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Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 370 | 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 | |
| 1685 | Table | bitmasks combinatorics dp math | Statement | B | Codeforces Round 144 (Div. 1) {232} | PROGRAMMING | Editorial for Codeforces Round #144 | 2200 | |
| 16576 | 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 | |
| 1268 | Captains Mode | bitmasks dp games | Statement | C | Codeforces Round 222 (Div. 1) {377} | PROGRAMMING | Codeforces Round #222 — Problem Analysis | 2400 | |
| 4615 | 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 | |
| 2901 | Random Task | binary search bitmasks combinatorics dp math | Statement | D | Codeforces Round 247 (Div. 2) {431} | PROGRAMMING | Editorial Codeforces Round #247 (Div. 2) | 2200 | |
| 824 | Valera and Number | bitmasks dp math probabilities | Statement | E | Codeforces Round 252 (Div. 2) {441} | PROGRAMMING | Разбор Codeforces Round #252 (Div. 2) | 2700 | |
| 37470 | Dreamoon and WiFi | bitmasks brute force combinatorics dp math probabilities | Statement | B | Codeforces Round 272 (Div. 2) {476} | PROGRAMMING | 1300 | ||
| 6463 | Fox And Jumping | bitmasks brute force dp math | Statement | D | Codeforces Round 290 (Div. 2) {510} | PROGRAMMING | Codeforces Round #290 Editorial | 2100 | |
| 4236 | 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 | |
| 3448 | Mike and Foam | bitmasks combinatorics dp math number theory | Statement | C | Codeforces Round 305 (Div. 1) {547} | PROGRAMMING | Codeforces Round #305 Editorial | 2700 | |
| 2466 | 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 | |
| 1446 | LRU | bitmasks dp math probabilities | Statement | C | Codeforces Round 363 (Div. 1) {698} | PROGRAMMING | Solution | 2700 | |
| 3521 | 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 | |
| 7473 | Square Subsets | bitmasks combinatorics dp math | Statement | C | Codeforces Round 448 (Div. 2) {895} | PROGRAMMING | Codeforces Round #448(Div.2) Editorial | 2000 | |
| 3833 | Unusual Sequences | bitmasks combinatorics dp math number theory | Statement | D | Codeforces Round 450 (Div. 2) {900} | PROGRAMMING | Codeforces Round #450(Div. 2). Editorial. | 2100 | |
| 840 | New Year and Entity Enumeration | bitmasks combinatorics dp math | Statement | E | Good Bye 2017 {908} | PROGRAMMING | Good Bye 2017 Editorial | 2400 | |
| 1148 | 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 | |
| 3778 | 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 | |
| 2888 | 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 | |
| 2210 | 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 |
| 757 | Little C Loves 3 III | bitmasks dp math | Statement | E | Codeforces Round 511 (Div. 1) {1034} | PROGRAMMING | Codeforces Round #511 Editorial | 3200 | |
| 1106 | Maximum Matching | bitmasks brute force dfs and similar dp graphs | Statement | E | Codeforces Round 508 (Div. 2) {1038} | PROGRAMMING | Tutorial | 2400 | |
| 3035 | 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 | |
| 3657 | Segment Sum | bitmasks combinatorics dp math | Statement | E | Educational Codeforces Round 53 (Rated for Div. 2) {1073} | PROGRAMMING | 62742 | 2300 | |
| 140 | Mateusz and an Infinite Sequence | bitmasks brute force dp strings | Statement | H | Hello 2019 {1097} | PROGRAMMING | 64310 | 3000 | |
| 530 | 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 |
| 687 | Wise Men (Hard Version) | bitmasks dp math | Statement | F2 | Codeforces Global Round 7 {1326} | PROGRAMMING | 1500.0 | 74961 | 3200 |
| 7166 | 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 |
| 5539 | GameGame | bitmasks constructive algorithms dp games greedy math | Statement | B | Codeforces Round 659 (Div. 1) {1383} | PROGRAMMING | 1000.0 | Codeforces Round #659 Editorial | |
| 683 | Omkar and Pies | bitmasks dfs and similar dp math | Statement | G | Codeforces Global Round 10 {1392} | PROGRAMMING | 3000.0 | Codeforces Global Round 10 — Editorial | |
| 883 | 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 | ||
| 4474 | 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 | |
| 14284 | Baby Ehab Partitions Again | bitmasks constructive algorithms dp math | Statement | C | Codeforces Round 717 (Div. 2) {1516} | PROGRAMMING | 1500.0 | Codeforces round #717 editorial | |
| 7924 | Array Differentiation | bitmasks dp graphs math | Statement | D | Codeforces Global Round 15 {1552} | PROGRAMMING | 1000.0 | Editorial of Global Round 15 | |
| 1429 | 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 |
| 10737 | Moamen and XOR | bitmasks combinatorics dp math | Statement | C | Codeforces Round 737 (Div. 2) {1557} | PROGRAMMING | 1750.0 | Codeforces Round #737 Editorial | |
| 11357 | Divan and bitwise operations | bitmasks combinatorics constructive algorithms dp math | Statement | C | Codeforces Round 757 (Div. 2) {1614} | PROGRAMMING | 1500.0 | Tutorial | 1500 |
| 1249 | 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 |
| 7300 | BA-String | bitmasks brute force dp greedy implementation math shortest paths | Statement | C | Educational Codeforces Round 119 (Rated for Div. 2) {1620} | PROGRAMMING | 98061 | ||
| 1168 | Subsequences Galore | bitmasks combinatorics dp math | Statement | G | Educational Codeforces Round 119 (Rated for Div. 2) {1620} | PROGRAMMING | 98061 | ||
| 777 | Formalism for Formalism | bitmasks dp math | Statement | F | Codeforces Round 791 (Div. 2) {1679} | PROGRAMMING | 3000.0 | Codeforces Round #791 (Div. 2) Editorial | |
| 12878 | Good Key, Bad Key | bitmasks brute force dp greedy math | Statement | G | Codeforces Round 806 (Div. 4) {1703} | PROGRAMMING | 104786 | ||
| 692 | 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 |
| 978 | 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 | |
| 305 | Antifibonacci Cut | bitmasks combinatorics dp math | Statement | G | Educational Codeforces Round 137 (Rated for Div. 2) {1743} | PROGRAMMING | Educational Codeforces Round 137 Editorial | 3000 | |
| 7492 | 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 | |
| 2798 | 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 | |
| 560 | 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 | ||
| 1509 | XOR Counting | bitmasks combinatorics dp math | Statement | D | Codeforces Round 865 (Div. 1) {1815} | PROGRAMMING | 2500.0 | Editorial of Codeforces Round #865 | 2600 |
| 11050 | Don't Blame Me | bitmasks combinatorics dp math | Statement | H | Codeforces Round 871 (Div. 4) {1829} | PROGRAMMING | Codeforces Round 871 (Div. 4) Editorial | 1700 | |
| 2776 | 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 | |
| 1399 | 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 | |
| 16965 | XOR-distance | bitmasks dp greedy implementation math | Statement | C | Codeforces Round 922 (Div. 2) {1918} | PROGRAMMING | 1250.0 | Codeforces Round #922 (Div. 2) Editorial | |
| 15002 | 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 | ||
| 5892 | 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 |
| 2265 | Fenwick Tree | bitmasks brute force combinatorics data structures dp math trees | Statement | C | Codeforces Round 942 (Div. 1) {1967} | PROGRAMMING | 1250.0 | Tutorial | 2300 |
| 1051 | 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 |
| 1916 | 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 | |
| 1637 | Minecraft | bitmasks brute force dp math | Statement | G | Codeforces Round 959 sponsored by NEAR (Div. 1 + Div. 2) {1994} | PROGRAMMING | 2750.0 | Video Tutorial | |
| 4036 | 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 | |
| 111 | Bit Game (Hard Version) | bitmasks dp math | Statement | E2 | Codeforces Round 982 (Div. 2) {2027} | PROGRAMMING | 1000.0 | Codeforces Round #982 (Div. 2) Editorial | |
| 553 | 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 | |
| 12470 | 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 | |
| 450 | 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 | |
| 2544 | Bitwise Slides | bitmasks combinatorics dp math | Statement | C | Codeforces Round 1004 (Div. 1) {2066} | PROGRAMMING | 1250.0 | 139415 | |
| 1113 | 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 | |
| 6776 | Infinite Sequence (Easy Version) | bitmasks dp math | Statement | D1 | Codeforces Round 1007 (Div. 2) {2071} | PROGRAMMING | 1750.0 | Codeforces Round 1007 (Div. 2) Editorial | |
| 5912 | Equalization | bitmasks brute force dp greedy math | Statement | D | Educational Codeforces Round 176 (Rated for Div. 2) {2075} | PROGRAMMING | Educational Codeforces Round 176 Editorial | ||
| 4157 | 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 | |
| 1686 | 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 | ||
| 229 | 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 | |
| 5560 | 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 | ||
| 2057 | Build an Array | bitmasks dp math number theory | Statement | G | Codeforces Round 1027 (Div. 3) {2114} | PROGRAMMING | 143268 | ||
| 1733 | 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 | |
| 3839 | Wafu! | bitmasks brute force dp math | Statement | G | Codeforces Round 1042 (Div. 3) {2131} | PROGRAMMING | Codeforces Round 1042 (Div. 3) Editorial | ||
| 3746 | Taiga's Carry Chains | bitmasks brute force dp greedy | Statement | D | Codeforces Round 1068 (Div. 2) {2173} | PROGRAMMING | 1750.0 | ||
| 1532 | Omega Numbers | bitmasks dp math number theory | Statement | F | Codeforces Round 1070 (Div. 2) {2176} | PROGRAMMING | 2750.0 | Codeforces Round 1070 (Div.2) Editorial | |
| 1332 | Blackslex and Plants | bitmasks data structures dp math | Statement | H | Codeforces Round 1071 (Div. 3) {2179} | PROGRAMMING | Codeforces Round 1071 (Div. 3) Editorial | ||
| 6578 | 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 | |
| 679 | 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 | |
| 840 | Interval Game | bitmasks combinatorics dp games greedy math probabilities | Statement | F | Codeforces Round 1091 (Div. 2) and CodeCraft 26 {2217} | PROGRAMMING | 2750.0 | Tutorial |