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Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 1185 | Interestring graph and Apples | dfs and similar dsu graphs | Statement | E | Codeforces Beta Round 9 (Div. 2 Only) {9} | PROGRAMMING | Codeforces Beta Round #9 tutorial | 2300 | |
| 3157 | Ring Road 2 | 2-sat dfs and similar dsu graphs | Statement | D | Codeforces Beta Round 27 (Codeforces format, Div. 2) {27} | PROGRAMMING | Solution of ABC @ Round#27 | 2300 | |
| 5660 | pSort | dfs and similar dsu graphs | Statement | B | Codeforces Beta Round 28 (Codeforces format) {28} | PROGRAMMING | Codeforces Beta Round #28 (Разбор задач A и B) | 1600 | |
| 1439 | Chessboard Billiard | dfs and similar dsu graphs number theory | Statement | C | Codeforces Beta Round 68 {74} | PROGRAMMING | Solutions for Codeforces Beta Round #68 | 2100 | |
| 430 | Pairs | dfs and similar dp dsu graphs implementation trees | Statement | E | Yandex.Algorithm Open 2011: Qualification 1 {81} | PROGRAMMING | 2600 | ||
| 1086 | Beautiful Road | dfs and similar dp dsu graphs implementation sortings trees | Statement | D | Codeforces Beta Round 73 (Div. 1 Only) {87} | PROGRAMMING | CodeForces Beta Round #73 div. 1 analysis (particulary with div. 2) | 2300 | |
| 448 | Leaders | dfs and similar dsu graphs trees | Statement | E | Yandex.Algorithm 2011: Finals {97} | PROGRAMMING | Финал Яндекс.Алгоритм: разбор A-B | 2800 | |
| 10974 | Cthulhu | dfs and similar dsu graphs | Statement | B | Codeforces Beta Round 80 (Div. 1 Only) {103} | PROGRAMMING | Tutorial | 1600 | |
| 3449 | Edges in MST | dfs and similar dsu graphs sortings | Statement | D | Codeforces Round 111 (Div. 2) {160} | PROGRAMMING | Codeforces Round #111 (Div. 2) Разбор Задач | 2500 | |
| 3064 | Party | brute force dfs and similar dsu graphs | Statement | C2 | ABBYY Cup 2.0 - Easy {177} | PROGRAMMING | 1500 | ||
| 3040 | Party | dfs and similar dsu graphs | Statement | C1 | ABBYY Cup 2.0 - Easy {177} | PROGRAMMING | 1500 | ||
| 24922 | Ice Skating | brute force dfs and similar dsu graphs | Statement | A | Codeforces Round 134 (Div. 1) {217} | PROGRAMMING | Editorial for Codeforces Round #134 | 1400 | |
| 2862 | The Road to Berland is Paved With Good Intentions | 2-sat dfs and similar dsu graphs | Statement | E | Codeforces Round 141 (Div. 2) {228} | PROGRAMMING | Codeforces Round #141 (Div. 2) Tutorial | 2000 | |
| 993 | The Red Button | combinatorics dfs and similar dsu graphs greedy | Statement | E | MemSQL start[c]up Round 1 {325} | PROGRAMMING | Editorial | 2700 | |
| 1092 | Fools and Foolproof Roads | data structures dfs and similar dsu graphs greedy | Statement | D | Codeforces Round 212 (Div. 2) {362} | PROGRAMMING | Codeforces Round #212 (Div. 2). Tutorial. Part 1. | 2500 | |
| 2684 | Information Graph | dfs and similar dsu graphs trees | Statement | E | Codeforces Round 266 (Div. 2) {466} | PROGRAMMING | Editorial Codeforces Round #266 (Div. 2) | 2400 | |
| 9688 | New Year Permutation | dfs and similar dsu graphs greedy math sortings | Statement | B | Good Bye 2014 {500} | PROGRAMMING | Tutorial 2 | 1600 | |
| 15129 | Mr. Kitayuta's Colorful Graph | dfs and similar dp dsu graphs | Statement | B | Codeforces Round 286 (Div. 2) {505} | PROGRAMMING | Tutorial | 1500 | |
| 2585 | Mr. Kitayuta's Colorful Graph | brute force dfs and similar dsu graphs | Statement | D | Codeforces Round 286 (Div. 1) {506} | PROGRAMMING | Editorial | 2300 | |
| 1987 | Love Triangles | dfs and similar dsu graphs | Statement | C | Codeforces Round 309 (Div. 1) {553} | PROGRAMMING | Codeforces Round #309 Editorial | 2300 | |
| 10657 | Minimum spanning tree for each edge | data structures dfs and similar dsu graphs trees | Statement | E | Educational Codeforces Round 3 {609} | PROGRAMMING | Editorial | 2100 | |
| 271 | Island Puzzle | dfs and similar dsu graphs trees | Statement | F | 8VC Venture Cup 2016 - Final Round {627} | PROGRAMMING | 8VC Venture Cup 2016 — Final Round Editorial | 3400 | |
| 2228 | Table Compression | dfs and similar dp dsu graphs greedy | Statement | C | Codeforces Round 345 (Div. 1) {650} | PROGRAMMING | Codeforces Round #345: editorial | 2300 | |
| 2971 | Pursuit For Artifacts | dfs and similar dsu graphs trees | Statement | E | Educational Codeforces Round 10 {652} | PROGRAMMING | Editorial of Educational Codeforces Round 10 | 2300 | |
| 1763 | Bear and Forgotten Tree 2 | dfs and similar dsu graphs trees | Statement | E | IndiaHacks 2016 - Online Edition (Div. 1 + Div. 2) {653} | PROGRAMMING | IndiaHacks Finals 2016 — Editorial | 2400 | |
| 8066 | New Reform | data structures dfs and similar dsu graphs greedy | Statement | E | Codeforces Round 346 (Div. 2) {659} | PROGRAMMING | Editorial for Codeforces Round #346 (Div. 2) | 1600 | |
| 1992 | Polycarp and Hay | dfs and similar dsu graphs greedy sortings | Statement | F | Codeforces Round 346 (Div. 2) {659} | PROGRAMMING | Editorial for Codeforces Round #346 (Div. 2) | 2100 | |
| 6243 | Fix a Tree | constructive algorithms dfs and similar dsu graphs trees | Statement | B | Codeforces Round 363 (Div. 1) {698} | PROGRAMMING | 46148 | 1700 | |
| 7575 | Lakes in Berland | dfs and similar dsu graphs greedy implementation | Statement | D | Codeforces Round 375 (Div. 2) {723} | PROGRAMMING | 1600 | ||
| 7954 | Socks | dfs and similar dsu graphs greedy | Statement | C | Codeforces Round 376 (Div. 2) {731} | PROGRAMMING | 47840 | 1600 | |
| 258 | New Year and Snowy Grid | dfs and similar dsu graphs interactive | Statement | H | Good Bye 2016 {750} | PROGRAMMING | Good Bye 2016 — hints and codes | 3400 | |
| 15334 | PolandBall and Forest | dfs and similar dsu graphs interactive trees | Statement | C | 8VC Venture Cup 2017 - Elimination Round {755} | PROGRAMMING | 8VC Venture Cup 2017 — Elimination Round [Editorial] | 1300 | |
| 12082 | Timofey and a tree | dfs and similar dp dsu graphs implementation trees | Statement | A | Codeforces Round 395 (Div. 1) {763} | PROGRAMMING | Codeforces Round #395 [Editorial] | 1600 | |
| 3993 | Mahmoud and a Dictionary | data structures dfs and similar dp dsu graphs | Statement | D | Codeforces Round 396 (Div. 2) {766} | PROGRAMMING | Codeforces round #396 editorial | 2000 | |
| 17991 | Bear and Friendship Condition | dfs and similar dsu graphs | Statement | A | VK Cup 2017 - Round 1 {771} | PROGRAMMING | VK Cup 2017 Round 1 and CF Round 405 — Editorial | 1500 | |
| 6417 | The Door Problem | 2-sat dfs and similar dsu graphs | Statement | D | ICM Technex 2017 and Codeforces Round 400 (Div. 1 + Div. 2, combined) {776} | PROGRAMMING | ICM Technex 2017 and Codeforces Round #400 (Div. 1 + Div. 2, combined) Editorial | 2000 | |
| 2936 | Weird journey | combinatorics constructive algorithms dfs and similar dsu graphs | Statement | B | Codeforces Round 407 (Div. 1) {788} | PROGRAMMING | Codeforces Round #407(Div.1 + Div.2) Editorial | 2200 | |
| 2146 | Desk Disorder | combinatorics dfs and similar dsu graphs trees | Statement | E | MemSQL Start[c]UP 3.0 - Round 1 {859} | PROGRAMMING | Tutorial | 2100 | |
| 1333 | Points, Lines and Ready-made Titles | dfs and similar dsu graphs trees | Statement | E | Technocup 2018 - Elimination Round 2 {870} | PROGRAMMING | Editorial Codeforces Round 440 Div.1+Div.2 (and Technocup 2018 — Elimination Round 2) | 2400 | |
| 1329 | Bipartite Segments | binary search data structures dfs and similar dsu graphs two pointers | Statement | C | Codeforces Round 453 (Div. 1) {901} | PROGRAMMING | Codeforces Round #453 (Div. 1 & Div. 2) Editorial | 2500 | |
| 7943 | Connected Components? | data structures dfs and similar dsu graphs | Statement | E | Educational Codeforces Round 37 (Rated for Div. 2) {920} | PROGRAMMING | T | 2100 | |
| 8286 | Love Rescue | dfs and similar dsu graphs greedy strings | Statement | D | Codeforces Round 464 (Div. 2) {939} | PROGRAMMING | Analysis of Codeforces Round #464 | 1600 | |
| 26400 | Cyclic Components | dfs and similar dsu graphs | Statement | E | Codeforces Round 479 (Div. 3) {977} | PROGRAMMING | Codeforces Round #479 (Div. 3) Editorial | 1500 | |
| 2773 | AND Graph | bitmasks dfs and similar dsu graphs | Statement | C | Codeforces Round 485 (Div. 1) {986} | PROGRAMMING | Codeforces Round #485 Editorial | 2300 | |
| 4418 | Chemical table | constructive algorithms dfs and similar dsu graphs matrices | Statement | B | Codeforces Round 500 (Div. 1) [based on EJOI] {1012} | PROGRAMMING | 60920 | 1900 | |
| 1058 | Mobile Phone Network | dfs and similar dsu graphs trees | Statement | F | Codeforces Round 504 (rated, Div. 1 + Div. 2, based on VK Cup 2018 Final) {1023} | PROGRAMMING | Codeforces Round 504 Editorial | 2600 | |
| 1994 | Session in BSU | binary search dfs and similar dsu graph matchings graphs | Statement | F | Educational Codeforces Round 49 (Rated for Div. 2) {1027} | PROGRAMMING | Educational Codeforces Round 49 Editorial | 2400 | |
| 1522 | Network Safety | dfs and similar dsu graphs math sortings | Statement | C | Codeforces Round 507 (Div. 1, based on Olympiad of Metropolises) {1039} | PROGRAMMING | 61668 | 2300 | |
| 1573 | Leaf Sets | data structures dfs and similar dsu graphs greedy sortings trees | Statement | F | Codeforces Round 510 (Div. 2) {1042} | PROGRAMMING | Tutorial | 2400 | |
| 1796 | Power Tree | dfs and similar dp dsu graphs greedy trees | Statement | D | Codeforces Round 543 (Div. 1, based on Technocup 2019 Final Round) {1120} | PROGRAMMING | Разбор задач финала Технокубка 2019 и Codeforces Round #543 | 2400 | |
| 3675 | Gourmet choice | dfs and similar dp dsu graphs greedy | Statement | D | Codeforces Round 541 (Div. 2) {1131} | PROGRAMMING | Codeforces Round #541 Editorial | 2000 | |
| 3871 | Spanning Tree with One Fixed Degree | constructive algorithms dfs and similar dsu graphs greedy | Statement | F2 | Codeforces Round 544 (Div. 3) {1133} | PROGRAMMING | Codeforces Round #544 (Div. 3) Editorial | 2200 | |
| 17307 | Edgy Trees | dfs and similar dsu graphs math trees | Statement | C | Codeforces Round 548 (Div. 2) {1139} | PROGRAMMING | Codeforces Round #548 Editorial | 1500 | |
| 27149 | News Distribution | dfs and similar dsu graphs | Statement | C | Educational Codeforces Round 65 (Rated for Div. 2) {1167} | PROGRAMMING | 67058 | 1400 | |
| 13900 | Cover it! | dfs and similar dsu graphs shortest paths trees | Statement | E | Codeforces Round 565 (Div. 3) {1176} | PROGRAMMING | 67598 | 1700 | |
| 10874 | Cow and Snacks | dfs and similar dsu graphs | Statement | D | Codeforces Round 584 - Dasha Code Championship - Elimination Round (rated, open for everyone, Div. 1 + Div. 2) {1209} | PROGRAMMING | 69791 | 1700 | |
| 3085 | Unstable String Sort | data structures dfs and similar dsu graphs greedy implementation strings | Statement | F | Codeforces Round 582 (Div. 3) {1213} | PROGRAMMING | Codeforces Round #582 (Div. 3) Editorial | 2400 | |
| 3045 | Tourism | dfs and similar dp dsu graphs greedy trees | Statement | E | Codeforces Round 586 (Div. 1 + Div. 2) {1220} | PROGRAMMING | Codeforces Round #586 Editorial | 2200 | |
| 9553 | 0-1 MST | dfs and similar dsu graphs sortings | Statement | B | Codeforces Round 599 (Div. 1) {1242} | PROGRAMMING | Codeforces Round #599 Editorial | 1900 | |
| 10365 | Harmonious Graph | constructive algorithms dfs and similar dsu graphs greedy sortings | Statement | D | Codeforces Round 600 (Div. 2) {1253} | PROGRAMMING | Editorial | 1700 | |
| 16543 | Secret Passwords | dfs and similar dsu graphs | Statement | D | Codeforces Round 603 (Div. 2) {1263} | PROGRAMMING | Codeforces Round #603 (Div. 2) Editorial | 1500 | |
| 5731 | Two Fairs | combinatorics dfs and similar dsu graphs | Statement | B | Codeforces Round 606 (Div. 1, based on Technocup 2020 Elimination Round 4) {1276} | PROGRAMMING | Technocup 2020 — Elimination Round 4 + Codeforces Round 606: Editorial | 1900 | |
| 2088 | Prefix Enlightenment | dfs and similar dsu graphs | Statement | C | Codeforces Round 616 (Div. 1) {1290} | PROGRAMMING | 1750.0 | Codeforces Round #616 Editorial | 2400 |
| 2442 | Robots on a Grid | data structures dfs and similar dsu graphs greedy matrices | Statement | F | Codeforces Round 634 (Div. 3) {1335} | PROGRAMMING | 75993 | 2600 | |
| 6394 | Monopole Magnets | constructive algorithms dfs and similar dsu graphs | Statement | B | Codeforces Round 639 (Div. 1) {1344} | PROGRAMMING | 1000.0 | Codeforces Round #639 Editorial | 2000 |
| 2110 | Johnny and Megan's Necklace | binary search bitmasks constructive algorithms dfs and similar dsu graphs | Statement | C | Codeforces Round 647 (Div. 1) - Thanks, Algo Muse! {1361} | PROGRAMMING | 2000.0 | Codeforces Round #647 Editorial | 2500 |
| 21251 | Solve The Maze | constructive algorithms dfs and similar dsu graphs greedy implementation shortest paths | Statement | D | Codeforces Round 648 (Div. 2) {1365} | PROGRAMMING | 1500.0 | Editorial — Codeforces Round #648 | 1700 |
| 1877 | Columns Swaps | 2-sat dfs and similar dsu graphs implementation | Statement | G | Codeforces Round 656 (Div. 3) {1385} | PROGRAMMING | Codeforces Round #656 (Div. 3) Editorial | 2300 | |
| 8658 | Peaceful Rooks | dfs and similar dsu graphs | Statement | C | Technocup 2021 - Elimination Round 3 {1411} | PROGRAMMING | 1750.0 | Technocup 2021 Elimination Round 3 and Round #692 (Div. 1 + Div. 2) Editorial | |
| 2818 | Graph and Queries | data structures dfs and similar dsu graphs trees | Statement | D | Codeforces Round 673 (Div. 1) {1416} | PROGRAMMING | 2000.0 | Codeforces Round #673 Editorial | 2600 |
| 619 | Rain of Fire | binary search dfs and similar dsu graphs implementation sortings | Statement | F | Codeforces Round 671 (Div. 2) {1419} | PROGRAMMING | 3000.0 | Codeforces Round #671 Editorial | |
| 1917 | Team-Building | 2-sat dfs and similar dsu graphs | Statement | C | Codeforces Round 680 (Div. 1, based on Moscow Team Olympiad) {1444} | PROGRAMMING | 1500.0 | Codeforces Round #680 Editorial | |
| 6776 | Number of Simple Paths | combinatorics data structures dfs and similar dsu graphs trees | Statement | E | Codeforces Round 686 (Div. 3) {1454} | PROGRAMMING | Codeforces Round #686 (Div. 3) Editorial | ||
| 1772 | Plan of Lectures | dfs and similar dsu graphs | Statement | E | Educational Codeforces Round 100 (Rated for Div. 2) {1463} | PROGRAMMING | Educational Codeforces Round 100 Editorial | ||
| 3079 | Euclid's nightmare | dfs and similar dsu graphs math | Statement | F | Good Bye 2020 {1466} | PROGRAMMING | 1750.0 | Good Bye 2020 Editorial | |
| 4235 | Strange Housing | constructive algorithms dfs and similar dsu graph matchings graphs | Statement | D | Codeforces Round 694 (Div. 1) {1470} | PROGRAMMING | 1500.0 | 86464 | |
| 1770 | Complete the MST | data structures dfs and similar dsu graphs greedy math | Statement | C | Codeforces Round 715 (Div. 1) {1508} | PROGRAMMING | 1500.0 | Codeforces Round #715 Editorial | |
| 2137 | Phoenix and Earthquake | constructive algorithms dfs and similar dsu graphs greedy trees | Statement | F | Codeforces Global Round 14 {1515} | PROGRAMMING | 3250.0 | Editorial | |
| 13976 | Little Alawn's Puzzle | combinatorics dfs and similar dp dsu graphs math | Statement | C | Codeforces LATOKEN Round 1 (Div. 1 + Div. 2) {1534} | PROGRAMMING | 1250.0 | Codeforces LATOKEN Round 1 (Div. 1 + Div. 2) Editorial | |
| 2846 | Figure Fixing | constructive algorithms dfs and similar dsu graphs math | Statement | F | Codeforces Round 726 (Div. 2) {1537} | PROGRAMMING | 2000.0 | Codeforces Round #726 (Div.2) Editorial | |
| 3182 | Mocha and Diana (Hard Version) | brute force constructive algorithms dfs and similar dsu graphs greedy trees two pointers | Statement | D2 | Codeforces Round 738 (Div. 2) {1559} | PROGRAMMING | 1500.0 | Tutorial (en) | 2500 |
| 9746 | The Number of Imposters | constructive algorithms dfs and similar dp dsu graphs | Statement | D | Codeforces Round 747 (Div. 2) {1594} | PROGRAMMING | 1750.0 | 95525 | 1700 |
| 2814 | Cars | constructive algorithms dfs and similar dsu graphs greedy sortings | Statement | E | Codeforces Round 772 (Div. 2) {1635} | PROGRAMMING | 2250.0 | Codeforces Round #772 Editorial | |
| 588 | Air Reform | data structures dfs and similar divide and conquer dsu graphs implementation trees | Statement | E | Codeforces Round 775 (Div. 1, based on Moscow Open Olympiad in Informatics) {1648} | PROGRAMMING | 2500.0 | Codeforces Round #775 Editorial | |
| 2011 | 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 | |
| 11119 | Where is the Pizza? | data structures dfs and similar dsu graphs implementation math | Statement | C | Codeforces Round 788 (Div. 2) {1670} | PROGRAMMING | 1750.0 | Tutorial | 1400 |
| 4133 | Tokitsukaze and Two Colorful Tapes | constructive algorithms dfs and similar dsu graphs greedy | Statement | C | Codeforces Round 789 (Div. 1) {1677} | PROGRAMMING | 1250.0 | Tutorial | |
| 965 | Lenient Vertex Cover | data structures dfs and similar divide and conquer dsu graphs | Statement | F | Educational Codeforces Round 128 (Rated for Div. 2) {1680} | PROGRAMMING | 102852 | ||
| 1404 | ANDfinity | bitmasks brute force constructive algorithms dfs and similar dsu graphs | Statement | E | Codeforces Round 798 (Div. 2) {1689} | PROGRAMMING | 2500.0 | Editorial for Codeforces Round #798 (Div. 2) | |
| 2141 | Number of Groups | data structures dfs and similar dsu graphs greedy sortings | Statement | E | CodeCraft-22 and Codeforces Round 795 (Div. 2) {1691} | PROGRAMMING | 2250.0 | Editorial for CodeCraft-22 and Codeforces Round #795 (Div. 2) | |
| 1164 | Tree Recovery | bitmasks brute force constructive algorithms dfs and similar dsu graphs trees | Statement | F | Codeforces Global Round 21 {1696} | PROGRAMMING | 2500.0 | Editorial of Codeforces Global Round 21 | |
| 1476 | Coloring | brute force combinatorics constructive algorithms dfs and similar dp dsu graphs implementation | Statement | E | Educational Codeforces Round 130 (Rated for Div. 2) {1697} | PROGRAMMING | 103835 | ||
| 18587 | Split Into Two Sets | dfs and similar dsu graph matchings graphs | Statement | E | Codeforces Round 805 (Div. 3) {1702} | PROGRAMMING | 104763 | ||
| 1961 | DFS Trees | data structures dfs and similar dsu graphs greedy trees | Statement | C | Codeforces Round 808 (Div. 1) {1707} | PROGRAMMING | 1250.0 | 104930 | |
| 11031 | Phase Shift | dfs and similar dsu graphs greedy strings | Statement | C | Codeforces Round 824 (Div. 2) {1735} | PROGRAMMING | 1250.0 | Codeforces Round #824 — editorial | |
| 3778 | Permutation Addicts | constructive algorithms dfs and similar dsu graphs trees | Statement | D | Codeforces Global Round 22 {1738} | PROGRAMMING | 2000.0 | Editorial of Codeforces Global Round <strong>22</strong> | |
| 1053 | Tick, Tock | 2-sat combinatorics dfs and similar dsu graphs | Statement | E | Codeforces Round 836 (Div. 2) {1758} | PROGRAMMING | 2250.0 | Codeforces Round #836 (Div. 2) Editorial | |
| 9232 | Lucky Permutation | dfs and similar dsu graphs greedy | Statement | D | Codeforces Round 842 (Div. 2) {1768} | PROGRAMMING | 1750.0 | Codeforces Round #842 (Div. 2) Editorial | |
| 4442 | Koxia and Game | data structures dfs and similar dsu games graph matchings graphs implementation | Statement | D | Good Bye 2022: 2023 is NEAR {1770} | PROGRAMMING | 1500.0 | Good Bye 2022 -- Editorial | |
| 2430 | Edge Reverse | binary search dfs and similar dsu graphs | Statement | E | Codeforces Round 845 (Div. 2) and ByteRace 2023 {1777} | PROGRAMMING | 2250.0 | Codeforces Round #845 (Div. 2) and ByteRace 2023 Editorial | |
| 1209 | XOR, Tree, and Queries | constructive algorithms dfs and similar dsu graphs trees | Statement | F | Codeforces Round 851 (Div. 2) {1788} | PROGRAMMING | 3000.0 | Codeforces Round #851 (Div. 2) Editorial | |
| 1947 | There Should Be a Lot of Maximums | data structures dfs and similar dsu graphs trees | Statement | E | Codeforces Round 862 (Div. 2) {1805} | PROGRAMMING | 2250.0 | Editorial of Codeforces Round #862 (Div. 2) | |
| 3977 | Monsters | brute force data structures dfs and similar dsu graphs implementation trees | Statement | E | CodeTON Round 4 (Div. 1 + Div. 2, Rated, Prizes!) {1810} | PROGRAMMING | 2000.0 | Editorial of CodeTON Round 4 (Div. 1 + Div. 2, Rated, Prizes!) | |
| 2224 | Is It Flower? | dfs and similar dsu graphs implementation | Statement | F | Codeforces Round 863 (Div. 3) {1811} | PROGRAMMING | 114788 | ||
| 27570 | The Lakes | dfs and similar dsu graphs implementation | Statement | E | Codeforces Round 871 (Div. 4) {1829} | PROGRAMMING | Codeforces Round 871 (Div. 4) Editorial | 1100 | |
| 2189 | Great Grids | constructive algorithms dfs and similar dsu graphs math | Statement | E | Codeforces Round 884 (Div. 1 + Div. 2) {1844} | PROGRAMMING | 2000.0 | Codeforces Round #884 (Div. 1 + Div. 2) Editorial | |
| 7646 | Selling a Menagerie | dfs and similar dsu graphs implementation math | Statement | F | Codeforces Round 895 (Div. 3) {1872} | PROGRAMMING | Codeforces Round 895 (Div. 3) Editorial | ||
| 9712 | Mad City | dfs and similar dsu graphs shortest paths | Statement | H | Codeforces Round 898 (Div. 4) {1873} | PROGRAMMING | 120634 | ||
| 1069 | Lexichromatography | combinatorics dfs and similar dsu graphs two pointers | Statement | D | Codeforces Round 902 (Div. 1, based on COMPFEST 15 - Final Round) {1876} | PROGRAMMING | 1750.0 | Codeforces Round #902 (Div. 1, Div. 2, based on COMPFEST 15 — Final Round) Editorial | |
| 2460 | Light Bulbs (Easy Version) | brute force combinatorics dfs and similar dp dsu graphs math | Statement | G1 | Codeforces Round 916 (Div. 3) {1914} | PROGRAMMING | Codeforces Round 916 (Div. 3) Editorial | ||
| 1879 | Light Bulbs (Hard Version) | combinatorics data structures dfs and similar dp dsu graphs hashing | Statement | G2 | Codeforces Round 916 (Div. 3) {1914} | PROGRAMMING | Codeforces Round 916 (Div. 3) Editorial | ||
| 1269 | Smooth Sailing (Easy Version) | binary search data structures dfs and similar dsu graphs | Statement | F1 | Codeforces Round 919 (Div. 2) {1920} | PROGRAMMING | 2500.0 | Editorial for Codeforces Round #919 (Div. 2) | |
| 5505 | Microcycle | data structures dfs and similar dsu graphs greedy trees | Statement | F | Codeforces Round 923 (Div. 3) {1927} | PROGRAMMING | 125597 | ||
| 106 | Parallel Universes | *special constructive algorithms dfs and similar dsu graphs | Statement | A | XVIII Open Olympiad in Informatics - Final Stage, Day 2 (Unrated, Online Mirror, IOI rules) {1940} | PROGRAMMING | |||
| 44 | Burenka and Pether | *special data structures dfs and similar divide and conquer dsu graphs sortings trees | Statement | C | XVIII Open Olympiad in Informatics - Final Stage, Day 2 (Unrated, Online Mirror, IOI rules) {1940} | PROGRAMMING | |||
| 7396 | Maximize the Largest Component (Easy Version) | brute force data structures dfs and similar dsu graphs implementation | Statement | H1 | Codeforces Round 952 (Div. 4) {1985} | PROGRAMMING | Codeforces Round 952 (Div. 4) Editorial | ||
| 6691 | Non-academic Problem | combinatorics dfs and similar dsu graphs | Statement | F | Codeforces Round 954 (Div. 3) {1986} | PROGRAMMING | 130762 | ||
| 7559 | Connect the Dots | brute force dfs and similar dp dsu graphs math trees | Statement | D | Codeforces Round 976 (Div. 2) and Divide By Zero 9.0 {2020} | PROGRAMMING | 1500.0 | Tutorial for Codeforces Round 976 (Div. 2) and Divide By Zero 9.0 | |
| 778 | Billetes MX (Easy Version) | 2-sat binary search combinatorics dfs and similar dsu graphs | Statement | E1 | Codeforces Round 978 (Div. 2) {2022} | PROGRAMMING | 2250.0 | Codeforces Round 978 (Div 2) Editorial | |
| 728 | Billetes MX (Hard Version) | binary search combinatorics dfs and similar dsu graphs | Statement | E2 | Codeforces Round 978 (Div. 2) {2022} | PROGRAMMING | 1000.0 | Codeforces Round 978 (Div 2) Editorial | |
| 4000 | Cool Graph | constructive algorithms data structures dfs and similar dsu graphs trees | Statement | D | Refact.ai Match 1 (Codeforces Round 985) {2029} | PROGRAMMING | 2250.0 | Refact.ai Match 1 (Codeforces Round 985) Editorial | |
| 3965 | Medium Demon Problem (hard version) | dfs and similar dp dsu graphs implementation trees | Statement | G2 | Codeforces Round 993 (Div. 4) {2044} | PROGRAMMING | Codeforces Round 993 (Div. 4) Editorial | ||
| 12629 | Graph Composition | dfs and similar dsu graphs greedy | Statement | E | Codeforces Round 998 (Div. 3) {2060} | PROGRAMMING | Codeforces Round 998 (Div. 3) Editorial | ||
| 380 | Porto Vs. Benfica | data structures dfs and similar dsu graphs shortest paths | Statement | E | European Championship 2025 - Online Mirror (Unrated, ICPC Rules, Teams Preferred) {2068} | PROGRAMMING | 140239 | ||
| 16451 | Disappearing Permutation | dfs and similar dsu graphs greedy implementation | Statement | C | Educational Codeforces Round 177 (Rated for Div. 2) {2086} | PROGRAMMING | Educational Codeforces Round 177 Editorial | ||
| 2562 | Red Light, Green Light (Hard version) | binary search dfs and similar dp dsu graphs implementation number theory | Statement | D2 | Codeforces Round 1030 (Div. 2) {2118} | PROGRAMMING | 1000.0 | Codeforces Round 1030 (Div. 2) Editorial | |
| 4887 | 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 | |
| 85 | Merging Vertices in a Graph | *special dfs and similar dsu graphs | Statement | H | Kotlin Heroes: Episode 13 {2141} | PROGRAMMING | Kotlin Heroes 13 Editorial | ||
| 743 | Juan's Colorful Tree | data structures data structures dfs and similar dfs and similar dsu graphs graphs trees | Statement | F | Codeforces Round 1056 (Div. 2) {2155} | PROGRAMMING | 3000.0 | Codeforces Round 1056 (Div. 2) Editorial | |
| 3098 | Journey | dfs and similar dsu graphs greedy | Statement | E | Codeforces Global Round 30 (Div. 1 + Div. 2) {2164} | PROGRAMMING | 2250.0 | Codeforces Global Round 30 Editorial | |
| 4705 | Tree Orientation (Easy Version) | constructive algorithms dfs and similar dsu graphs greedy trees | Statement | D1 | Codeforces Round 1086 (Div. 2) {2208} | PROGRAMMING | 1250.0 | Tutorial | |
| 2050 | Tree Orientation (Hard Version) | data structures dfs and similar dsu graphs greedy matrices sortings trees | Statement | D2 | Codeforces Round 1086 (Div. 2) {2208} | PROGRAMMING | 1250.0 | Tutorial |