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1 2 >Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 390 | Mutation | bitmasks dp math | Statement | C | All-Ukrainian School Olympiad in Informatics {76} | PROGRAMMING | All-Ukrainian School Olympiad in Informatics: editorial (A,B,C,D,E,F) | 2700 | |
| 282 | Bitonix' Patrol | bitmasks brute force combinatorics dfs and similar math | Statement | D | Codeforces Round 134 (Div. 1) {217} | PROGRAMMING | Editorial for Codeforces Round #134 | 2800 | |
| 1703 | Table | bitmasks combinatorics dp math | Statement | B | Codeforces Round 144 (Div. 1) {232} | PROGRAMMING | Editorial for Codeforces Round #144 | 2200 | |
| 1053 | Friends | binary search bitmasks data structures math | Statement | B | Bayan 2012-2013 Elimination Round (ACM ICPC Rules, English statements) {241} | PROGRAMMING | 2700 | ||
| 753 | Two Sets | bitmasks math | Statement | D | Codeforces Round 153 (Div. 1) {251} | PROGRAMMING | Editorial of Codeforces Round #153 | 2500 | |
| 16929 | 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 | |
| 1442 | Captains Mode | bitmasks dp games | Statement | C | Codeforces Round 222 (Div. 1) {377} | PROGRAMMING | Codeforces Round #222 — Problem Analysis | 2400 | |
| 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 | |
| 4794 | Roman and Numbers | bitmasks brute force combinatorics dp number theory | Statement | D | Codeforces Round 235 (Div. 2) {401} | PROGRAMMING | Codeforces Round #235 (Div. 2) — Tutorial | 2000 | |
| 2986 | Random Task | binary search bitmasks combinatorics dp math | Statement | D | Codeforces Round 247 (Div. 2) {431} | PROGRAMMING | Editorial Codeforces Round #247 (Div. 2) | 2200 | |
| 843 | Valera and Number | bitmasks dp math probabilities | Statement | E | Codeforces Round 252 (Div. 2) {441} | PROGRAMMING | Разбор Codeforces Round #252 (Div. 2) | 2700 | |
| 38407 | Dreamoon and WiFi | bitmasks brute force combinatorics dp math probabilities | Statement | B | Codeforces Round 272 (Div. 2) {476} | PROGRAMMING | 1300 | ||
| 6616 | Fox And Jumping | bitmasks brute force dp math | Statement | D | Codeforces Round 290 (Div. 2) {510} | PROGRAMMING | Codeforces Round #290 Editorial | 2100 | |
| 2951 | Permutations | bitmasks divide and conquer math | Statement | B2 | Rockethon 2015 {513} | PROGRAMMING | 16260 | 1800 | |
| 4421 | Anya and Cubes | binary search bitmasks brute force dp math meet-in-the-middle | Statement | E | Codeforces Round 297 (Div. 2) {525} | PROGRAMMING | Codeforces Round #297 (Div.2) Editorial | 2200 | |
| 3592 | Mike and Foam | bitmasks combinatorics dp math number theory | Statement | C | Codeforces Round 305 (Div. 1) {547} | PROGRAMMING | Codeforces Round #305 Editorial | 2700 | |
| 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 | |
| 982 | Yash And Trees | bitmasks data structures dfs and similar math number theory | Statement | G | Manthan, Codefest 16 {633} | PROGRAMMING | Manthan, Codefest 16: Editorials | 2700 | |
| 694 | Gambling Nim | bitmasks math matrices probabilities | Statement | A | CROC 2016 - Final Round [Private, For Onsite Finalists Only] {662} | PROGRAMMING | Editorial for CROC 2016 Finals and Codeforces Round #347 | 2400 | |
| 2682 | Binary Table | bitmasks brute force divide and conquer dp fft math | Statement | C | CROC 2016 - Final Round [Private, For Onsite Finalists Only] {662} | PROGRAMMING | Editorial for CROC 2016 Finals and Codeforces Round #347 | 2800 | |
| 1484 | LRU | bitmasks dp math probabilities | Statement | C | Codeforces Round 363 (Div. 1) {698} | PROGRAMMING | Solution | 2700 | |
| 1613 | Xor-matic Number of the Graph | bitmasks graphs math number theory trees | Statement | G | Intel Code Challenge Final Round (Div. 1 + Div. 2, Combined) {724} | PROGRAMMING | Tutorial | 2600 | |
| 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 | |
| 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 | |
| 579 | Random Elections | bitmasks brute force divide and conquer fft math | Statement | E | Codeforces Round 432 (Div. 1, based on IndiaHacks Final Round 2017) {850} | PROGRAMMING | Codeforces Round #432 editorial | 2800 | |
| 81 | Egg Roulette | bitmasks brute force divide and conquer math meet-in-the-middle | Statement | F | MemSQL Start[c]UP 3.0 - Round 2 (onsite finalists) {865} | PROGRAMMING | MemSQL Start[c]UP 3.0 Round 2 Editorial | 3300 | |
| 7834 | Square Subsets | bitmasks combinatorics dp math | Statement | C | Codeforces Round 448 (Div. 2) {895} | PROGRAMMING | Codeforces Round #448(Div.2) Editorial | 2000 | |
| 3980 | Unusual Sequences | bitmasks combinatorics dp math number theory | Statement | D | Codeforces Round 450 (Div. 2) {900} | PROGRAMMING | Codeforces Round #450(Div. 2). Editorial. | 2100 | |
| 878 | New Year and Entity Enumeration | bitmasks combinatorics dp math | Statement | E | Good Bye 2017 {908} | PROGRAMMING | Good Bye 2017 Editorial | 2400 | |
| 1275 | Sum the Fibonacci | bitmasks divide and conquer dp fft math | Statement | G | Codecraft-18 and Codeforces Round 458 (Div. 1 + Div. 2, combined) {914} | PROGRAMMING | Tutorial | 2500 | |
| 2055 | 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 | |
| 2074 | List Of Integers | binary search bitmasks brute force combinatorics math number theory | Statement | G | Educational Codeforces Round 37 (Rated for Div. 2) {920} | PROGRAMMING | T | 2300 | |
| 3841 | Mahmoud and Ehab and the xor-MST | bitmasks dp graphs implementation math | Statement | E | Codeforces Round 473 (Div. 2) {959} | PROGRAMMING | Codeforces round #473 editorial | 1900 | |
| 2997 | Mahmoud and Ehab and yet another xor task | bitmasks dp math matrices | Statement | F | Codeforces Round 473 (Div. 2) {959} | PROGRAMMING | Codeforces round #473 editorial | 2600 | |
| 2271 | 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 |
| 1064 | Pave the Parallelepiped | bitmasks brute force combinatorics math number theory | Statement | B | Codeforces Round 497 (Div. 1) {1007} | PROGRAMMING | Editorial for Codeforces Round #497 by Skyglow | 2400 | |
| 364 | Appropriate Team | bitmasks math number theory | Statement | G | Educational Codeforces Round 48 (Rated for Div. 2) {1016} | PROGRAMMING | Разбор Educational Codeforces Round 48 | 2800 | |
| 388 | X-mouse in the Campus | bitmasks math number theory | Statement | G | Educational Codeforces Round 49 (Rated for Div. 2) {1027} | PROGRAMMING | Educational Codeforces Round 49 Editorial | 2800 | |
| 513 | Boolean Computer | bitmasks brute force fft math | Statement | F | Lyft Level 5 Challenge 2018 - Elimination Round {1033} | PROGRAMMING | The Lyft Level 5 Challenge 2018 Elimination Round (Div. 1 + Div. 2) Editorial | 2800 | |
| 828 | Little C Loves 3 III | bitmasks dp math | Statement | E | Codeforces Round 511 (Div. 1) {1034} | PROGRAMMING | Codeforces Round #511 Editorial | 3200 | |
| 1170 | Maximum Matching | bitmasks brute force dfs and similar dp graphs | Statement | E | Codeforces Round 508 (Div. 2) {1038} | PROGRAMMING | Tutorial | 2400 | |
| 3211 | Make It One | bitmasks combinatorics dp math number theory shortest paths | Statement | F | Codeforces Round 519 by Botan Investments {1043} | PROGRAMMING | Codeforces Round #519 Editorial | 2500 | |
| 3873 | Segment Sum | bitmasks combinatorics dp math | Statement | E | Educational Codeforces Round 53 (Rated for Div. 2) {1073} | PROGRAMMING | 62742 | 2300 | |
| 268 | Mateusz and an Infinite Sequence | bitmasks brute force dp strings | Statement | H | Hello 2019 {1097} | PROGRAMMING | 64310 | 3000 | |
| 2610 | Please, another Queries on Array? | bitmasks data structures divide and conquer math number theory | Statement | F | Codeforces Round 538 (Div. 2) {1114} | PROGRAMMING | Codeforces Round #538 (Div. 2) Editorial | 2500 | |
| 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 | |
| 4486 | Median String | bitmasks math number theory strings | Statement | E | Codeforces Round 550 (Div. 3) {1144} | PROGRAMMING | 66307 | 1900 | |
| 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 | |
| 6809 | XOR Guessing | bitmasks interactive math | Statement | E | Educational Codeforces Round 71 (Rated for Div. 2) {1207} | PROGRAMMING | Educational Codeforces Round 71 Editorial | 1800 | |
| 4153 | Alex and Julian | bitmasks math number theory | Statement | D | Codeforces Round 586 (Div. 1 + Div. 2) {1220} | PROGRAMMING | Codeforces Round #586 Editorial | 1900 | |
| 9944 | p-binary | bitmasks brute force math | Statement | C | Technocup 2020 - Elimination Round 2 {1225} | PROGRAMMING | 70898 | 1600 | |
| 538 | Xor-Set | bitmasks divide and conquer math | Statement | F | Codeforces Round 602 (Div. 1, based on Technocup 2020 Elimination Round 3) {1261} | PROGRAMMING | Tutorial | 3100 | |
| 15223 | Make Good | bitmasks constructive algorithms math | Statement | C | Good Bye 2019 {1270} | PROGRAMMING | Разбор Goodbye 2019 | 1500 | |
| 723 | Around the World | bitmasks combinatorics dfs and similar dp graphs graphs math trees | Statement | D | Codeforces Round 618 (Div. 1) {1299} | PROGRAMMING | 1750.0 | Codeforces Round #618 Editorial | 2900 |
| 18639 | Adding Powers | bitmasks greedy implementation math number theory ternary search | Statement | C | Educational Codeforces Round 83 (Rated for Div. 2) {1312} | PROGRAMMING | 74640 | ||
| 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 | |
| 740 | Wise Men (Hard Version) | bitmasks dp math | Statement | F2 | Codeforces Global Round 7 {1326} | PROGRAMMING | 1500.0 | 74961 | 3200 |
| 7199 | Dreamoon Likes Sequences | bitmasks combinatorics dp math | Statement | B | Codeforces Round 631 (Div. 1) - Thanks, Denis aramis Shitov! {1329} | PROGRAMMING | 750.0 | Codeforces Round #631 Editorial | 1900 |
| 8519 | Walk on Matrix | bitmasks constructive algorithms math | Statement | D | Codeforces Round 630 (Div. 2) {1332} | PROGRAMMING | 1250.0 | Codeforces Round #630 Editorial | 1700 |
| 915 | Chiori and Doll Picking (easy version) | bitmasks brute force combinatorics math | Statement | E1 | Codeforces Round 635 (Div. 1) {1336} | PROGRAMMING | 1750.0 | Codeforces Round #635 Editorial | 2600 |
| 725 | Chiori and Doll Picking (hard version) | bitmasks brute force combinatorics math | Statement | E2 | Codeforces Round 635 (Div. 1) {1336} | PROGRAMMING | 1500.0 | Codeforces Round #635 Editorial | 3400 |
| 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 |
| 25096 | 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 |
| 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 |
| 14317 | AND, OR and square sum | bitmasks greedy math | Statement | D | Codeforces Global Round 8 {1368} | PROGRAMMING | 1750.0 | Codeforces Global Round 8: editorial | |
| 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 | |
| 788 | Omkar and Pies | bitmasks dfs and similar dp math | Statement | G | Codeforces Global Round 10 {1392} | PROGRAMMING | 3000.0 | Codeforces Global Round 10 — Editorial | |
| 1347 | Running Competition | bitmasks fft math number theory | Statement | G | Educational Codeforces Round 93 (Rated for Div. 2) {1398} | PROGRAMMING | Educational Codeforces Round 93 Editorial | ||
| 1226 | Mercenaries | bitmasks combinatorics data structures math two pointers | Statement | G | Educational Codeforces Round 94 (Rated for Div. 2) {1400} | PROGRAMMING | 81942 | ||
| 2790 | Two Different | bitmasks constructive algorithms divide and conquer greedy | Statement | F | Grakn Forces 2020 {1408} | PROGRAMMING | 2500.0 | Grakn Forces -- Editorial | |
| 3557 | Decryption | bitmasks constructive algorithms implementation math number theory | Statement | E | Codeforces Round 671 (Div. 2) {1419} | PROGRAMMING | 2250.0 | Codeforces Round #671 Editorial | |
| 38326 | Rock and Lever | bitmasks math | Statement | B | Codeforces Round 672 (Div. 2) {1420} | PROGRAMMING | 1000.0 | Editorial | |
| 36857 | XORwice | bitmasks greedy math | Statement | A | Codeforces Round 676 (Div. 2) {1421} | PROGRAMMING | 500.0 | Codeforces Round #676 (Div. 2) 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 |
| 965 | Yet Another DAG Problem | bitmasks dp flows math | Statement | G | Educational Codeforces Round 96 (Rated for Div. 2) {1430} | PROGRAMMING | Educational Codeforces Round 96 — 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 | |
| 8625 | Apollo versus Pan | bitmasks math | Statement | E | Good Bye 2020 {1466} | PROGRAMMING | 1500.0 | Good Bye 2020 Editorial | |
| 6842 | Strange Definition | bitmasks brute force data structures graphs math number theory | Statement | B | Codeforces Round 694 (Div. 1) {1470} | PROGRAMMING | 750.0 | 86464 | |
| 92512 | Odd Divisor | bitmasks math number theory | Statement | A | Codeforces Round 697 (Div. 3) {1475} | PROGRAMMING | Codeforces Round #697 (Div. 3) Editorial | ||
| 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 | |
| 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 | |
| 37264 | AND 0, Sum Big | bitmasks combinatorics math | Statement | B | Codeforces Round 716 (Div. 2) {1514} | PROGRAMMING | 1000.0 | Codeforces round #716 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 | |
| 8012 | Array Differentiation | bitmasks dp graphs math | Statement | D | Codeforces Global Round 15 {1552} | PROGRAMMING | 1000.0 | Editorial of Global Round 15 | |
| 13990 | 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 |
| 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 |
| 1480 | Sports Betting | bitmasks combinatorics dp graphs math probabilities | Statement | F | Deltix Round, Summer 2021 (open for everyone, rated, Div. 1 + Div. 2) {1556} | PROGRAMMING | 2500.0 | 94384 | 2500 |
| 11026 | Moamen and XOR | bitmasks combinatorics dp math | Statement | C | Codeforces Round 737 (Div. 2) {1557} | PROGRAMMING | 1750.0 | Codeforces Round #737 Editorial | |
| 49191 | Mocha and Math | bitmasks constructive algorithms math | Statement | A | Codeforces Round 738 (Div. 2) {1559} | PROGRAMMING | 500.0 | Tutorial (en) | 900 |
| 1984 | Bored Bakry | bitmasks greedy math two pointers | Statement | E | Codeforces Round 746 (Div. 2) {1592} | PROGRAMMING | 2500.0 | 95583 | |
| 22508 | Special Numbers | bitmasks math | Statement | B | Codeforces Round 747 (Div. 2) {1594} | PROGRAMMING | 1000.0 | 95525 | 1100 |
| 22706 | Array Elimination | bitmasks math number theory | Statement | A | Codeforces Round 751 (Div. 1) {1601} | PROGRAMMING | 500.0 | 95865 | 1300 |
| 11493 | Divan and bitwise operations | bitmasks combinatorics constructive algorithms dp math | Statement | C | Codeforces Round 757 (Div. 2) {1614} | PROGRAMMING | 1500.0 | Tutorial | 1500 |
| 18188 | And It's Non-Zero | bitmasks greedy math | Statement | B | Codeforces Global Round 18 {1615} | PROGRAMMING | 1000.0 | Global Round 18 Editorial | |
| 1389 | Keep XOR Low | bitmasks combinatorics divide and conquer dp math | Statement | H | Good Bye 2021: 2022 is NEAR {1616} | PROGRAMMING | 4000.0 | Good Bye 2021 -- Editorial | 3000 |
| 4821 | Reverse | bitmasks implementation math strings | Statement | F | Codeforces Round 760 (Div. 3) {1618} | PROGRAMMING | Codeforces Round #760 (Div. 3) Editorial | ||
| 7366 | BA-String | bitmasks brute force dp greedy implementation math shortest paths | Statement | C | Educational Codeforces Round 119 (Rated for Div. 2) {1620} | PROGRAMMING | 98061 | ||
| 1218 | Subsequences Galore | bitmasks combinatorics dp math | Statement | G | Educational Codeforces Round 119 (Rated for Div. 2) {1620} | PROGRAMMING | 98061 | ||
| 2297 | Math Test | bitmasks brute force greedy | Statement | E | Educational Codeforces Round 120 (Rated for Div. 2) {1622} | PROGRAMMING | Educational Codeforces Round 120 Editorial | ||
| 18398 | Ancient Civilization | bitmasks greedy math | Statement | A | Codeforces Round 765 (Div. 2) {1625} | PROGRAMMING | 500.0 | Editorial of Codeforces Round #765 (Div. 2) | |
| 14262 | 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 | |
| 23638 | Fortune Telling | bitmasks math | Statement | B | Codeforces Round 770 (Div. 2) {1634} | PROGRAMMING | 1250.0 | Codeforces Round #770 (Div. 2) editorial | |
| 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 |
| 3230 | 388535 (Hard Version) | bitmasks brute force data structures math | Statement | D2 | Codeforces Round 779 (Div. 2) {1658} | PROGRAMMING | 750.0 | Codeforces Round #779 (Div. 2) Editorial | |
| 10112 | 388535 (Easy Version) | bitmasks data structures math | Statement | D1 | Codeforces Round 779 (Div. 2) {1658} | PROGRAMMING | 1250.0 | Codeforces Round #779 (Div. 2) Editorial | |
| 2035 | 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 | |
| 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 | |
| 31741 | Maximal AND | bitmasks greedy math | Statement | H | Codeforces Round 784 (Div. 4) {1669} | PROGRAMMING | 102101 | 1300 | |
| 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 | |
| 824 | Formalism for Formalism | bitmasks dp math | Statement | F | Codeforces Round 791 (Div. 2) {1679} | PROGRAMMING | 3000.0 | Codeforces Round #791 (Div. 2) Editorial | |
| 13099 | Good Key, Bad Key | bitmasks brute force dp greedy math | Statement | G | Codeforces Round 806 (Div. 4) {1703} | PROGRAMMING | 104786 | ||
| 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 | |
| 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 |
| 7844 | Maximum AND | bitmasks brute force divide and conquer greedy math sortings | Statement | D | Educational Codeforces Round 134 (Rated for Div. 2) {1721} | PROGRAMMING | 106416 | ||
| 259 | Deducing Sortability | binary search bitmasks math | Statement | D | COMPFEST 14 - Preliminary Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1725} | PROGRAMMING | Tutorial | ||
| 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 | |
| 12659 | Even Subarrays | bitmasks brute force hashing math number theory | Statement | C | Codeforces Round 841 (Div. 2) and Divide by Zero 2022 {1731} | PROGRAMMING | 1500.0 | Codeforces Round #841 (Div. 2) and Divide By Zero 2022 Editorial | |
| 1030 | Zeros and Ones | bitmasks divide and conquer dp math | Statement | F | Codeforces Round 822 (Div. 2) {1734} | PROGRAMMING | 3250.0 | Codeforces Round #822 (Div.2) Editorial | |
| 13830 | Orray | bitmasks brute force greedy math | Statement | G | Codeforces Round 827 (Div. 4) {1742} | PROGRAMMING | 107962 | ||
| 446 | Antifibonacci Cut | bitmasks combinatorics dp math | Statement | G | Educational Codeforces Round 137 (Rated for Div. 2) {1743} | PROGRAMMING | Educational Codeforces Round 137 Editorial | 3000 | |
| 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 | |
| 7716 | Count GCD | bitmasks combinatorics dp math number theory | Statement | D | CodeTON Round 3 (Div. 1 + Div. 2, Rated, Prizes!) {1750} | PROGRAMMING | 1750.0 | CodeTON Round 3 (Div. 1 + Div. 2) Editorial | |
| 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 | ||
| 2892 | Carry Bit | bitmasks brute force combinatorics dp math | Statement | D | Pinely Round 1 (Div. 1 + Div. 2) {1761} | PROGRAMMING | 1750.0 | Pinely Round 1 (Div. 1 + Div. 2) Editorial | |
| 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 | |
| 1104 | Koxia and Sequence | bitmasks combinatorics math | Statement | F | Good Bye 2022: 2023 is NEAR {1770} | PROGRAMMING | 2500.0 | Good Bye 2022 -- Editorial | |
| 1724 | Hossam and Range Minimum Query | binary search bitmasks data structures hashing probabilities strings trees | Statement | F | Codeforces Round 837 (Div. 2) {1771} | PROGRAMMING | 3500.0 | Codeforces Round #837 (Div. 2) Editorial | |
| 568 | Game of Questions | bitmasks dp math probabilities | Statement | G | 2022-2023 ICPC, NERC, Northern Eurasia Onsite (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1773} | PROGRAMMING | 2800 | ||
| 15112 | Interesting Sequence | binary search bitmasks math | Statement | C | Codeforces Round 843 (Div. 2) {1775} | PROGRAMMING | 1500.0 | Codeforces Round #843 (Div. 2) Editorial | |
| 1198 | The Tree Has Fallen! | bitmasks dfs and similar math trees | Statement | E | Codeforces Round 848 (Div. 2) {1778} | PROGRAMMING | 2250.0 | Codeforces Round #848 (Div. 2) Editorial | |
| 5963 | Bit Guessing Game | binary search bitmasks interactive | Statement | D | Codeforces Round 846 (Div. 2) {1780} | PROGRAMMING | 1500.0 | 111841 | |
| 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 | |
| 4908 | Dasha and Nightmares | bitmasks hashing meet-in-the-middle | Statement | F | Codeforces Round 855 (Div. 3) {1800} | PROGRAMMING | Codeforces Round 855 (Div. 3) Editorial | ||
| 1564 | XOR Counting | bitmasks combinatorics dp math | Statement | D | Codeforces Round 865 (Div. 1) {1815} | PROGRAMMING | 2500.0 | Editorial of Codeforces Round #865 | 2600 |
| 11456 | Don't Blame Me | bitmasks combinatorics dp math | Statement | H | Codeforces Round 871 (Div. 4) {1829} | PROGRAMMING | Codeforces Round 871 (Div. 4) Editorial | 1700 | |
| 1210 | Twin Clusters | bitmasks math meet-in-the-middle probabilities | Statement | C | Codeforces Round 880 (Div. 1) {1835} | PROGRAMMING | 1500.0 | Codeforces Round 880 Editorial | |
| 25078 | Binary Cafe | bitmasks combinatorics math | Statement | B | Codeforces Round 878 (Div. 3) {1840} | PROGRAMMING | Codeforces Round #878 (Div.3) Editorial | ||
| 27878 | 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 | |
| 40570 | Sum in Binary Tree | bitmasks math trees | Statement | C | Codeforces Round 881 (Div. 3) {1843} | PROGRAMMING | Codeforces Round #881 (Div. 3) 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 | |
| 1120 | 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 | |
| 2153 | Vika and Wiki | binary search bitmasks combinatorics math | Statement | F | Codeforces Round 885 (Div. 2) {1848} | PROGRAMMING | 2750.0 | Codeforces Round #885 (Div.2) Editorial | |
| 7840 | Lisa and the Martians | bitmasks data structures greedy math sortings strings trees | Statement | F | Codeforces Round 888 (Div. 3) {1851} | PROGRAMMING | 118667 | ||
| 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 | |
| 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 | |
| 16547 | 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 | |
| 1441 | Jellyfish and Math | bitmasks dp graphs shortest paths | Statement | B | Codeforces Round 901 (Div. 1) {1874} | PROGRAMMING | 1250.0 | Codeforces Round 901 (Div. 1, Div. 2) Editorial | |
| 14153 | 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 | |
| 1518 | wxhtzdy ORO Tree | binary search bitmasks data structures dfs and similar math trees | Statement | G | Codeforces Round 900 (Div. 3) {1878} | PROGRAMMING | Codeforces round #900 (Div.3) Editorial | ||
| 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 | ||
| 1568 | Trees and XOR Queries Again | bitmasks data structures dfs and similar implementation math trees | Statement | F | Educational Codeforces Round 159 (Rated for Div. 2) {1902} | PROGRAMMING | Educational Codeforces Round 159 Editorial | ||
| 4582 | Kim's Quest | bitmasks combinatorics dp | Statement | K | 2023-2024 ICPC, NERC, Northern Eurasia Onsite (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1912} | PROGRAMMING | Tutorials (PDF) | 1800 | |
| 2118 | Yet Another Inversions Problem | bitmasks combinatorics data structures math | Statement | D | Codeforces Round 917 (Div. 2) {1917} | PROGRAMMING | 2250.0 | Editorial of Codeforces Round 917 (Div. 2) | |
| 17215 | XOR-distance | bitmasks dp greedy implementation math | Statement | C | Codeforces Round 922 (Div. 2) {1918} | PROGRAMMING | 1250.0 | Codeforces Round #922 (Div. 2) Editorial | |
| 9336 | Increasing Subsequences | bitmasks constructive algorithms math | Statement | E | Educational Codeforces Round 161 (Rated for Div. 2) {1922} | PROGRAMMING | Educational Codeforces Round 161 Editorial | ||
| 15291 | Vlad and an Odd Ordering | binary search bitmasks data structures dp implementation math number theory | Statement | E | Codeforces Round 928 (Div. 4) {1926} | PROGRAMMING | 126132 | ||
| 984 | Maximize the Difference | bitmasks brute force dfs and similar | Statement | F | think-cell Round 1 {1930} | PROGRAMMING | 2750.0 | think-cell Round 1 Editorial | |
| 1223 | Turtle Magic: Royal Turtle Shell Pattern | bitmasks brute force combinatorics math | Statement | G | Codeforces Round 929 (Div. 3) {1933} | PROGRAMMING | Codeforces Round 929 (Div. 3) Editorial | ||
| 1693 | 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 | |
| 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 | |
| 6043 | A BIT of an Inequality | bitmasks brute force dp math | Statement | D | Codeforces Round 940 (Div. 2) and CodeCraft-23 {1957} | PROGRAMMING | 1750.0 | Codeforces Round #940 and CodeCraft-23 (Div. 2) Editorial | 1900 |
| 2320 | Fenwick Tree | bitmasks brute force combinatorics data structures dp math trees | Statement | C | Codeforces Round 942 (Div. 1) {1967} | PROGRAMMING | 1250.0 | Tutorial | 2300 |
| 17182 | 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 |
| 1089 | Set | bitmasks brute force combinatorics dfs and similar divide and conquer dp math | Statement | F | Codeforces Round 947 (Div. 1 + Div. 2) {1975} | PROGRAMMING | 2500.0 | editorial_zh.pdf | 2600 |
| 20171 | Binary Colouring | bitmasks constructive algorithms greedy math | Statement | B | Codeforces Round 948 (Div. 2) {1977} | PROGRAMMING | 1250.0 | 129858 | 1100 |
| 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 | |
| 16843 | Turtle and an Infinite Sequence | bitmasks math | Statement | B | Codeforces Round 949 (Div. 2) {1981} | PROGRAMMING | 1000.0 | Simplified Chinese Tutorial | |
| 1955 | Number of k-good subarrays | bitmasks combinatorics divide and conquer dp math meet-in-the-middle | Statement | E | Codeforces Round 955 (Div. 2, with prizes from NEAR!) {1982} | PROGRAMMING | 2500.0 | 130839 | |
| 12646 | D-Function | bitmasks combinatorics math number theory | Statement | G | Codeforces Round 952 (Div. 4) {1985} | PROGRAMMING | Codeforces Round 952 (Div. 4) Editorial | ||
| 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 | |
| 1705 | Minecraft | bitmasks brute force dp math | Statement | G | Codeforces Round 959 sponsored by NEAR (Div. 1 + Div. 2) {1994} | PROGRAMMING | 2750.0 | 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 | |
| 5717 | Wooden Game | bitmasks greedy math trees | Statement | E | Codeforces Round 959 sponsored by NEAR (Div. 1 + Div. 2) {1994} | PROGRAMMING | 2000.0 | Video Tutorial | |
| 4154 | Expected Power | bitmasks brute force dp math number theory probabilities | Statement | E | Codeforces Round 976 (Div. 2) and Divide By Zero 9.0 {2020} | PROGRAMMING | 2000.0 | Tutorial for Codeforces Round 976 (Div. 2) and Divide By Zero 9.0 | |
| 26394 | 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 | |
| 18864 | Bitwise Balancing | bitmasks implementation math | Statement | C | Codeforces Round 976 (Div. 2) and Divide By Zero 9.0 {2020} | PROGRAMMING | 1250.0 | Tutorial for Codeforces Round 976 (Div. 2) and Divide By Zero 9.0 | |
| 276 | Bit Game (Easy Version) | bitmasks brute force games math | Statement | E1 | Codeforces Round 982 (Div. 2) {2027} | PROGRAMMING | 2000.0 | Codeforces Round #982 (Div. 2) Editorial | |
| 112 | Bit Game (Hard Version) | bitmasks dp math | Statement | E2 | Codeforces Round 982 (Div. 2) {2027} | PROGRAMMING | 1000.0 | Codeforces Round #982 (Div. 2) Editorial | |
| 563 | Alice's Adventures in Addition | bitmasks dp implementation | Statement | F | Codeforces Round 986 (Div. 2) {2028} | PROGRAMMING | 2500.0 | Codeforces Round 986 (Div. 2) Editorial | |
| 13912 | Shohag Loves XOR (Easy Version) | bitmasks brute force math number theory | Statement | C1 | CodeTON Round 9 (Div. 1 + Div. 2, Rated, Prizes!) {2039} | PROGRAMMING | 1000.0 | Editorial of CodeTON Round 9 (Div. 1 + Div. 2) | |
| 5122 | Shohag Loves XOR (Hard Version) | bitmasks brute force math number theory | Statement | C2 | CodeTON Round 9 (Div. 1 + Div. 2, Rated, Prizes!) {2039} | PROGRAMMING | 1500.0 | Editorial of CodeTON Round 9 (Div. 1 + Div. 2) | |
| 71 | Kevin and Puzzle (Hard Version) | bitmasks fft math | Statement | I2 | Codeforces Global Round 28 {2048} | PROGRAMMING | 3000.0 | Tutorial | |
| 1645 | Broken Queries | binary search bitmasks interactive | Statement | E | Codeforces Round 994 (Div. 2) {2049} | PROGRAMMING | 2250.0 | Codeforces Round #994 (Div. 2) Editorial | |
| 12660 | Bewitching Stargazer | bitmasks divide and conquer dp math | Statement | C | Good Bye 2024: 2025 is NEAR {2053} | PROGRAMMING | 1250.0 | Good Bye 2024: 2025 is NEAR Editorial | |
| 464 | Xor of Median (Easy Version) | bitmasks combinatorics dp math | Statement | F1 | Codeforces Round 997 (Div. 2) {2056} | PROGRAMMING | 2750.0 | Codeforces Round #997 (Div. 2) Editorial | |
| 14207 | Trip to the Olympiad | bitmasks constructive algorithms greedy math | Statement | C | Hello 2025 {2057} | PROGRAMMING | 1500.0 | ||
| 2588 | Bitwise Slides | bitmasks combinatorics dp math | Statement | C | Codeforces Round 1004 (Div. 1) {2066} | PROGRAMMING | 1250.0 | 139415 | |
| 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 | |
| 6900 | Infinite Sequence (Easy Version) | bitmasks dp math | Statement | D1 | Codeforces Round 1007 (Div. 2) {2071} | PROGRAMMING | 1750.0 | 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 | ||
| 2540 | Counting Necessary Nodes | bitmasks divide and conquer implementation math | Statement | F | Codeforces Round 1009 (Div. 3) {2074} | PROGRAMMING | Codeforces Round 1009 (Div. 3) — Editorial | ||
| 6067 | Equalization | bitmasks brute force dp greedy math | Statement | D | Educational Codeforces Round 176 (Rated for Div. 2) {2075} | PROGRAMMING | Educational Codeforces Round 176 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 | |
| 4336 | Math Division | bitmasks dp math probabilities | Statement | A | Codeforces Round 1010 (Div. 1, Unrated) {2081} | PROGRAMMING | 500.0 | Codeforces Round 1010 (Div. 1, Div. 2, based on Zhili Cup 2025) Editorial | |
| 1710 | Zebra-like Numbers | bitmasks brute force dfs and similar dp math | Statement | E | Educational Codeforces Round 177 (Rated for Div. 2) {2086} | PROGRAMMING | Educational Codeforces Round 177 Editorial | ||
| 238 | Wonderful XOR Problem | bitmasks combinatorics dp fft math | Statement | H | Neowise Labs Contest 1 (Codeforces Round 1018, Div. 1 + Div. 2) {2096} | PROGRAMMING | 3500.0 | Neowise Labs Contest 1 (Codeforces Round 1018, Div. 1 + Div. 2) Editorial | |
| 5731 | Wonderful Lightbulbs | bitmasks math | Statement | D | Neowise Labs Contest 1 (Codeforces Round 1018, Div. 1 + Div. 2) {2096} | PROGRAMMING | 1750.0 | Neowise Labs Contest 1 (Codeforces Round 1018, Div. 1 + Div. 2) Editorial | |
| 565 | Homework | bitmasks math matrices | Statement | D | Codeforces Round 1021 (Div. 1) {2097} | PROGRAMMING | 2000.0 | 142316 | |
| 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 | |
| 5670 | Small Operations | binary search bitmasks brute force dfs and similar dp math number theory sortings | Statement | F | Codeforces Round 1027 (Div. 3) {2114} | PROGRAMMING | 143268 | ||
| 2104 | Build an Array | bitmasks dp math number theory | Statement | G | Codeforces Round 1027 (Div. 3) {2114} | PROGRAMMING | 143268 | ||
| 2933 | Gellyfish and Forget-Me-Not | bitmasks games math | Statement | D | Codeforces Round 1028 (Div. 1) {2115} | PROGRAMMING | 2250.0 | Codeforces Round 1028 (Div.1, Div.2) Editorial | |
| 19128 | Make It Beautiful | bitmasks greedy math | Statement | C | Codeforces Round 1030 (Div. 2) {2118} | PROGRAMMING | 1000.0 | Codeforces Round 1030 (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 | |
| 3915 | Wafu! | bitmasks brute force dp math | Statement | G | Codeforces Round 1042 (Div. 3) {2131} | PROGRAMMING | Codeforces Round 1042 (Div. 3) 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 | |
| 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 | |
| 3598 | Encode and Decode (Hard Version) | bitmasks interactive math | Statement | A2 | Testing Round 20 (Unrated, Communication Problems) {2168} | PROGRAMMING | Testing Round 20 Editorial (officially unofficial) | ||
| 9112 | Removal of a Sequence (Easy Version) | binary search bitmasks geometry implementation math number theory | Statement | D1 | Educational Codeforces Round 184 (Rated for Div. 2) {2169} | PROGRAMMING | Educational Codeforces Round 184 Editorial | ||
| 2493 | Sakura Adachi and Optimal Sequences | bitmasks combinatorics greedy math | Statement | G | Codeforces Round 1065 (Div. 3) {2171} | PROGRAMMING | Codeforces Round 1065 (Div. 3) Editorial | ||
| 3912 | Taiga's Carry Chains | bitmasks brute force dp greedy | Statement | D | Codeforces Round 1068 (Div. 2) {2173} | PROGRAMMING | 1750.0 | ||
| 1591 | Omega Numbers | bitmasks dp math number theory | Statement | F | Codeforces Round 1070 (Div. 2) {2176} | PROGRAMMING | 2750.0 | Codeforces Round 1070 (Div.2) Editorial | |
| 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 | ||
| 1380 | Blackslex and Plants | bitmasks data structures dp math | Statement | H | 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 | |
| 1815 | No Effect XOR | bitmasks math | Statement | E | Codeforces Global Round 31 (Div. 1 + Div. 2) {2180} | PROGRAMMING | 2000.0 | Codeforces Global Round 31 | |
| 722 | Cool Problem | bitmasks brute force divide and conquer dp math | Statement | D | Codeforces Round 1077 (Div. 1) {2187} | PROGRAMMING | 2000.0 | 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 | |
| 11825 | Secret message | bitmasks math | Statement | C | Codeforces Round 1078 (Div. 2) {2194} | PROGRAMMING | 1750.0 | Codeforces Round #1078 Editorial | |
| 317 | 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 | |
| 8138 | Test Generator | binary search bitmasks greedy math | Statement | C | Educational Codeforces Round 187 (Rated for Div. 2) {2203} | PROGRAMMING | Educational Codeforces Round 187 Editorial | ||
| 3369 | AND-array | bitmasks combinatorics math | Statement | D | Nebius Round 2 (Codeforces Round 1088, Div. 1 + Div. 2) {2211} | PROGRAMMING | 2000.0 | Nebius Round 2 and Codeforces Round 1088 Editorial | |
| 921 | Interval Game | bitmasks combinatorics dp games greedy math probabilities | Statement | F | Codeforces Round 1091 (Div. 2) and CodeCraft 26 {2217} | PROGRAMMING | 2750.0 | Tutorial | |
| 2423 | Seek the Truth | binary search bitmasks interactive | Statement | E | Spectral::Cup 2026 Round 1 (Codeforces Round 1094, Div. 1 + Div. 2) {2222} | PROGRAMMING | 2250.0 | Spectral::Cup 2026 Round 1 (Codeforces Round 1094, Div. 1 + Div. 2) Editorial | |
| 8546 | Exceptional Segments | bitmasks brute force math | Statement | D | Educational Codeforces Round 189 (Rated for Div. 2) {2225} | PROGRAMMING | Tutorial | ||
| 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 | |
| 639 | lce4113 and Security Game | bitmasks interactive probabilities | Statement | E | Codeforces Round 1108 (Div. 2) {2246} | PROGRAMMING | 2250.0 | Codeforces Round 1108 (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 | |
| 1513 | Generational Triplets | bitmasks combinatorics dp math | Statement | E | Codeforces Round 1115 (Div. 2) {2252} | PROGRAMMING | 2250.0 | 155741 |