforces Round #644 (Div. 3) Editorial | 2100 | |
| 2165 | Johnny and Megan's Necklace | binary search bitmasks constructive algorithms dfs and similar dsu graphs | Statement | C | Codeforces Round 647 (Div. 1) - Thanks, Algo Muse! {1361} | PROGRAMMING | 2000.0 | Codeforces Round #647 Editorial | 2500 |
| 1694 | X-OR | bitmasks constructive algorithms interactive probabilities | Statement | E | Codeforces Round 649 (Div. 2) {1364} | PROGRAMMING | 2500.0 | Codeforces round #649 editorial | 2700 |
| 1565 | Secure Password | bitmasks combinatorics constructive algorithms interactive math | Statement | G | Codeforces Round 648 (Div. 2) {1365} | PROGRAMMING | 3000.0 | Editorial — Codeforces Round #648 | 2800 |
| 5609 | GameGame | bitmasks constructive algorithms dp games greedy math | Statement | B | Codeforces Round 659 (Div. 1) {1383} | PROGRAMMING | 1000.0 | Codeforces Round #659 Editorial | |
| 3951 | Omkar and Duck | bitmasks constructive algorithms interactive math | Statement | E | Codeforces Global Round 10 {1392} | PROGRAMMING | 2000.0 | Codeforces Global Round 10 — Editorial | |
| 2790 | Two Different | bitmasks constructive algorithms divide and conquer greedy | Statement | F | Grakn Forces 2020 {1408} | PROGRAMMING | 2500.0 | Grakn Forces -- Editorial | |
| 6284 | XOR-gun | bitmasks brute force constructive algorithms | Statement | D | Technocup 2021 - Elimination Round 2 {1415} | PROGRAMMING | 2000.0 | Editorial of Codeforces Round 687 (Technocup 2021 — Elimitation Round 2) | |
| 3557 | Decryption | bitmasks constructive algorithms implementation math number theory | Statement | E | Codeforces Round 671 (Div. 2) {1419} | PROGRAMMING | 2250.0 | Codeforces Round #671 Editorial | |
| 1728 | Xum | bitmasks constructive algorithms math number theory | Statement | E | Codeforces Global Round 11 {1427} | PROGRAMMING | 1500.0 | Editorial of Global Round 11 | 2500 |
| 4669 | Powerful Ksenia | bitmasks constructive algorithms | Statement | D | Codeforces Round 682 (Div. 2) {1438} | PROGRAMMING | 1750.0 | Codeforces Round #682 (Div. 2) Editorial | |
| 5610 | Bitwise Queries (Easy Version) | bitmasks constructive algorithms interactive math | Statement | E1 | Codeforces Round 685 (Div. 2) {1451} | PROGRAMMING | 1500.0 | Editorial — Codeforces Round #685 | |
| 3986 | Bitwise Queries (Hard Version) | bitmasks constructive algorithms interactive math | Statement | E2 | Codeforces Round 685 (Div. 2) {1451} | PROGRAMMING | 1000.0 | Editorial — Codeforces Round #685 | |
| 1482 | Continuous City | bitmasks constructive algorithms | Statement | C | Codeforces Round 700 (Div. 1) {1479} | PROGRAMMING | 1500.0 | Editorial of Codeforces Round #700 | |
| 8573 | Zookeeper and The Infinite Zoo | bitmasks constructive algorithms math | Statement | D | Codeforces Global Round 13 {1491} | PROGRAMMING | 1250.0 | Codeforces Global Round 13 Editorial | |
| 6561 | Genius's Gambit | bitmasks constructive algorithms math | Statement | D | Codeforces Round 704 (Div. 2) {1492} | PROGRAMMING | 2250.0 | Codeforces Round #704 Editorial | |
| 986 | 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 |
| 4511 | Almost Sorted | binary search bitmasks combinatorics constructive algorithms dp implementation math | Statement | B | Codeforces Round 715 (Div. 1) {1508} | PROGRAMMING | 1000.0 | Codeforces Round #715 Editorial | |
| 21313 | AND Sequences | bitmasks combinatorics constructive algorithms | Statement | B | Divide by Zero 2021 and Codeforces Round 714 (Div. 2) {1513} | PROGRAMMING | 1250.0 | Divide by Zero 2021 and Codeforces Round #714 (Div. 2) Editorial | |
| 14569 | Baby Ehab Partitions Again | bitmasks constructive algorithms dp math | Statement | C | Codeforces Round 717 (Div. 2) {1516} | PROGRAMMING | 1500.0 | Codeforces round #717 editorial | |
| 8072 | RPD and Rap Sheet (Easy Version) | bitmasks constructive algorithms interactive math | Statement | D1 | Codeforces Round 730 (Div. 2) {1543} | PROGRAMMING | 1000.0 | Codeforces Round #730 (Div. 2) Editorial | |
| 9072 | Take a Guess | bitmasks constructive algorithms interactive math | Statement | D | Deltix Round, Summer 2021 (open for everyone, rated, Div. 1 + Div. 2) {1556} | PROGRAMMING | 1500.0 | 94384 | 1800 |
| 49191 | Mocha and Math | bitmasks constructive algorithms math | Statement | A | Codeforces Round 738 (Div. 2) {1559} | PROGRAMMING | 500.0 | Tutorial (en) | 900 |
| 6849 | 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 | |
| 5119 | 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 | |
| 21518 | MIN-MEX Cut | bitmasks constructive algorithms dp | Statement | B | Codeforces Global Round 16 {1566} | PROGRAMMING | 750.0 | Codeforces Global Round 16 Editorial | |
| 19252 | MAX-MEX Cut | bitmasks constructive algorithms dp greedy | Statement | C | Codeforces Global Round 16 {1566} | PROGRAMMING | 1000.0 | Codeforces Global Round 16 Editorial | |
| 1643 | Defender of Childhood Dreams | bitmasks constructive algorithms divide and conquer | Statement | F | Technocup 2022 - Elimination Round 1 {1583} | PROGRAMMING | 2750.0 | Editorial for Technocup 2022 — Elimination Round 1 and Codeforces Round #749 (Div. 1+Div. 2) | |
| 9425 | Bakry and Partitioning | bitmasks constructive algorithms dfs and similar dp graphs trees | Statement | C | Codeforces Round 746 (Div. 2) {1592} | PROGRAMMING | 1500.0 | 95583 | |
| 3316 | Treelabeling | bitmasks constructive algorithms dfs and similar games graphs greedy trees | Statement | D | Codeforces Round 754 (Div. 2) {1605} | PROGRAMMING | 2000.0 | tutorial | 2100 |
| 11493 | Divan and bitwise operations | bitmasks combinatorics constructive algorithms dp math | Statement | C | Codeforces Round 757 (Div. 2) {1614} | PROGRAMMING | 1500.0 | Tutorial | 1500 |
| 16349 | And Matching | bitmasks constructive algorithms | Statement | A | Codeforces Round 768 (Div. 1) {1630} | PROGRAMMING | 500.0 | Editorial of Codeforces Round #768 | |
| 33849 | Roof Construction | bitmasks constructive algorithms | Statement | B | Codeforces Round 769 (Div. 2) {1632} | PROGRAMMING | 1000.0 | Editorial of Codeforces Round #769 | |
| 20845 | Factorials and Powers of Two | bitmasks brute force constructive algorithms math | Statement | C | Codeforces Round 774 (Div. 2) {1646} | PROGRAMMING | 1250.0 | Codeforces Round #774 (Div. 2) Editorial | 1500 |
| 12128 | Bit Flipping | bitmasks constructive algorithms greedy strings | Statement | B | Codeforces Round 782 (Div. 2) {1659} | PROGRAMMING | 750.0 | Codeforces Round #782 (Div. 2) Editorial | |
| 4810 | GCD Guess | bitmasks chinese remainder theorem constructive algorithms interactive math number theory | Statement | D | Codeforces Round 781 (Div. 2) {1665} | PROGRAMMING | 1500.0 | Codeforces Round #781 (Div. 2) Editorial | |
| 2017 | Hemose on the Tree | bitmasks constructive algorithms dfs and similar trees | Statement | E | Codeforces Round 788 (Div. 2) {1670} | PROGRAMMING | 2750.0 | Tutorial | 2200 |
| 1000 | 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 | |
| 28432 | AND Sorting | bitmasks constructive algorithms sortings | Statement | B | Codeforces Round 793 (Div. 2) {1682} | PROGRAMMING | 1000.0 | Codeforces Round #793 (Div. 2) Editorial | |
| 23838 | Cirno's Perfect Bitmasks Classroom | bitmasks brute force constructive algorithms | Statement | A | Codeforces Round 796 (Div. 2) {1688} | PROGRAMMING | 500.0 | Tutorial | |
| 19193 | Patchouli's Magical Talisman | bitmasks constructive algorithms greedy sortings | Statement | B | Codeforces Round 796 (Div. 2) {1688} | PROGRAMMING | 750.0 | Tutorial | |
| 1424 | ANDfinity | bitmasks brute force constructive algorithms dfs and similar dsu graphs | Statement | E | Codeforces Round 798 (Div. 2) {1689} | PROGRAMMING | 2500.0 | Editorial for Codeforces Round #798 (Div. 2) | |
| 1174 | 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 | |
| 22043 | Almost Ternary Matrix | 2-sat bitmasks constructive algorithms matrices | Statement | B | Codeforces Round 804 (Div. 2) {1699} | PROGRAMMING | 1000.0 | Codeforces Round #804 (Div. 2) Editorial | |
| 729 | Mark and the Online Exam | bitmasks constructive algorithms interactive math probabilities | Statement | F | Codeforces Round 807 (Div. 2) {1705} | PROGRAMMING | 3000.0 | Codeforces Round #807 (Div 2.) Editorial | |
| 187 | Bugaboo | bitmasks constructive algorithms dp number theory | Statement | F | Codeforces Round 808 (Div. 1) {1707} | PROGRAMMING | 3250.0 | 104930 | |
| 789 | Lost Array | bitmasks combinatorics constructive algorithms dp math | Statement | F | Codeforces Round 812 (Div. 2) {1713} | PROGRAMMING | 3000.0 | Codeforces Round #812 (Div. 2) Editorial | 2900 |
| 14773 | Even-Odd XOR | bitmasks constructive algorithms greedy | Statement | G | Codeforces Round 817 (Div. 4) {1722} | PROGRAMMING | 106478 | 1500 | |
| 17108 | Mainak and Interesting Sequence | bitmasks constructive algorithms math | Statement | B | Codeforces Round 819 (Div. 1 + Div. 2) and Grimoire of Code Annual Contest 2022 {1726} | PROGRAMMING | 1000.0 | Codeforces Round #819 (Div. 1 + Div. 2) and Grimoire of Code Annual Contest 2022 Editorial | |
| 1844 | Joking (Easy Version) | binary search bitmasks constructive algorithms interactive ternary search | Statement | E1 | Codeforces Global Round 23 {1746} | PROGRAMMING | 2000.0 | Codeforces Global Round 23 Editorial | |
| 5710 | Yet Another Problem | binary search bitmasks constructive algorithms data structures | Statement | D | Codeforces Round 832 (Div. 2) {1747} | PROGRAMMING | 1750.0 | Codeforces Round #832 (Div. 2) Editorial | |
| 3342 | ConstructOR | bitmasks chinese remainder theorem combinatorics constructive algorithms number theory | Statement | D | Codeforces Round 833 (Div. 2) {1748} | PROGRAMMING | 2000.0 | Codeforces Round #833 (Div. 2) Editorial | 2100 |
| 406 | Circular Xor Reversal | bitmasks constructive algorithms | Statement | F | Codeforces Round 833 (Div. 2) {1748} | PROGRAMMING | 2750.0 | Codeforces Round #833 (Div. 2) Editorial | 3000 |
| 10994 | 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 | ||
| 17188 | 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 | |
| 22349 | Gardener and the Array | bitmasks constructive algorithms | Statement | B | Codeforces Round 843 (Div. 2) {1775} | PROGRAMMING | 1000.0 | Codeforces Round #843 (Div. 2) Editorial | |
| 2812 | 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 | |
| 1975 | 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 | |
| 17658 | Vlad and a Pair of Numbers | bitmasks constructive algorithms | Statement | E | Codeforces Round 847 (Div. 3) {1790} | PROGRAMMING | 111948 | ||
| 9917 | The Very Beautiful Blanket | bitmasks constructive algorithms | Statement | A | Codeforces Round 857 (Div. 1) {1801} | PROGRAMMING | 500.0 | Codeforces Round #857 Editorial | |
| 1226 | 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 | |
| 3699 | Balanced String | bitmasks constructive algorithms dp | Statement | D | Educational Codeforces Round 153 (Rated for Div. 2) {1860} | PROGRAMMING | Educational Codeforces Round 153 Editorial | ||
| 3138 | 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 | |
| 15553 | Divisor Chain | bitmasks constructive algorithms math number theory | Statement | C | Harbour.Space Scholarship Contest 2023-2024 (Div. 1 + Div. 2) {1864} | PROGRAMMING | 1250.0 | Harbour.Space Scholarship Contest 2023-2024 (Div. 1 + Div. 2) Editorial | |
| 18852 | XOR Palindromes | bitmasks constructive algorithms strings | Statement | B | Codeforces Round 897 (Div. 2) {1867} | PROGRAMMING | 1000.0 | ||
| 2817 | 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 | |
| 8469 | 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 | |
| 17641 | 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 | |
| 7279 | XOR Construction | bitmasks constructive algorithms data structures math trees | Statement | D | Educational Codeforces Round 157 (Rated for Div. 2) {1895} | PROGRAMMING | Educational Codeforces Round 157 Editorial | ||
| 15121 | 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 | |
| 893 | Button Pressing | bitmasks constructive algorithms hashing | Statement | B | 2023-2024 ICPC, Asia Jakarta Regional Contest (Online Mirror, Unrated, ICPC Rules, Teams Preferred) {1906} | PROGRAMMING | problem_analysis.pdf | ||
| 1278 | Construct Tree | bitmasks constructive algorithms dp trees | Statement | F | Codeforces Round 917 (Div. 2) {1917} | PROGRAMMING | 3000.0 | Editorial of Codeforces Round 917 (Div. 2) | |
| 9336 | Increasing Subsequences | bitmasks constructive algorithms math | Statement | E | Educational Codeforces Round 161 (Rated for Div. 2) {1922} | PROGRAMMING | Educational Codeforces Round 161 Editorial | ||
| 2162 | Vlad and Avoiding X | bitmasks brute force constructive algorithms dfs and similar dp implementation | Statement | F | Codeforces Round 928 (Div. 4) {1926} | PROGRAMMING | 126132 | ||
| 4267 | XOR Break --- Solo Version | bitmasks constructive algorithms greedy | Statement | D1 | Codeforces Round 931 (Div. 2) {1934} | PROGRAMMING | 1500.0 | Tutorial | |
| 8792 | 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 | |
| 18430 | Equal XOR | bitmasks constructive algorithms | Statement | B | Codeforces Round 934 (Div. 2) {1944} | PROGRAMMING | 1000.0 | Codeforces Round #934 (Div1, Div2) Editorial | |
| 5719 | 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 | |
| 1573 | The Most Reckless Defense | bitmasks brute force constructive algorithms dp flows graph matchings | Statement | H | Codeforces Round 938 (Div. 3) {1955} | PROGRAMMING | 128243 | ||
| 4888 | 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) | |
| 20812 | 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 |
| 8331 | 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 |
| 20171 | Binary Colouring | bitmasks constructive algorithms greedy math | Statement | B | Codeforces Round 948 (Div. 2) {1977} | PROGRAMMING | 1250.0 | 129858 | 1100 |
| 8001 | 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 | |
| 6470 | 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 | |
| 20701 | 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) | |
| 8079 | 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 | |
| 19265 | AND Reconstruction | bitmasks constructive algorithms greedy | Statement | B | Pinely Round 4 (Div. 1 + Div. 2) {1991} | PROGRAMMING | 500.0 | Video Tutorial | |
| 19916 | 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 | |
| 11849 | Alya and Permutation | bitmasks constructive algorithms data structures | Statement | C | Codeforces Global Round 27 {2035} | PROGRAMMING | 1000.0 | Codeforces Global Round 27 Editorial | |
| 1868 | Library of Magic | binary search bitmasks constructive algorithms interactive | Statement | G | Codeforces Round 984 (Div. 3) {2036} | PROGRAMMING | Codeforces Round 984 (Div. 3) Editorial | ||
| 14207 | Trip to the Olympiad | bitmasks constructive algorithms greedy math | Statement | C | Hello 2025 {2057} | PROGRAMMING | 1500.0 | ||
| 1135 | Infinite Sequence (Hard Version) | bitmasks constructive algorithms data structures dp implementation math | Statement | D2 | Codeforces Round 1007 (Div. 2) {2071} | PROGRAMMING | 1250.0 | Codeforces Round 1007 (Div. 2) Editorial | |
| 8757 | Goodbye, Banker Life | bitmasks combinatorics constructive algorithms math number theory | Statement | F | Codeforces Round 1006 (Div. 3) {2072} | PROGRAMMING | Codeforces Round 1006 (Div. 3) Editorial | ||
| 20107 | 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 | ||
| 278 | AND x OR | bitmasks constructive algorithms dp | Statement | F | Codeforces Round 1008 (Div. 1) {2077} | PROGRAMMING | 2500.0 | Codeforces Round 1008 (Div. 1, Div. 2) Editorial | |
| 3801 | Finding OR Sum | bitmasks constructive algorithms implementation interactive math | Statement | B | Codeforces Round 1008 (Div. 1) {2077} | PROGRAMMING | 1000.0 | Codeforces Round 1008 (Div. 1, Div. 2) Editorial | |
| 14113 | 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 | |
| 14984 | SUMdamental Decomposition | bitmasks constructive algorithms greedy implementation math | Statement | B | Codeforces Round 1022 (Div. 2) {2108} | PROGRAMMING | 1250.0 | Codeforces Round 1022 Editorial | |
| 11895 | Hacking Numbers (Easy Version) | bitmasks constructive algorithms interactive math number theory | Statement | C1 | Codeforces Round 1025 (Div. 2) {2109} | PROGRAMMING | 1250.0 | Codeforces Round 1025 (Div. 2) Editorial | |
| 16930 | A Good Problem | bitmasks constructive algorithms math | Statement | C | Codeforces Round 1035 (Div. 2) {2119} | PROGRAMMING | 1500.0 | Codeforces Round 1035 (Div. 2) Editorial | |
| 147 | Inter Active (Hard Version) | binary search bitmasks constructive algorithms graphs implementation interactive math probabilities | Statement | G2 | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) {2127} | PROGRAMMING | 2750.0 | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) Editorial | |
| 2249 | 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 | |
| 5198 | 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 | |
| 3802 | 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 | |
| 17869 | Cake Assignment | bitmasks constructive algorithms | Statement | A | Codeforces Round 1048 (Div. 1) {2138} | PROGRAMMING | 500.0 | Codeforces Round 1048 (Div. 1, Div. 2) Editorial | |
| 4311 | 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 | |
| 11327 | 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 | |
| 5591 | Find the Last Number | bitmasks constructive algorithms interactive math | Statement | D | Codeforces Round 1061 (Div. 2) {2156} | PROGRAMMING | 2000.0 | Codeforces Round 1061 (Div. 2) Editorial | |
| 22420 | Beautiful XOR | bitmasks constructive algorithms | Statement | C | Codeforces Round 1059 (Div. 3) {2162} | PROGRAMMING | Codeforces Round 1059 (Div. 3) Editorial | ||
| 931 | Intercepting Butterflies | bitmasks constructive algorithms graphs interactive | Statement | C | Testing Round 20 (Unrated, Communication Problems) {2168} | PROGRAMMING | Testing Round 20 Editorial (officially unofficial) | ||
| 14293 | Blackslex and Penguin Civilization | bitmasks constructive algorithms greedy math | Statement | D | Codeforces Round 1071 (Div. 3) {2179} | PROGRAMMING | Codeforces Round 1071 (Div. 3) Editorial | ||
| 6799 | 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 | |
| 5722 | 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 | |
| 14887 | XOR Convenience (Easy Version) | bitmasks brute force constructive algorithms math | Statement | C1 | Codeforces Round 1075 (Div. 2) {2189} | PROGRAMMING | 1250.0 | Codeforces Round 1075 (Div. 2) Editorial | |
| 6597 | XOR-convenience (Hard Version) | bitmasks brute force constructive algorithms math | Statement | C2 | Codeforces Round 1075 (Div. 2) {2189} | PROGRAMMING | 750.0 | Codeforces Round 1075 (Div. 2) Editorial | |
| 888 | Oriented Journey | bitmasks communication constructive algorithms graphs hashing interactive trees | Statement | C | Codeforces Round 1092 (Unrated, Div. 1, Based on THUPC 2026 — Finals) {2215} | PROGRAMMING | 1750.0 | 152930 | |
| 8967 | XOR, Expression and Two Binary Numbers | bitmasks constructive algorithms math number theory | Statement | D | Codeforces Round 1102 (Div. 2) {2234} | PROGRAMMING | 1750.0 | Tutorial | |
| 9328 | Nim Game Is XOR Game | bitmasks constructive algorithms games greedy math | Statement | A | Codeforces Round 1105 (Div. 1) {2239} | PROGRAMMING | 750.0 | Codeforces Round 1105 (Div. 1, Div. 2) Editorial | |
| 1540 | Product of Closures | bitmasks brute force constructive algorithms dp greedy implementation math | Statement | E | Educational Codeforces Round 192 (Rated for Div. 2) {2242} | PROGRAMMING | 155047 | ||
| 6836 | MEXOR | bitmasks constructive algorithms math | Statement | C | Spectral::Cup 2026 Round 3 (Codeforces Round 1110, Div. 1 + Div. 2) {2245} | PROGRAMMING | 1250.0 | Spectral::Cup 2026 Round 3 (Codeforces Round 1110, Div. 1 + Div. 2) Editorial | |
| 1063 | Xor Permutation Matrix | bitmasks chinese remainder theorem constructive algorithms math | Statement | D | Codeforces Round 1112 (Div. 1) {2249} | PROGRAMMING | 2250.0 | Codeforces Round 1112 (Div. 1, Div. 2) Editorial | |
| 3028 | Whiplash | bitmasks constructive algorithms math | Statement | F | Codeforces Round 1114 (Div. 3) {2254} | PROGRAMMING | Tutorial |