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Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 1084 | Ladies' Shop | constructive algorithms fft math | Statement | E | Codeforces Round 176 (Div. 1) {286} | PROGRAMMING | Tutorial | 2600 | |
| 735 | Kyoya and Train | dp fft graphs math probabilities | Statement | E | Codeforces Round 309 (Div. 1) {553} | PROGRAMMING | Codeforces Round #309 Editorial | 3300 | |
| 726 | Transforming Sequence | combinatorics dp fft math | Statement | E | AIM Tech Round (Div. 1) {623} | PROGRAMMING | AIM Tech Round Tutorial | 3300 | |
| 3693 | Thief in a Shop | divide and conquer dp fft math | Statement | E | Educational Codeforces Round 9 {632} | PROGRAMMING | 43493 | 2500 | |
| 2635 | 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 | |
| 728 | Complete the Permutations | combinatorics fft graphs math | Statement | E | Codeforces Round 372 (Div. 1) {715} | PROGRAMMING | Codeforces Round #372 Editorial | 3400 | |
| 1149 | PolandBall and Many Other Balls | combinatorics divide and conquer dp fft math number theory | Statement | G | 8VC Venture Cup 2017 - Elimination Round {755} | PROGRAMMING | 8VC Venture Cup 2017 — Elimination Round [Editorial] | 3100 | |
| 396 | Test Data Generation | combinatorics divide and conquer dp fft math number theory | Statement | F | VK Cup 2017 - Round 3 {773} | PROGRAMMING | VK Cup 2017 Round 3 + Codeforces Round #412 -- Tutorial | 3400 | |
| 1301 | Rusty String | fft math strings | Statement | E | Codeforces Round 423 (Div. 1, rated, based on VK Cup Finals) {827} | PROGRAMMING | Codeforces Round #423 Analysis | 2700 | |
| 314 | Days of Floral Colours | combinatorics divide and conquer dp fft math | Statement | E | Codeforces Round 431 (Div. 1) {848} | PROGRAMMING | Codeforces Round #431 Editorial | 3400 | |
| 577 | 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 | |
| 107 | Cyclic Cipher | fft math | Statement | E | Codeforces Round 453 (Div. 1) {901} | PROGRAMMING | Codeforces Round #453 (Div. 1 & Div. 2) Editorial | 3300 | |
| 1270 | 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 | |
| 643 | Perpetual Subtraction | fft math matrices | Statement | E | VK Cup 2018 - Round 1 {923} | PROGRAMMING | VK Cup 2018 Round 1 and CF Round #470 (div. 1 & 2) editorial | 3100 | |
| 1413 | Yet Another String Matching Problem | fft math | Statement | I | Educational Codeforces Round 40 (Rated for Div. 2) {954} | PROGRAMMING | 58519 | 2600 | |
| 1292 | Bandit Blues | combinatorics dp fft math | Statement | G | Divide by Zero 2018 and Codeforces Round 474 (Div. 1 + Div. 2, combined) {960} | PROGRAMMING | Divide by Zero 2018 and Codeforces Round #474 (Div. 1 + Div. 2, combined) Editorial | 2800 | |
| 502 | K Paths | combinatorics data structures dp fft math | Statement | H | Avito Code Challenge 2018 {981} | PROGRAMMING | Avito Code Challenge 2018 — разбор | 2900 | |
| 399 | Perfect Encoding | fft math | Statement | D | Codeforces Round 485 (Div. 1) {986} | PROGRAMMING | Codeforces Round #485 Editorial | 2600 | |
| 1891 | Nikita and Order Statistics | chinese remainder theorem fft math | Statement | E | Codeforces Round 488 by NEAR (Div. 1) {993} | PROGRAMMING | Codeforces Round #488 editorial | 2300 | |
| 512 | 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 | |
| 331 | Epic Convolution | chinese remainder theorem fft math number theory | Statement | H | Mail.Ru Cup 2018 Round 1 {1054} | PROGRAMMING | Editorial | 3400 | |
| 411 | Radix sum | fft math number theory | Statement | E | Codeforces Round 534 (Div. 1) {1103} | PROGRAMMING | Codeforces Round #534 — Editorial | 3300 | |
| 972 | Triple | fft math | Statement | H | Codeforces Global Round 2 {1119} | PROGRAMMING | Codeforces Global Round 2 Editorial | 3100 | |
| 177 | Heidi Learns Hashing (Hard) | fft math number theory | Statement | A3 | Helvetic Coding Contest 2019 online mirror (teams allowed, unrated) {1184} | PROGRAMMING | helvetic-coding-contest-2019-editorial.pdf | 3100 | |
| 799 | Divisor Set | divide and conquer fft greedy math number theory | Statement | G | Educational Codeforces Round 76 (Rated for Div. 2) {1257} | PROGRAMMING | Educational Codeforces Round 76 Editorial | 2700 | |
| 417 | Xor on Figures | constructive algorithms fft math | Statement | I | Good Bye 2019 {1270} | PROGRAMMING | Разбор Goodbye 2019 | 3400 | |
| 540 | Harry The Potter | brute force constructive algorithms dp fft implementation math | Statement | F | Codeforces Round 612 (Div. 1) {1286} | PROGRAMMING | Codeforces Round #612 - Editorial | 3200 | |
| 3729 | Placing Rooks | combinatorics fft math | Statement | E | Educational Codeforces Round 86 (Rated for Div. 2) {1342} | PROGRAMMING | 76633 | 2300 | |
| 674 | Slime and Sequences (Easy Version) | dp fft math | Statement | F1 | Codeforces Round 641 (Div. 1) {1349} | PROGRAMMING | 1750.0 | Codeforces Round #641 Editorial | 3100 |
| 142 | Slime and Sequences (Hard Version) | dp fft math | Statement | F2 | Codeforces Round 641 (Div. 1) {1349} | PROGRAMMING | 1750.0 | Codeforces Round #641 Editorial | 3500 |
| 336 | Kevin and Grid | fft graphs math | Statement | I | Codeforces Global Round 10 {1392} | PROGRAMMING | 4000.0 | Codeforces Global Round 10 — Editorial | |
| 1336 | Running Competition | bitmasks fft math number theory | Statement | G | Educational Codeforces Round 93 (Rated for Div. 2) {1398} | PROGRAMMING | Educational Codeforces Round 93 Editorial | ||
| 649 | Multithreading (Easy Version) | combinatorics fft math | Statement | H1 | Codeforces Global Round 12 {1450} | PROGRAMMING | 2750.0 | Codeforces Global Round 12 Editorial | |
| 509 | Tiles | combinatorics dp fft math | Statement | G | Educational Codeforces Round 102 (Rated for Div. 2) {1473} | PROGRAMMING | Educational Codeforces Round 102 Editorial | ||
| 384 | Nezzar and Chocolate Bars | combinatorics fft math probabilities | Statement | F | Codeforces Round 698 (Div. 1) {1477} | PROGRAMMING | 4000.0 | 87294 | 3500 |
| 471 | School Clubs | dp fft math number theory probabilities | Statement | E | Codeforces Round 700 (Div. 1) {1479} | PROGRAMMING | 4000.0 | Editorial of Codeforces Round #700 | |
| 43 | Flower Shop | *special fft math | Statement | J | Kotlin Heroes: Episode 6 {1488} | PROGRAMMING | 88522 | ||
| 556 | AmShZ Farm | combinatorics fft math | Statement | F | Codeforces Round 722 (Div. 1) {1528} | PROGRAMMING | 3000.0 | Codeforces Round #722 Editorial | |
| 1483 | Abnormal Permutation Pairs (easy version) | combinatorics dp fft math | Statement | E1 | Codeforces Round 729 (Div. 2) {1542} | PROGRAMMING | 2000.0 | ||
| 2121 | The Three Little Pigs | combinatorics dp fft math | Statement | C | Codeforces Round 736 (Div. 1) {1548} | PROGRAMMING | 1750.0 | Codeforces Round 736 Editorial | |
| 389 | Stairs | combinatorics divide and conquer fft math | Statement | I | Harbour.Space Scholarship Contest 2021-2022 (open for everyone, rated, Div. 1 + Div. 2) {1553} | PROGRAMMING | 5250.0 | Harbour.Space Scholarship Contest 2021-2022 (Div. 1 + Div. 2) Editorial | |
| 2800 | Mocha and Stars | combinatorics dp fft math number theory | Statement | E | Codeforces Round 738 (Div. 2) {1559} | PROGRAMMING | 3000.0 | Tutorial (en) | 2200 |
| 255 | Problems for Codeforces | fft math | Statement | F | Codeforces Round 745 (Div. 1) {1580} | PROGRAMMING | 3500.0 | Codeforces Round #745 Editorial | 3300 |
| 1624 | Dominoes | combinatorics fft graphs math | Statement | D | Codeforces Round 758 (Div.1 + Div. 2) {1608} | PROGRAMMING | 1500.0 | Editorial of Codeforces Round #758 (Div.1 + Div. 2) | |
| 526 | Basis | combinatorics fft math number theory | Statement | F | Educational Codeforces Round 123 (Rated for Div. 2) {1644} | PROGRAMMING | 100227 | ||
| 111 | Three Minimums | combinatorics fft math | Statement | H | Codeforces Round 778 (Div. 1 + Div. 2, based on Technocup 2022 Final Round) {1654} | PROGRAMMING | 4000.0 | Editorial of Codeforces Round #778 (Div. 1 + Div. 2, based on Technocup 2022 Final Round) | 3500 |
| 954 | Centroid Probabilities | combinatorics dp fft math | Statement | E | Codeforces Round 783 (Div. 1) {1667} | PROGRAMMING | 2750.0 | Codeforces Round #783 Editorial | 3000 |
| 515 | Permutation Counting | brute force combinatorics dp fft math | Statement | F | Educational Codeforces Round 127 (Rated for Div. 2) {1671} | PROGRAMMING | 102181 | ||
| 113 | Koishi's Unconscious Permutation | fft math | Statement | F | Codeforces Round 796 (Div. 1) {1687} | PROGRAMMING | 3000.0 | Editorial of Codeforces Round 796 | |
| 399 | Game of AI (easy version) | combinatorics fft math | Statement | H1 | CodeTON Round 2 (Div. 1 + Div. 2, Rated, Prizes!) {1704} | PROGRAMMING | 2250.0 | CodeTON Round 2 Editorial | |
| 119 | Game of AI (hard version) | combinatorics fft math | Statement | H2 | CodeTON Round 2 (Div. 1 + Div. 2, Rated, Prizes!) {1704} | PROGRAMMING | 2750.0 | CodeTON Round 2 Editorial | |
| 183 | Mio and Lucky Array | constructive algorithms fft math strings | Statement | G | CodeTON Round 2 (Div. 1 + Div. 2, Rated, Prizes!) {1704} | PROGRAMMING | 3500.0 | CodeTON Round 2 Editorial | |
| 729 | Multiset of Strings | dp fft flows graphs greedy math | Statement | F | Educational Codeforces Round 132 (Rated for Div. 2) {1709} | PROGRAMMING | 105164 | ||
| 1771 | Almost Perfect | combinatorics fft math | Statement | E | Codeforces Round 819 (Div. 1 + Div. 2) and Grimoire of Code Annual Contest 2022 {1726} | PROGRAMMING | 2250.0 | Codeforces Round #819 (Div. 1 + Div. 2) and Grimoire of Code Annual Contest 2022 Editorial | |
| 924 | Function Sum | brute force combinatorics dp fft math | Statement | F | Codeforces Round 841 (Div. 2) and Divide by Zero 2022 {1731} | PROGRAMMING | 2750.0 | Codeforces Round #841 (Div. 2) and Divide By Zero 2022 Editorial | |
| 2369 | Partial Sorting | combinatorics fft math number theory | Statement | E | Codeforces Round 842 (Div. 2) {1768} | PROGRAMMING | 2250.0 | Codeforces Round #842 (Div. 2) Editorial | |
| 196 | Koxia and Bracket | divide and conquer fft math | Statement | G | Good Bye 2022: 2023 is NEAR {1770} | PROGRAMMING | 3250.0 | Good Bye 2022 -- Editorial | |
| 921 | Laboratory on Pluto | brute force combinatorics dp fft greedy math | Statement | F | Codeforces Round 843 (Div. 2) {1775} | PROGRAMMING | 3000.0 | Codeforces Round #843 (Div. 2) Editorial | |
| 1015 | Timber | combinatorics dp fft math | Statement | F | Educational Codeforces Round 147 (Rated for Div. 2) {1821} | PROGRAMMING | 115296 | ||
| 502 | Swimmers in the Pool | fft math number theory | Statement | F | Educational Codeforces Round 151 (Rated for Div. 2) {1845} | PROGRAMMING | 117791 | ||
| 207 | Cyclic Hamming (Easy Version) | divide and conquer dp fft math number theory | Statement | H1 | CodeTON Round 7 (Div. 1 + Div. 2, Rated, Prizes!) {1896} | PROGRAMMING | 4000.0 | CodeTON Round 7 (Div. 1 + Div. 2, Rated, Prizes!) Editorial | |
| 170 | Cyclic Hamming (Hard Version) | dp fft math number theory | Statement | H2 | CodeTON Round 7 (Div. 1 + Div. 2, Rated, Prizes!) {1896} | PROGRAMMING | 1000.0 | CodeTON Round 7 (Div. 1 + Div. 2, Rated, Prizes!) Editorial | |
| 183 | Short Permutation Problem | combinatorics dp fft math | Statement | I | Pinely Round 3 (Div. 1 + Div. 2) {1909} | PROGRAMMING | 6000.0 | Editorial of Pinely Round 3 (Div. 1 + Div. 2) | |
| 1467 | Blueprint for Seating | combinatorics divide and conquer fft math | Statement | B | 2023-2024 ICPC, NERC, Northern Eurasia Onsite (Unrated, Online Mirror, ICPC Rules, Teams Preferred) {1912} | PROGRAMMING | Tutorials (PDF) | 2000 | |
| 161 | Yet Yet Another Permutation Problem | divide and conquer fft math | Statement | E | Codeforces Round 930 (Div. 1) {1936} | PROGRAMMING | 2500.0 | Codeforces Round 930 (Div. 1, Div. 2) Editorial | |
| 474 | Again Counting Arrays (Easy Version) | combinatorics dp fft math | Statement | E1 | Codeforces Round 942 (Div. 1) {1967} | PROGRAMMING | 1750.0 | Tutorial | 3100 |
| 357 | Zimpha Fan Club | fft greedy math strings | Statement | G | Codeforces Round 947 (Div. 1 + Div. 2) {1975} | PROGRAMMING | 3000.0 | editorial_zh.pdf | 3000 |
| 485 | Heartbeat | combinatorics dp fft math | Statement | F | Codeforces Round 958 (Div. 2) {1988} | PROGRAMMING | 3500.0 | Editorial of Codeforces Round 958 (Div. 2) | |
| 584 | Prime Split Game | fft games math number theory | Statement | H | Pinely Round 4 (Div. 1 + Div. 2) {1991} | PROGRAMMING | 3500.0 | Video Tutorial | |
| 2400 | Card Game | combinatorics dp fft greedy math | Statement | E | Educational Codeforces Round 170 (Rated for Div. 2) {2025} | PROGRAMMING | Educational Codeforces Round 170 Editorial | ||
| 14777 | Sakurako, Kosuke, and the Permutation | brute force data structures dfs and similar dsu fft greedy math | Statement | E | Codeforces Round 981 (Div. 3) {2033} | PROGRAMMING | 135520 | ||
| 495 | Alternative Platforms | combinatorics data structures fft math sortings | Statement | F | 2024-2025 ICPC, NERC, Southern and Volga Russian Regional Contest (Unrated, Online Mirror, ICPC Rules, Preferably Teams) {2038} | PROGRAMMING | 2500 | ||
| 68 | Kevin and Puzzle (Hard Version) | bitmasks fft math | Statement | I2 | Codeforces Global Round 28 {2048} | PROGRAMMING | 3000.0 | Tutorial | |
| 2423 | Binary Subsequence Value Sum | combinatorics dp fft implementation math | Statement | C | Codeforces Round 1008 (Div. 1) {2077} | PROGRAMMING | 1500.0 | Codeforces Round 1008 (Div. 1, Div. 2) Editorial | |
| 1829 | Blossom | combinatorics fft math | Statement | E | Teza Round 1 (Codeforces Round 1015, Div. 1 + Div. 2) {2084} | PROGRAMMING | 2250.0 | 141155 | |
| 852 | Blurry Vision | *special fft math | Statement | H | April Fools Day Contest 2025 {2095} | PROGRAMMING | April Fools Day Contest 2025 Editorial | ||
| 236 | 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 | |
| 642 | Cost of Coloring | combinatorics fft math | Statement | G | Educational Codeforces Round 183 (Rated for Div. 2) {2145} | PROGRAMMING | Educational Codeforces Round 183 Editorial | ||
| 354 | Subsequence Problem | combinatorics dp fft math | Statement | F | Educational Codeforces Round 184 (Rated for Div. 2) {2169} | PROGRAMMING | Educational Codeforces Round 184 Editorial | ||
| 508 | Mosaic Tree | combinatorics dp fft math trees | Statement | F | Codeforces Round 1069 (Div. 1) {2174} | PROGRAMMING | 3500.0 | Codeforces Round 1069 Editorial | |
| 301 | ABBA Counting | fft math number theory strings | Statement | E | Codeforces Round 1082 (Div. 1) {2201} | PROGRAMMING | 3000.0 | Codeforces Round 1082 (Div. 1, Div. 2) Complete Editorial | |
| 110 | Zhily and Colorful Strings | divide and conquer fft math | Statement | F | Codeforces Round 1097 (Div. 1, Based on Zhili Cup 2026) {2223} | PROGRAMMING | 4500.0 | Codeforces Round 1097 (Div. 1, Div2, Based on Zhili Cup 2026) Tutorial | |
| 990 | Elections in Saransk (hard version) | combinatorics dp fft math number theory | Statement | F2 | Codeforces Round 1103 (Div. 3) {2236} | PROGRAMMING | 154496 |