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Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 981 | Friends | binary search bitmasks data structures math | Statement | B | Bayan 2012-2013 Elimination Round (ACM ICPC Rules, English statements) {241} | PROGRAMMING | 2700 | ||
| 11788 | XOR on Segment | bitmasks data structures | Statement | E | Codeforces Round 149 (Div. 2) {242} | PROGRAMMING | Codeforces Round #149 (Div. 2) Tutorial | 2000 | |
| 4306 | Sausage Maximization | bitmasks data structures trees | Statement | E | Codeforces Round 173 (Div. 2) {282} | PROGRAMMING | Round #173 — Editorial | 2100 | |
| 1040 | Inna and Binary Logic | binary search bitmasks data structures | Statement | E | Codeforces Round 234 (Div. 2) {400} | PROGRAMMING | Codeforces Round #234 (Div. 2) — Tutorial | 2400 | |
| 463 | Design Tutorial: Increase the Constraints | bitmasks data structures fft | Statement | G | Codeforces Round 270 {472} | PROGRAMMING | Editorial | 2800 | |
| 7051 | New Year Tree | bitmasks data structures trees | Statement | E | Educational Codeforces Round 6 {620} | PROGRAMMING | Editorial of Educational Codeforces Round 6 | 2100 | |
| 875 | Yash And Trees | bitmasks data structures dfs and similar math number theory | Statement | G | Manthan, Codefest 16 {633} | PROGRAMMING | Manthan, Codefest 16: Editorials | 2700 | |
| 12466 | Vasiliy's Multiset | binary search bitmasks data structures trees | Statement | D | Codeforces Round 367 (Div. 2) {706} | PROGRAMMING | Tutorial | 1800 | |
| 2975 | Persistent Bookcase | bitmasks data structures dfs and similar implementation | Statement | D | Codeforces Round 368 (Div. 2) {707} | PROGRAMMING | 46662 | 2100 | |
| 3456 | 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 | |
| 204 | Sequence Recovery | bitmasks data structures greedy | Statement | F | Codeforces Round 408 (Div. 2) {796} | PROGRAMMING | Tutorial | 2800 | |
| 3705 | Choosing The Commander | bitmasks data structures trees | Statement | E | Educational Codeforces Round 23 {817} | PROGRAMMING | 52638 | 2100 | |
| 2489 | High Cry | binary search bitmasks combinatorics data structures divide and conquer | Statement | D | Codeforces Round 441 (Div. 1, by Moscow Team Olympiad) {875} | PROGRAMMING | Codeforces Round #441. Editorial. | 2200 | |
| 5467 | Danil and a Part-time Job | bitmasks data structures trees | Statement | E | Codeforces Round 442 (Div. 2) {877} | PROGRAMMING | 55362 | 2000 | |
| 5826 | Xor-MST | bitmasks constructive algorithms data structures | Statement | G | Educational Codeforces Round 32 {888} | PROGRAMMING | Educational Codeforces Round 32 - Editorial | 2300 | |
| 1908 | Palindromes in a Tree | bitmasks data structures divide and conquer trees | Statement | E | Codecraft-18 and Codeforces Round 458 (Div. 1 + Div. 2, combined) {914} | PROGRAMMING | Tutorial | 2400 | |
| 2140 | Substrings in a String | bitmasks brute force data structures string suffix structures strings | Statement | F | Codecraft-18 and Codeforces Round 458 (Div. 1 + Div. 2, combined) {914} | PROGRAMMING | Tutorial | 2900 | |
| 1084 | Shortest Path Queries | bitmasks data structures dsu graphs | Statement | G | Educational Codeforces Round 38 (Rated for Div. 2) {938} | PROGRAMMING | Educational Codeforces Round 38 — Editorial | 2900 | |
| 2173 | 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 |
| 2524 | Addition on Segments | bitmasks data structures divide and conquer dp | Statement | E | Avito Code Challenge 2018 {981} | PROGRAMMING | Avito Code Challenge 2018 — разбор | 2100 | |
| 927 | Sonya and Bitwise OR | bitmasks data structures divide and conquer | Statement | F | Codeforces Round 495 (Div. 2) {1004} | PROGRAMMING | 60443 | 2900 | |
| 3947 | The Wu | bitmasks brute force data structures | Statement | D | Codeforces Round 502 (in memory of Leopoldo Taravilse, Div. 1 + Div. 2) {1017} | PROGRAMMING | Разбор (англ.) | 1900 | |
| 2215 | Multidimensional Queries | bitmasks data structures | Statement | G | Educational Codeforces Round 56 (Rated for Div. 2) {1093} | PROGRAMMING | 63877 | 2200 | |
| 2426 | 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 | |
| 1015 | Hot is Cold | bitmasks data structures divide and conquer implementation | Statement | E | Forethought Future Cup - Elimination Round {1146} | PROGRAMMING | 66639 | 2400 | |
| 1008 | Magical Permutation | bitmasks brute force constructive algorithms data structures graphs math | Statement | E | Codeforces Round 558 (Div. 2) {1163} | PROGRAMMING | 66943 | 2800 | |
| 2041 | Count The Rectangles | bitmasks brute force data structures geometry sortings | Statement | E | Educational Codeforces Round 68 (Rated for Div. 2) {1194} | PROGRAMMING | Разбор Educational Codeforces Round 68 | 2200 | |
| 330 | Feeling Good | bitmasks data structures | Statement | G | Codeforces Round 583 (Div. 1 + Div. 2, based on Olympiad of Metropolises) {1214} | PROGRAMMING | Tutorial | 3100 | |
| 4629 | 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 | |
| 2023 | AND Segments | bitmasks combinatorics data structures dp two pointers | Statement | F | Educational Codeforces Round 84 (Rated for Div. 2) {1327} | PROGRAMMING | Educational Codeforces Round 84 Editorial | 2500 | |
| 655 | Joker | *special bitmasks data structures divide and conquer dsu | Statement | C | Baltic Olympiad in Informatics 2020, Day 1 (IOI, Unofficial Mirror Contest, Unrated) {1386} | PROGRAMMING | T | ||
| 1157 | Mercenaries | bitmasks combinatorics data structures math two pointers | Statement | G | Educational Codeforces Round 94 (Rated for Div. 2) {1400} | PROGRAMMING | 81942 | ||
| 1952 | Reverse and Swap | binary search bitmasks data structures divide and conquer | Statement | F | Codeforces Round 665 (Div. 2) {1401} | PROGRAMMING | 2500.0 | Codeforces Round #665 (Div. 2) Editorial | |
| 5031 | XOR Inverse | bitmasks data structures divide and conquer greedy strings trees | Statement | C | Codeforces Round 673 (Div. 1) {1416} | PROGRAMMING | 1250.0 | Codeforces Round #673 Editorial | 2000 |
| 248 | Cheat and Win | bitmasks data structures games trees | Statement | E | Codeforces Round 684 (Div. 1) {1439} | PROGRAMMING | 2500.0 | Codeforces Round #684[Div1 and Div2] Editorial | |
| 4080 | Xor Tree | binary search bitmasks data structures divide and conquer dp trees | Statement | C | Codeforces Round 683 (Div. 1, by Meet IT) {1446} | PROGRAMMING | 1250.0 | E | |
| 6774 | Strange Definition | bitmasks brute force data structures graphs math number theory | Statement | B | Codeforces Round 694 (Div. 1) {1470} | PROGRAMMING | 750.0 | 86464 | |
| 2744 | Pattern Matching | bitmasks data structures dfs and similar graphs sortings strings | Statement | E | Educational Codeforces Round 103 (Rated for Div. 2) {1476} | PROGRAMMING | 87356 | ||
| 1329 | Odd Mineral Resource | bitmasks data structures hashing probabilities trees | Statement | D | Codeforces Round 700 (Div. 1) {1479} | PROGRAMMING | 2250.0 | Editorial of Codeforces Round #700 | |
| 23197 | Box Fitting | binary search bitmasks data structures greedy | Statement | B | CodeCraft-21 and Codeforces Round 711 (Div. 2) {1498} | PROGRAMMING | 1000.0 | CodeCraft-21 and Codeforces Round #711 (Div. 2) Editorial | |
| 938 | Chips on a Board | bitmasks brute force data structures games sortings | Statement | G | Educational Codeforces Round 107 (Rated for Div. 2) {1511} | PROGRAMMING | 89634 | ||
| 350 | Phoenix and Bits | bitmasks data structures | Statement | H | Codeforces Global Round 14 {1515} | PROGRAMMING | 4250.0 | Editorial | |
| 92 | Submatrices | *special bitmasks data structures dp | Statement | H | Kotlin Heroes: Episode 7 {1533} | PROGRAMMING | Kotlin Heroes 7 — Editorial | ||
| 1836 | Stringforces | binary search bitmasks data structures dp greedy strings two pointers | Statement | E | Educational Codeforces Round 111 (Rated for Div. 2) {1550} | PROGRAMMING | Educational Codeforces Round 111 Editorial | ||
| 1625 | RBS | binary search bitmasks data structures dp | Statement | F | Educational Codeforces Round 115 (Rated for Div. 2) {1598} | PROGRAMMING | 95890 | ||
| 2315 | Binary Spiders | bitmasks data structures implementation sortings trees | Statement | D | Codeforces Round 765 (Div. 2) {1625} | PROGRAMMING | 2000.0 | Editorial of Codeforces Round #765 (Div. 2) | |
| 1481 | Minimal String Xoration | bitmasks data structures divide and conquer hashing strings | Statement | F | Codeforces Round 778 (Div. 1 + Div. 2, based on Technocup 2022 Final Round) {1654} | PROGRAMMING | 3000.0 | Editorial of Codeforces Round #778 (Div. 1 + Div. 2, based on Technocup 2022 Final Round) | 2800 |
| 3173 | 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 | |
| 9986 | 388535 (Easy Version) | bitmasks data structures math | Statement | D1 | Codeforces Round 779 (Div. 2) {1658} | PROGRAMMING | 1250.0 | Codeforces Round #779 (Div. 2) Editorial | |
| 1967 | 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 | |
| 1794 | MinimizOR | binary search bitmasks data structures dp greedy implementation | Statement | E | Codeforces Round 781 (Div. 2) {1665} | PROGRAMMING | 2250.0 | Codeforces Round #781 (Div. 2) Editorial | |
| 5752 | Passable Paths (hard version) | bitmasks data structures dfs and similar dp sortings trees | Statement | G2 | Codeforces Round 805 (Div. 3) {1702} | PROGRAMMING | 104763 | ||
| 2449 | Mark and Professor Koro | binary search bitmasks combinatorics data structures greedy | Statement | E | Codeforces Round 807 (Div. 2) {1705} | PROGRAMMING | 2500.0 | Codeforces Round #807 (Div 2.) Editorial | |
| 1317 | Swap and Maximum Block | bitmasks data structures divide and conquer dp | Statement | E | Educational Codeforces Round 133 (Rated for Div. 2) {1716} | PROGRAMMING | 105653 | ||
| 2187 | Xor-Subsequence (hard version) | bitmasks data structures dp strings trees | Statement | D2 | Codeforces Round 815 (Div. 2) {1720} | PROGRAMMING | 1000.0 | Codeforces Round #815 (Div. 2) Editorial | |
| 2547 | Prefix Function Queries | bitmasks brute force data structures hashing string suffix structures strings trees | Statement | E | Educational Codeforces Round 134 (Rated for Div. 2) {1721} | PROGRAMMING | 106416 | ||
| 1143 | Field Photography | bitmasks data structures sortings | Statement | F | COMPFEST 14 - Preliminary Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1725} | PROGRAMMING | Tutorial | ||
| 742 | Almost Sorted | bitmasks data structures dp | Statement | F | Codeforces Round 823 (Div. 2) {1730} | PROGRAMMING | 3000.0 | Codeforces Round #823 — editorial | 2700 |
| 633 | Keyboard Design | bitmasks data structures dp string suffix structures strings | Statement | F | Educational Codeforces Round 136 (Rated for Div. 2) {1739} | PROGRAMMING | Educational Codeforces Round 136 Editorial | ||
| 5543 | 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 | |
| 10265 | 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 | ||
| 1521 | 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 | |
| 1336 | Comfortably Numb | binary search bitmasks data structures divide and conquer dsu strings trees two pointers | Statement | F | Codeforces Round 845 (Div. 2) and ByteRace 2023 {1777} | PROGRAMMING | 2750.0 | Codeforces Round #845 (Div. 2) and ByteRace 2023 Editorial | |
| 1900 | Three Chairs | bitmasks brute force combinatorics data structures number theory sortings | Statement | F | Codeforces Round 846 (Div. 2) {1780} | PROGRAMMING | 2000.0 | 111841 | |
| 1948 | Walk the Runway | bitmasks brute force data structures dp graphs implementation sortings | Statement | E | Codeforces Round 870 (Div. 2) {1826} | PROGRAMMING | 2500.0 | Codeforces Round #870 (Div. 2) Editorial | 2400 |
| 1175 | 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 | |
| 1027 | 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 | |
| 14735 | Vampiric Powers, anyone? | bitmasks brute force data structures dp greedy | Statement | C | Codeforces Round 882 (Div. 2) {1847} | PROGRAMMING | 1500.0 | Tutorial | |
| 877 | XOR Partition | binary search bitmasks data structures divide and conquer greedy trees | Statement | F | Educational Codeforces Round 152 (Rated for Div. 2) {1849} | PROGRAMMING | 118752 | ||
| 7378 | Lisa and the Martians | bitmasks data structures greedy math sortings strings trees | Statement | F | Codeforces Round 888 (Div. 3) {1851} | PROGRAMMING | 118667 | ||
| 1262 | Rollbacks (Hard Version) | bitmasks data structures interactive trees | Statement | E2 | Codeforces Round 893 (Div. 2) {1858} | PROGRAMMING | 1000.0 | Codeforces Round #893 (Div. 2) Editorial | 2600 |
| 3036 | 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 | |
| 21245 | Data Structures Fan | bitmasks data structures | Statement | E | Codeforces Round 895 (Div. 3) {1872} | PROGRAMMING | Codeforces Round 895 (Div. 3) Editorial | ||
| 1459 | 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 | ||
| 20750 | Iva & Pav | binary search bitmasks data structures greedy | Statement | E | Codeforces Round 900 (Div. 3) {1878} | PROGRAMMING | Codeforces round #900 (Div.3) Editorial | ||
| 7117 | 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 | ||
| 1469 | 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 | ||
| 2067 | 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) | |
| 14807 | 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 | ||
| 1645 | Distance Learning Courses in MAC | binary search bitmasks data structures greedy implementation math | Statement | E | Codeforces Round 932 (Div. 2) {1935} | PROGRAMMING | 2500.0 | Codeforces Round #932 (Div. 2) Editorial | |
| 624 | Bitwise Paradox | bitmasks data structures greedy two pointers | Statement | D | Codeforces Round 930 (Div. 1) {1936} | PROGRAMMING | 2000.0 | Codeforces Round 930 (Div. 1, Div. 2) Editorial | |
| 2235 | Fenwick Tree | bitmasks brute force combinatorics data structures dp math trees | Statement | C | Codeforces Round 942 (Div. 1) {1967} | PROGRAMMING | 1250.0 | Tutorial | 2300 |
| 16784 | 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 |
| 1692 | Yasya and the Mysterious Tree | bitmasks data structures dfs and similar graphs strings trees | Statement | G | Codeforces Round 950 (Div. 3) {1980} | PROGRAMMING | 130135 | ||
| 1518 | array-value | binary search bitmasks data structures two pointers | Statement | F | Codeforces Round 956 (Div. 2) and ByteRace 2024 {1983} | PROGRAMMING | 2500.0 | ||
| 396 | Let Me Teach You a Lesson (Hard Version) | 2-sat bitmasks data structures dp graphs matrices two pointers | Statement | E2 | Codeforces Round 961 (Div. 2) {1995} | PROGRAMMING | 1500.0 | Video Tutorial | |
| 8584 | QED's Favorite Permutation | bitmasks data structures implementation sortings | Statement | D | Codeforces Round 979 (Div. 2) {2030} | PROGRAMMING | 1500.0 | Codeforces Round 979 Editorial | |
| 11497 | Alya and Permutation | bitmasks constructive algorithms data structures | Statement | C | Codeforces Global Round 27 {2035} | PROGRAMMING | 1000.0 | Codeforces Global Round 27 Editorial | |
| 854 | Divide OR Conquer | bitmasks data structures dp implementation | Statement | D | 2024-2025 ICPC, NERC, Southern and Volga Russian Regional Contest (Unrated, Online Mirror, ICPC Rules, Preferably Teams) {2038} | PROGRAMMING | 2400 | ||
| 340 | Xorderable Array | bitmasks data structures | Statement | J | 2024-2025 ICPC Asia Jakarta Regional Contest (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {2045} | PROGRAMMING | raRzKDJLPHcUnqTcwvGznwEdKiDWjEkd.pdf | 2600 | |
| 577 | MEX OR Mania | bitmasks data structures implementation | Statement | F | Codeforces Round 994 (Div. 2) {2049} | PROGRAMMING | 2750.0 | Codeforces Round #994 (Div. 2) Editorial | |
| 5823 | Eating | binary search bitmasks data structures greedy two pointers | Statement | D | Codeforces Round 1005 (Div. 2) {2064} | PROGRAMMING | 1750.0 | Codeforces Round 1005 (Div. 2) Editorial | |
| 1077 | 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 | |
| 609 | Maximize Nor | bitmasks data structures implementation | Statement | F | Codeforces Round 1019 (Div. 2) {2103} | PROGRAMMING | 3000.0 | 142149 | |
| 2108 | Maximum OR Popcount | binary search bitmasks brute force data structures greedy | Statement | E | Codeforces Global Round 29 (Div. 1 + Div. 2) {2147} | PROGRAMMING | 2500.0 | ||
| 6715 | Division Versus Addition | bitmasks data structures games | Statement | D | Squarepoint Challenge (Codeforces Round 1055, Div. 1 + Div. 2) {2152} | PROGRAMMING | 2500.0 | Squarepoint Challenge (Codeforces Round 1055, Div. 1 + Div. 2) Editorial | |
| 1292 | Blackslex and Plants | bitmasks data structures dp math | Statement | H | Codeforces Round 1071 (Div. 3) {2179} | PROGRAMMING | Codeforces Round 1071 (Div. 3) Editorial | ||
| 166 | Again Trees... (hard version) | bitmasks data structures dfs and similar dp fft trees | Statement | F2 | Codeforces Round 1078 (Div. 2) {2194} | PROGRAMMING | 1750.0 | Codeforces Round #1078 Editorial | |
| 277 | 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 | |
| 199 | Simons and Diophantus Equation | bitmasks brute force data structures number theory | Statement | G | Codeforces Round 1083 (Div. 2) {2205} | PROGRAMMING | 3250.0 | Tutorial |