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< 1 2 3Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 2164 | Sasha and the Happy Tree Cutting | bitmasks brute force dp fft graphs greedy trees | Statement | E | Codeforces Round 926 (Div. 2) {1929} | PROGRAMMING | 2500.0 | Codeforces Round #926 (Div. 2) Editorial. | |
| 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 | ||
| 4268 | XOR Break --- Solo Version | bitmasks constructive algorithms greedy | Statement | D1 | Codeforces Round 931 (Div. 2) {1934} | PROGRAMMING | 1500.0 | Tutorial | |
| 1843 | XOR Break --- Game Version | bitmasks games greedy interactive | Statement | D2 | Codeforces Round 931 (Div. 2) {1934} | PROGRAMMING | 1250.0 | Tutorial | |
| 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 | |
| 8793 | 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 | |
| 725 | 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 | |
| 18430 | Equal XOR | bitmasks constructive algorithms | Statement | B | Codeforces Round 934 (Div. 2) {1944} | PROGRAMMING | 1000.0 | Codeforces Round #934 (Div1, Div2) Editorial | |
| 988 | GCD is Greater | bitmasks brute force number theory | Statement | H | Codeforces Round 935 (Div. 3) {1945} | PROGRAMMING | 127377 | ||
| 5720 | 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 | |
| 1017 | MST with Matching | bitmasks brute force trees | Statement | G | Educational Codeforces Round 163 (Rated for Div. 2) {1948} | PROGRAMMING | Educational Codeforces Round 163 Editorial | ||
| 6438 | Shuffling Songs | bitmasks dp graphs implementation strings | Statement | G | Codeforces Round 937 (Div. 4) {1950} | PROGRAMMING | Codeforces Round 937 (Div. 4) 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 | ||
| 4890 | 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) | |
| 20814 | 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 |
| 6045 | 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 |
| 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 |
| 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 |
| 579 | Min-Fund Prison (Hard) | bitmasks dfs and similar dp graphs trees | Statement | G3 | Helvetic Coding Contest 2024 online mirror (teams allowed, unrated) {1970} | PROGRAMMING | Helvetic Coding Contest 2024 Editorial | 2400 | |
| 17187 | 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 |
| 358 | Maximum GCD Sum Queries | bitmasks brute force dp implementation number theory | Statement | F | Codeforces Round 945 (Div. 2) {1973} | PROGRAMMING | 3000.0 | Editorial for Codeforces Round #945 (Div. 2) | 3100 |
| 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 |
| 2454 | XORificator | bitmasks brute force greedy hashing | Statement | D | Codeforces Round 948 (Div. 2) {1977} | PROGRAMMING | 2000.0 | 129858 | 2300 |
| 8002 | 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 | |
| 26861 | XOR Sequences | bitmasks greedy | Statement | B | Codeforces Round 951 (Div. 2) {1979} | PROGRAMMING | 1000.0 | Codeforces Round 951 (Div. 2) Editorial | |
| 1796 | Yasya and the Mysterious Tree | bitmasks data structures dfs and similar graphs strings trees | Statement | G | Codeforces Round 950 (Div. 3) {1980} | PROGRAMMING | 130135 | ||
| 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 | |
| 16847 | 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 | |
| 1614 | array-value | binary search bitmasks data structures two pointers | Statement | F | Codeforces Round 956 (Div. 2) and ByteRace 2024 {1983} | PROGRAMMING | 2500.0 | ||
| 362 | Your Loss | bitmasks brute force trees | Statement | G | Codeforces Round 956 (Div. 2) and ByteRace 2024 {1983} | PROGRAMMING | 3000.0 | ||
| 12648 | D-Function | bitmasks combinatorics math number theory | Statement | G | Codeforces Round 952 (Div. 4) {1985} | PROGRAMMING | Codeforces Round 952 (Div. 4) Editorial | ||
| 20707 | 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) | |
| 23699 | Substring and Subsequence | bitmasks brute force dp graphs greedy hashing strings trees | Statement | B | Educational Codeforces Round 167 (Rated for Div. 2) {1989} | PROGRAMMING | Educational Codeforces Round 167 Editorial | ||
| 7966 | Grid Puzzle | bitmasks dp greedy | Statement | D | Codeforces Round 960 (Div. 2) {1990} | PROGRAMMING | 1750.0 | Video Tutorial | |
| 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 | |
| 19266 | AND Reconstruction | bitmasks constructive algorithms greedy | Statement | B | Pinely Round 4 (Div. 1 + Div. 2) {1991} | PROGRAMMING | 500.0 | Video Tutorial | |
| 745 | Xor-Grid Problem | bitmasks dp | Statement | E | Codeforces Round 963 (Div. 2) {1993} | PROGRAMMING | 2750.0 | Editorial of Codeforces Round 963 (Div. 2) | |
| 1706 | Minecraft | bitmasks brute force dp math | Statement | G | Codeforces Round 959 sponsored by NEAR (Div. 1 + Div. 2) {1994} | PROGRAMMING | 2750.0 | Video Tutorial | |
| 19917 | 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 | |
| 5718 | Wooden Game | bitmasks greedy math trees | Statement | E | Codeforces Round 959 sponsored by NEAR (Div. 1 + Div. 2) {1994} | PROGRAMMING | 2000.0 | Video Tutorial | |
| 421 | 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 | |
| 3070 | Cases | bitmasks brute force combinatorics dfs and similar dp graphs greedy strings | Statement | D | Codeforces Round 961 (Div. 2) {1995} | PROGRAMMING | 2250.0 | Video Tutorial | |
| 4156 | 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 | |
| 26396 | 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 | |
| 18871 | 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 | |
| 2134 | Best Subsequence | bitmasks dfs and similar flows graph matchings graphs | Statement | E | Educational Codeforces Round 171 (Rated for Div. 2) {2026} | PROGRAMMING | Educational Codeforces Round 171 Editorial | ||
| 277 | 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 | |
| 113 | Message Spread | bitmasks combinatorics dp | Statement | H | Refact.ai Match 1 (Codeforces Round 985) {2029} | PROGRAMMING | 5000.0 | Refact.ai Match 1 (Codeforces Round 985) Editorial | |
| 8942 | QED's Favorite Permutation | bitmasks data structures implementation sortings | Statement | D | Codeforces Round 979 (Div. 2) {2030} | PROGRAMMING | 1500.0 | Codeforces Round 979 Editorial | |
| 11851 | Alya and Permutation | bitmasks constructive algorithms data structures | Statement | C | Codeforces Global Round 27 {2035} | PROGRAMMING | 1000.0 | Codeforces Global Round 27 Editorial | |
| 1871 | Library of Magic | binary search bitmasks constructive algorithms interactive | Statement | G | Codeforces Round 984 (Div. 3) {2036} | PROGRAMMING | Codeforces Round 984 (Div. 3) Editorial | ||
| 5552 | XORificator 3000 | bitmasks dp number theory | Statement | F | Codeforces Round 984 (Div. 3) {2036} | PROGRAMMING | Codeforces Round 984 (Div. 3) Editorial | ||
| 910 | 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 | ||
| 13915 | 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) | |
| 5124 | 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) | |
| 2105 | Cube | bitmasks dp | Statement | C | 2024 ICPC Asia Taichung Regional Contest (Unrated, Online Mirror, ICPC Rules, Preferably Teams) {2041} | PROGRAMMING | Problem Analysis and Hints (PDF) | ||
| 1879 | Matrix Transformation | bitmasks brute force dfs and similar graphs implementation | Statement | E | Educational Codeforces Round 173 (Rated for Div. 2) {2043} | PROGRAMMING | Educational Codeforces Round 173 Editorial | ||
| 931 | Nim | bitmasks dp games | Statement | F | Educational Codeforces Round 173 (Rated for Div. 2) {2043} | PROGRAMMING | Educational Codeforces Round 173 Editorial | ||
| 357 | 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 | |
| 15529 | Kevin and Binary Strings | bitmasks brute force greedy strings | Statement | C | Codeforces Global Round 28 {2048} | PROGRAMMING | 1000.0 | Tutorial | |
| 71 | Kevin and Puzzle (Hard Version) | bitmasks fft math | Statement | I2 | Codeforces Global Round 28 {2048} | PROGRAMMING | 3000.0 | Tutorial | |
| 1646 | Broken Queries | binary search bitmasks interactive | Statement | E | Codeforces Round 994 (Div. 2) {2049} | PROGRAMMING | 2250.0 | Codeforces Round #994 (Div. 2) Editorial | |
| 608 | MEX OR Mania | bitmasks data structures implementation | Statement | F | Codeforces Round 994 (Div. 2) {2049} | PROGRAMMING | 2750.0 | Codeforces Round #994 (Div. 2) Editorial | |
| 2523 | Snakes | bitmasks dp graphs | Statement | G | Codeforces Round 995 (Div. 3) {2051} | PROGRAMMING | 137623 | ||
| 12661 | 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 | |
| 371 | Xor of Median (Hard Version) | bitmasks combinatorics | Statement | F2 | Codeforces Round 997 (Div. 2) {2056} | PROGRAMMING | 1250.0 | Codeforces Round #997 (Div. 2) 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 | |
| 14210 | Trip to the Olympiad | bitmasks constructive algorithms greedy math | Statement | C | Hello 2025 {2057} | PROGRAMMING | 1500.0 | ||
| 4108 | Kevin and And | bitmasks brute force dp greedy | Statement | E | IAEPC Preliminary Contest (Codeforces Round 999, Div. 1 + Div. 2) {2061} | PROGRAMMING | 2000.0 | IAEPC Preliminary Contest (Codeforces Round 999, Div. 1 + Div. 2) Editorial | |
| 207 | Galaxy Generator | bitmasks combinatorics dp | Statement | H | Ethflow Round 1 (Codeforces Round 1001, Div. 1 + Div. 2) {2062} | PROGRAMMING | 4500.0 | Ethflow Round 1 (Codeforces Round 1001, Div. 1 + Div. 2) Editorial | |
| 6033 | 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 | |
| 2588 | Bitwise Slides | bitmasks combinatorics dp math | Statement | C | Codeforces Round 1004 (Div. 1) {2066} | PROGRAMMING | 1250.0 | 139415 | |
| 1136 | 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 | |
| 6905 | Infinite Sequence (Easy Version) | bitmasks dp math | Statement | D1 | Codeforces Round 1007 (Div. 2) {2071} | PROGRAMMING | 1750.0 | Codeforces Round 1007 (Div. 2) Editorial | |
| 8759 | 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 | ||
| 20113 | 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 | ||
| 22495 | XOR and Triangle | binary search bitmasks brute force greedy | Statement | C | Codeforces Round 1009 (Div. 3) {2074} | PROGRAMMING | Codeforces Round 1009 (Div. 3) — Editorial | ||
| 2541 | Counting Necessary Nodes | bitmasks divide and conquer implementation math | Statement | F | Codeforces Round 1009 (Div. 3) {2074} | PROGRAMMING | Codeforces Round 1009 (Div. 3) — Editorial | ||
| 6077 | Equalization | bitmasks brute force dp greedy math | Statement | D | Educational Codeforces Round 176 (Rated for Div. 2) {2075} | PROGRAMMING | Educational Codeforces Round 176 Editorial | ||
| 1216 | XOR Matrix | bitmasks dp | Statement | E | Educational Codeforces Round 176 (Rated for Div. 2) {2075} | PROGRAMMING | Educational Codeforces Round 176 Editorial | ||
| 150 | RGB Walking | bitmasks chinese remainder theorem dfs and similar graphs number theory | Statement | G | Codeforces Round 1008 (Div. 1) {2077} | PROGRAMMING | 3000.0 | Codeforces Round 1008 (Div. 1, Div. 2) 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 | |
| 3802 | 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 | |
| 4341 | 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 | |
| 384 | Quaternary Matrix | bitmasks greedy | Statement | C | Codeforces Round 1010 (Div. 1, Unrated) {2081} | PROGRAMMING | 1750.0 | Codeforces Round 1010 (Div. 1, Div. 2, based on Zhili Cup 2025) Editorial | |
| 14119 | 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 | |
| 1711 | 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 | ||
| 6061 | Hackers and Neural Networks | bitmasks brute force greedy | Statement | F | Codeforces Round 1016 (Div. 3) {2093} | PROGRAMMING | Codeforces Round 1016 (Div. 3) Editorial | ||
| 12622 | Skibidi Table | bitmasks implementation | Statement | D | Codeforces Round 1016 (Div. 3) {2093} | PROGRAMMING | Codeforces Round 1016 (Div. 3) Editorial | ||
| 19192 | Boneca Ambalabu | bitmasks | Statement | E | Codeforces Round 1017 (Div. 4) {2094} | PROGRAMMING | Codeforces Round 1017 (Div. 4) Editorial | ||
| 239 | 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 | |
| 5732 | 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 | |
| 652 | Maximize Nor | bitmasks data structures implementation | Statement | F | Codeforces Round 1019 (Div. 2) {2103} | PROGRAMMING | 3000.0 | 142149 | |
| 14986 | SUMdamental Decomposition | bitmasks constructive algorithms greedy implementation math | Statement | B | Codeforces Round 1022 (Div. 2) {2108} | PROGRAMMING | 1250.0 | Codeforces Round 1022 Editorial | |
| 11896 | 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 | |
| 17861 | Slice to Survive | bitmasks greedy | Statement | B | Codeforces Round 1025 (Div. 2) {2109} | PROGRAMMING | 1000.0 | Codeforces Round 1025 (Div. 2) Editorial | |
| 5673 | 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 | ||
| 2106 | Build an Array | bitmasks dp math number theory | Statement | G | Codeforces Round 1027 (Div. 3) {2114} | PROGRAMMING | 143268 | ||
| 2934 | 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 | |
| 19134 | Make It Beautiful | bitmasks greedy math | Statement | C | Codeforces Round 1030 (Div. 2) {2118} | PROGRAMMING | 1000.0 | Codeforces Round 1030 (Div. 2) Editorial | |
| 16933 | A Good Problem | bitmasks constructive algorithms math | Statement | C | Codeforces Round 1035 (Div. 2) {2119} | PROGRAMMING | 1500.0 | Codeforces Round 1035 (Div. 2) Editorial | |
| 737 | And Constraint | bitmasks dp greedy implementation | Statement | E | Codeforces Round 1035 (Div. 2) {2119} | PROGRAMMING | 2500.0 | 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 | |
| 5199 | 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 | ||
| 6423 | By the Assignment | bitmasks dfs and similar dsu graphs | Statement | C | Codeforces Round 1046 (Div. 1) {2135} | PROGRAMMING | 1750.0 | Codeforces Round 1046 (Div. 1, Div. 2) Editorial | |
| 3612 | Maple and Tree Beauty (Hard Version) | bitmasks brute force dfs and similar divide and conquer dp fft trees | Statement | C2 | Codeforces Round 1048 (Div. 1) {2138} | PROGRAMMING | 750.0 | Codeforces Round 1048 (Div. 1, Div. 2) Editorial | |
| 17872 | Cake Assignment | bitmasks constructive algorithms | Statement | A | Codeforces Round 1048 (Div. 1) {2138} | PROGRAMMING | 500.0 | Codeforces Round 1048 (Div. 1, Div. 2) Editorial | |
| 2256 | Prime Gaming (Easy Version) | bitmasks combinatorics dp | Statement | E1 | Codeforces Round 1049 (Div. 2) {2140} | PROGRAMMING | 1750.0 | Codeforces Round 1049 (Div. 2) Editorial | |
| 1306 | Prime Gaming (Hard Version) | bitmasks combinatorics dp probabilities | Statement | E2 | Codeforces Round 1049 (Div. 2) {2140} | PROGRAMMING | 1000.0 | Codeforces Round 1049 (Div. 2) Editorial | |
| 4312 | 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 | |
| 11329 | 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 | |
| 2333 | 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 | ||
| 8890 | 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 | |
| 23341 | Bitwise Reversion | bitmasks | Statement | B | Codeforces Round 1057 (Div. 2) {2153} | PROGRAMMING | 750.0 | Codeforces Round 1057 (Div. 2) Editorial | |
| 5595 | 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 | |
| 15925 | Reverse XOR | bitmasks | Statement | C | Codeforces Round 1058 (Div. 2) {2160} | PROGRAMMING | 1250.0 | Codeforces Round 1058 Editorial | |
| 104 | Bitwise And Equals | bitmasks | Statement | G | Pinely Round 5 (Div. 1 + Div. 2) {2161} | PROGRAMMING | 3750.0 | ||
| 22430 | Beautiful XOR | bitmasks constructive algorithms | Statement | C | Codeforces Round 1059 (Div. 3) {2162} | PROGRAMMING | Codeforces Round 1059 (Div. 3) Editorial | ||
| 6077 | Binary Wine | bitmasks greedy | Statement | C | Codeforces Round 1064 (Div. 1) {2165} | PROGRAMMING | 1500.0 | 148452 | |
| 931 | Intercepting Butterflies | bitmasks constructive algorithms graphs interactive | Statement | C | Testing Round 20 (Unrated, Communication Problems) {2168} | PROGRAMMING | Testing Round 20 Editorial (officially unofficial) | ||
| 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 | ||
| 882 | Build XOR on a Segment | bitmasks dp | Statement | F | Educational Codeforces Round 185 (Rated for Div. 2) {2170} | PROGRAMMING | Educational Codeforces Round 185 Editorial | ||
| 2494 | Sakura Adachi and Optimal Sequences | bitmasks combinatorics greedy math | Statement | G | Codeforces Round 1065 (Div. 3) {2171} | PROGRAMMING | Codeforces Round 1065 (Div. 3) Editorial | ||
| 12621 | Renako Amaori and XOR Game (hard version) | bitmasks games greedy | Statement | C2 | Codeforces Round 1065 (Div. 3) {2171} | PROGRAMMING | Codeforces Round 1065 (Div. 3) Editorial | ||
| 3913 | Taiga's Carry Chains | bitmasks brute force dp greedy | Statement | D | Codeforces Round 1068 (Div. 2) {2173} | PROGRAMMING | 1750.0 | ||
| 1594 | Omega Numbers | bitmasks dp math number theory | Statement | F | Codeforces Round 1070 (Div. 2) {2176} | PROGRAMMING | 2750.0 | Codeforces Round 1070 (Div.2) Editorial | |
| 24087 | Optimal Shifts | bitmasks greedy strings | Statement | B | Codeforces Round 1070 (Div. 2) {2176} | PROGRAMMING | 1000.0 | Codeforces Round 1070 (Div.2) Editorial | |
| 14295 | 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 | ||
| 6803 | 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 | |
| 1353 | Christmas Reindeer (easy version) | bitmasks combinatorics dp | Statement | F1 | Educational Codeforces Round 186 (Rated for Div. 2) {2182} | PROGRAMMING | Educational Codeforces Round 186 Editorial | ||
| 1169 | Christmas Reindeer (hard version) | bitmasks combinatorics dp | Statement | F2 | Educational Codeforces Round 186 (Rated for Div. 2) {2182} | PROGRAMMING | Educational Codeforces Round 186 Editorial | ||
| 723 | 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 | |
| 5726 | 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 | |
| 14896 | 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 | |
| 6600 | 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 | |
| 103 | Xor Product | bitmasks dp | Statement | F | Codeforces Round 1073 (Div. 1) {2190} | PROGRAMMING | 3500.0 | Codeforces Round 1073 (Div. 1, Div. 2) Editorial | |
| 233 | 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 | |
| 1001 | Again Trees... (Easy Version) | bitmasks dfs and similar dp fft trees | Statement | F1 | Codeforces Round 1078 (Div. 2) {2194} | PROGRAMMING | 1750.0 | Codeforces Round #1078 Editorial | |
| 11832 | 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 | |
| 8141 | Test Generator | binary search bitmasks greedy math | Statement | C | Educational Codeforces Round 187 (Rated for Div. 2) {2203} | PROGRAMMING | Educational Codeforces Round 187 Editorial | ||
| 239 | Simons and Diophantus Equation | bitmasks brute force data structures number theory | Statement | G | Codeforces Round 1083 (Div. 2) {2205} | PROGRAMMING | 3250.0 | Tutorial | |
| 3371 | 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 | |
| 174 | EXPloration, EXPloitation, and Gain Some EXPerience! | bitmasks brute force dp greedy implementation | Statement | D | Codeforces Round 1092 (Unrated, Div. 1, Based on THUPC 2026 — Finals) {2215} | PROGRAMMING | 2750.0 | 152930 | |
| 889 | 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 | |
| 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 | |
| 17737 | The 67th XOR Problem | binary search bitmasks brute force trees | Statement | E | Codeforces Round 1090 (Div. 4) {2218} | PROGRAMMING | Codeforces Round 1090 (Div. 4) Editorial | ||
| 2425 | 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 | |
| 8549 | Exceptional Segments | bitmasks brute force math | Statement | D | Educational Codeforces Round 189 (Rated for Div. 2) {2225} | PROGRAMMING | Tutorial | ||
| 1138 | Load Unbalancing | binary search bitmasks dp greedy implementation | Statement | F | Spectral::Cup 2026 Round 2 (Codeforces Round 1100, Div. 1 + Div. 2) {2229} | PROGRAMMING | 2500.0 | Spectral::Cup 2026 Round 2 (Codeforces Round 1100, Div. 1 + Div. 2) Editorial | |
| 8973 | XOR, Expression and Two Binary Numbers | bitmasks constructive algorithms math number theory | Statement | D | Codeforces Round 1102 (Div. 2) {2234} | PROGRAMMING | 1750.0 | Tutorial | |
| 9346 | 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 | |
| 1547 | 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 | ||
| 6851 | 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 | |
| 3204 | diss_quack and Array Game | bitmasks brute force games greedy | Statement | D | Codeforces Round 1108 (Div. 2) {2246} | PROGRAMMING | 1750.0 | Codeforces Round 1108 (Div. 2) Editorial | |
| 642 | lce4113 and Security Game | bitmasks interactive probabilities | Statement | E | Codeforces Round 1108 (Div. 2) {2246} | PROGRAMMING | 2250.0 | Codeforces Round 1108 (Div. 2) Editorial | |
| 6586 | XOR Sorting (Easy Version) | binary search bitmasks divide and conquer greedy | Statement | D1 | Codeforces Round 1111 (Div. 2) {2247} | PROGRAMMING | 1500.0 | ||
| 2393 | XOR Sorting (Hard Version) | bitmasks data structures greedy | Statement | D2 | Codeforces Round 1111 (Div. 2) {2247} | PROGRAMMING | 1250.0 | ||
| 1068 | 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 | |
| 1521 | Generational Triplets | bitmasks combinatorics dp math | Statement | E | Codeforces Round 1115 (Div. 2) {2252} | PROGRAMMING | 2250.0 | 155741 | |
| 370 | 4-beauty | bitmasks dp graphs math | Statement | F | Educational Codeforces Round 193 (Rated for Div. 2) {2253} | PROGRAMMING | 155813 | ||
| 3060 | Whiplash | bitmasks constructive algorithms math | Statement | F | Codeforces Round 1114 (Div. 3) {2254} | PROGRAMMING | Tutorial | ||
| 1388 | How Long Until Nothing Remains? | binary search bitmasks greedy | Statement | D | Codeforces Round 1116 (Div. 1) {2255} | PROGRAMMING | 1750.0 | 155840 |