Review the problem statement from Codeforces (link will open a new tab). When you've matched your problem, go to the solutions.
Search on plain tags, ratings, names, and problem text. Example: brute force or binary search
Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 2310 | Cactus | data structures dfs and similar dp graphs trees | Statement | E | Codeforces Round 143 (Div. 2) {231} | PROGRAMMING | Tutorial Codeforces Round #143 | 2400 | |
| 1850 | Little Girl and Problem on Trees | data structures graphs trees | Statement | E | Codeforces Round 169 (Div. 2) {276} | PROGRAMMING | Codeforces Round #169 — Unofficial Editorial | 2300 | |
| 6811 | Water Tree | data structures dfs and similar graphs trees | Statement | D | Codeforces Round 200 (Div. 1) {343} | PROGRAMMING | Codeforces Round #200 Tutorial | 2100 | |
| 1796 | On Changing Tree | data structures graphs trees | Statement | C | Codeforces Round 232 (Div. 1) {396} | PROGRAMMING | 1500.0 | Codeforces Round #232 Editorial (restored) | |
| 545 | Big Problems for Organizers | data structures graphs trees | Statement | D | RCC 2014 Warmup (Div. 1) {418} | PROGRAMMING | RCC 2014 WarmUp Analysis | 2700 | |
| 2822 | Tourists | data structures dfs and similar graphs trees | Statement | E | Codeforces Round 278 (Div. 1) {487} | PROGRAMMING | Tutorial | 3100 | |
| 1211 | Ann and Half-Palindrome | data structures dp graphs string suffix structures strings trees | Statement | E | Codeforces Round 311 (Div. 2) {557} | PROGRAMMING | Codeforces Round #311 (Div.2) Editorial | 2700 | |
| 1421 | Happy Tree Party | data structures dfs and similar graphs math trees | Statement | D | Codeforces Round 329 (Div. 2) {593} | PROGRAMMING | 2300 | ||
| 10186 | Minimum spanning tree for each edge | data structures dfs and similar dsu graphs trees | Statement | E | Educational Codeforces Round 3 {609} | PROGRAMMING | Editorial | 2100 | |
| 450 | Bear and Chemistry | data structures dfs and similar graphs trees | Statement | F | VK Cup 2016 - Round 1 {639} | PROGRAMMING | Tutorial | 3300 | |
| 4334 | Centroids | data structures dfs and similar dp graphs greedy trees | Statement | C | AIM Tech Round 3 (Div. 1) {708} | PROGRAMMING | Editorial | 2500 | |
| 1295 | Drivers Dissatisfaction | data structures dsu graphs trees | Statement | F | Codeforces Round 378 (Div. 2) {733} | PROGRAMMING | Codeforces Round #378 (Div. 2) editorial | 2500 | |
| 5098 | Alyona and a tree | binary search data structures dfs and similar graphs trees | Statement | B | Codeforces Round 381 (Div. 1) {739} | PROGRAMMING | 48582 | 2000 | |
| 646 | Can Bash Save the Day? | data structures divide and conquer graphs trees | Statement | G | Codecraft-17 and Codeforces Round 391 (Div. 1 + Div. 2, combined) {757} | PROGRAMMING | CodeCraft-17 and Codeforces Round #391 (Div. 1 + Div. 2, combined) Editorial | 2500 | |
| 644 | Timofey and a flat tree | data structures graphs hashing shortest paths trees | Statement | D | Codeforces Round 395 (Div. 1) {763} | PROGRAMMING | Codeforces Round #395 [Editorial] | 2800 | |
| 511 | Sherlock's bet to Moriarty | constructive algorithms data structures divide and conquer geometry graphs implementation trees | Statement | F | 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 | 2700 | |
| 750 | ALT | data structures flows graphs trees | Statement | E | Codeforces Round 406 (Div. 1) {786} | PROGRAMMING | Codeforces Round #406 Editorial | 3200 | |
| 1368 | Best Edge Weight | data structures dfs and similar graphs trees | Statement | D | Codeforces Round 423 (Div. 1, rated, based on VK Cup Finals) {827} | PROGRAMMING | Codeforces Round #423 Analysis | 2700 | |
| 3035 | Imbalance Value of a Tree | data structures dsu graphs trees | Statement | F | Educational Codeforces Round 36 (Rated for Div. 2) {915} | PROGRAMMING | 57123 | 2500 | |
| 744 | Maximum Control (medium) | data structures dfs and similar graphs greedy trees | Statement | B2 | Helvetic Coding Contest 2018 online mirror (teams allowed, unrated) {958} | PROGRAMMING | helvetic-coding-contest-2018-editorial.pdf | 2400 | |
| 1466 | Leaf Sets | data structures dfs and similar dsu graphs greedy sortings trees | Statement | F | Codeforces Round 510 (Div. 2) {1042} | PROGRAMMING | Tutorial | 2400 | |
| 1091 | Tree | data structures dfs and similar dp graphs trees | Statement | E | CodeCraft-19 and Codeforces Round 537 (Div. 2) {1111} | PROGRAMMING | CodeCraft-19 and Codeforces Round #537 (Div. 2) Editorial | 2800 | |
| 664 | Daleks' Invasion (hard) | data structures dsu graphs trees | Statement | E3 | Helvetic Coding Contest 2019 online mirror (teams allowed, unrated) {1184} | PROGRAMMING | helvetic-coding-contest-2019-editorial.pdf | 2500 | |
| 1362 | Koala and Notebook | data structures dfs and similar graphs shortest paths strings trees | Statement | F | Codeforces Round 584 - Dasha Code Championship - Elimination Round (rated, open for everyone, Div. 1 + Div. 2) {1209} | PROGRAMMING | 69791 | 2600 | |
| 716 | Forced Online Queries Problem | data structures divide and conquer dsu graphs trees | Statement | F | Educational Codeforces Round 72 (Rated for Div. 2) {1217} | PROGRAMMING | Educational Codeforces Round 72 Editorial | 2800 | |
| 949 | Economic Difficulties | data structures dfs and similar dp flows graphs trees | Statement | F | Codeforces Round 603 (Div. 2) {1263} | PROGRAMMING | Разбор Codeforces Round #603 (Div. 2) | 2500 | |
| 4320 | Segment Tree | data structures dsu graphs trees | Statement | D | Educational Codeforces Round 78 (Rated for Div. 2) {1278} | PROGRAMMING | Educational Codeforces Round 78 Editorial | 2100 | |
| 412 | New Year and Social Network | data structures graph matchings graphs math trees | Statement | F | Hello 2020 {1284} | PROGRAMMING | Hello 2020 Editorial | 3100 | |
| 2000 | Delete a Segment | brute force constructive algorithms data structures dp graphs sortings trees two pointers | Statement | E | Codeforces Round 613 (Div. 2) {1285} | PROGRAMMING | Codeforces Round #613 (Div. 2) Editorial | 2300 | |
| 5454 | Numbers on Tree | constructive algorithms data structures dfs and similar graphs greedy trees | Statement | B | Codeforces Round 612 (Div. 1) {1286} | PROGRAMMING | Codeforces Round #612 - Editorial | 2000 | |
| 278 | Journey | data structures divide and conquer graphs trees | Statement | F | Codeforces Round 635 (Div. 1) {1336} | PROGRAMMING | 3250.0 | Codeforces Round #635 Editorial | 3600 |
| 4951 | Ehab's Last Corollary | constructive algorithms data structures dfs and similar dp graphs implementation trees | Statement | D | Codeforces Round 649 (Div. 2) {1364} | PROGRAMMING | 2000.0 | Codeforces round #649 editorial | 2100 |
| 675 | Shifting Dominoes | data structures geometry graphs trees | Statement | G | Codeforces Global Round 8 {1368} | PROGRAMMING | 3500.0 | Codeforces Global Round 8: editorial | |
| 6902 | Captain Flint and Treasure | data structures dfs and similar dp graphs greedy implementation trees | Statement | D | Codeforces Round 660 (Div. 2) {1388} | PROGRAMMING | 2000.0 | Codeforces Round #660 Editorial | 2000 |
| 393 | Spring cleaning | *special data structures dfs and similar graphs trees | Statement | B | Central-European Olympiad in Informatics, CEOI 2020, Day 2 (IOI, Unofficial Mirror Contest, Unrated) {1403} | PROGRAMMING | CEOI 2020 Online Mirror — Day 2 Tutorial | ||
| 2693 | 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 |
| 6596 | 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 | ||
| 420 | Squares | constructive algorithms data structures graphs trees | Statement | F | Codeforces Round 706 (Div. 1) {1495} | PROGRAMMING | 3250.0 | Codeforces Round #706 Editorial | |
| 2289 | Nastia Plays with a Tree | constructive algorithms data structures dfs and similar dp flows graphs greedy implementation trees | Statement | D | Codeforces Round 720 (Div. 2) {1521} | PROGRAMMING | 2250.0 | 90477 | |
| 895 | Jumping Around | data structures divide and conquer dp dsu graphs shortest paths trees | Statement | F | Educational Codeforces Round 111 (Rated for Div. 2) {1550} | PROGRAMMING | Educational Codeforces Round 111 Editorial | ||
| 1043 | Good Graph | data structures dsu graphs trees | Statement | F | Educational Codeforces Round 112 (Rated for Div. 2) {1555} | PROGRAMMING | 93389 | 2700 | |
| 1148 | Cats on the Upgrade (easy version) | data structures dfs and similar divide and conquer dp graphs trees | Statement | E1 | Codeforces Round 765 (Div. 2) {1625} | PROGRAMMING | 2000.0 | Editorial of Codeforces Round #765 (Div. 2) | |
| 659 | Cats on the Upgrade (hard version) | data structures dfs and similar graphs trees | Statement | E2 | Codeforces Round 765 (Div. 2) {1625} | PROGRAMMING | 1250.0 | Editorial of Codeforces Round #765 (Div. 2) | |
| 504 | 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 | |
| 454 | Snowy Mountain | data structures graphs greedy shortest paths trees | Statement | G | Codeforces Round 778 (Div. 1 + Div. 2, based on Technocup 2022 Final Round) {1654} | PROGRAMMING | 3500.0 | Editorial of Codeforces Round #778 (Div. 1 + Div. 2, based on Technocup 2022 Final Round) | 2900 |
| 1893 | DFS Trees | data structures dfs and similar dsu graphs greedy trees | Statement | C | Codeforces Round 808 (Div. 1) {1707} | PROGRAMMING | 1250.0 | 104930 | |
| 6216 | Reset K Edges | binary search data structures dfs and similar graphs greedy trees | Statement | D | Educational Codeforces Round 136 (Rated for Div. 2) {1739} | PROGRAMMING | Educational Codeforces Round 136 Editorial | ||
| 10240 | SlavicG's Favorite Problem | bitmasks brute force constructive algorithms data structures dfs and similar graphs greedy | Statement | G | Codeforces Round 835 (Div. 4) {1760} | PROGRAMMING | 109348 | ||
| 1902 | 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) | |
| 3896 | 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!) | |
| 4018 | Vlad and the Mountains | data structures dsu graphs implementation sortings trees two pointers | Statement | G | Codeforces Round 888 (Div. 3) {1851} | PROGRAMMING | 118667 | ||
| 519 | Teleportation in Byteland | data structures divide and conquer graphs shortest paths trees | Statement | F | Codeforces Round 892 (Div. 2) {1859} | PROGRAMMING | 3000.0 | Video solutions from Geothermal. | |
| 121 | Standard Graph Problem | data structures graphs greedy trees | Statement | H | CodeTON Round 6 (Div. 1 + Div. 2, Rated, Prizes!) {1870} | PROGRAMMING | 4000.0 | CodeTON Round 6 (Div. 1 + Div. 2, Rated, Prizes!) Editorial | |
| 495 | Beautiful Tree | data structures dfs and similar graphs trees | Statement | F | Codeforces Round 914 (Div. 2) {1904} | PROGRAMMING | 3500.0 | Codeforces Round 914 (Div. 2) Editorial | |
| 641 | Smooth Sailing (Hard Version) | binary search data structures dsu graphs trees | Statement | F2 | Codeforces Round 919 (Div. 2) {1920} | PROGRAMMING | 2500.0 | Editorial for Codeforces Round #919 (Div. 2) | |
| 5360 | Microcycle | data structures dfs and similar dsu graphs greedy trees | Statement | F | Codeforces Round 923 (Div. 3) {1927} | PROGRAMMING | 125597 | ||
| 43 | 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 | |||
| 1689 | Yasya and the Mysterious Tree | bitmasks data structures dfs and similar graphs strings trees | Statement | G | Codeforces Round 950 (Div. 3) {1980} | PROGRAMMING | 130135 | ||
| 1214 | Turtle and Intersected Segments | data structures dsu graphs greedy | Statement | E | Codeforces Round 949 (Div. 2) {1981} | PROGRAMMING | 2500.0 | Simplified Chinese Tutorial | |
| 1918 | Digital Village (Easy Version) | brute force data structures dp dsu graphs greedy implementation math shortest paths trees | Statement | E1 | Codeforces Round 977 (Div. 2, based on COMPFEST 16 - Final Round) {2021} | PROGRAMMING | 1750.0 | Codeforces Round #977 (Div. 2, based on COMPFEST 16 — Final Round) Editorial | |
| 1198 | Digital Village (Hard Version) | data structures dp dsu graphs math trees | Statement | E2 | Codeforces Round 977 (Div. 2, based on COMPFEST 16 - Final Round) {2021} | PROGRAMMING | 750.0 | Codeforces Round #977 (Div. 2, based on COMPFEST 16 — Final Round) Editorial | |
| 3906 | 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 | |
| 6175 | Genokraken | binary search constructive algorithms data structures graphs interactive trees two pointers | Statement | D | Codeforces Round 983 (Div. 2) {2032} | PROGRAMMING | 1750.0 | Codeforces Round 983 (Div. 2) Editorial | |
| 444 | The Game (Hard Version) | data structures dfs and similar games graphs trees | Statement | E2 | Ethflow Round 1 (Codeforces Round 1001, Div. 1 + Div. 2) {2062} | PROGRAMMING | 2500.0 | Ethflow Round 1 (Codeforces Round 1001, Div. 1 + Div. 2) Editorial | |
| 14529 | Remove Exactly Two | brute force data structures dp graphs greedy sortings trees | Statement | C | Codeforces Round 1000 (Div. 2) {2063} | PROGRAMMING | 1500.0 | Codeforces Round 1000 (Div. 2) — Editorial | |
| 7049 | Skibidus and Slay | data structures dfs and similar graphs greedy trees | Statement | F | Codeforces Round 1003 (Div. 4) {2065} | PROGRAMMING | Video Tutorial | ||
| 4272 | 1-1-1, Free Tree! | data structures dfs and similar graphs trees | Statement | F | Codeforces Round 1037 (Div. 3) {2126} | PROGRAMMING | 144845 | ||
| 565 | 23 Rises Again | brute force data structures dfs and similar dp flows graphs implementation probabilities trees | Statement | H | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) {2127} | PROGRAMMING | 4000.0 | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) Editorial | |
| 625 | 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 | |
| 1332 | Jerry and Tom | data structures dfs and similar games graphs greedy trees | Statement | C | Codeforces Round 1077 (Div. 1) {2187} | PROGRAMMING | 1750.0 | Codeforces Round 1077 (Div. 1, Div. 2) Editorial | |
| 1014 | Idiot First Search and Queries | binary search data structures graphs trees | Statement | G | Codeforces Round 1080 (Div. 3) {2195} | PROGRAMMING | Codeforces Round 1080 (Div. 3) Editorial | ||
| 1745 | 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 |