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< 1 2 3 4 5 >Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 986 | Peterson Polyglot | brute force dfs and similar dsu hashing strings trees | Statement | C | Codeforces Round 402 (Div. 1) {778} | PROGRAMMING | Codeforces Round #402, Editorial | 2600 | |
| 10045 | Andryusha and Colored Balloons | dfs and similar graphs greedy trees | Statement | C | Технокубок 2017 - Финал (только для онсайт-финалистов) {780} | PROGRAMMING | Technocup 2017 Finals and Codeforces Round #403 Editorial | 1500 | |
| 753 | ALT | data structures flows graphs trees | Statement | E | Codeforces Round 406 (Div. 1) {786} | PROGRAMMING | Codeforces Round #406 Editorial | 3200 | |
| 168 | Rap God | data structures dfs and similar hashing strings trees | Statement | D | Codeforces Round 406 (Div. 1) {786} | PROGRAMMING | Codeforces Round #406 Editorial | 3300 | |
| 3412 | Paths in a Complete Binary Tree | bitmasks trees | Statement | D | Educational Codeforces Round 18 {792} | PROGRAMMING | Educational Codeforces Round 18 - Editorial | 1800 | |
| 305 | Problem of offices | constructive algorithms dfs and similar dp trees | Statement | E | Tinkoff Challenge - Elimination Round {793} | PROGRAMMING | 51685 | 2800 | |
| 3236 | Bank Hacking | constructive algorithms data structures dp trees | Statement | C | Codeforces Round 408 (Div. 2) {796} | PROGRAMMING | Tutorial | 1900 | |
| 7278 | Police Stations | constructive algorithms dfs and similar dp graphs shortest paths trees | Statement | D | Codeforces Round 408 (Div. 2) {796} | PROGRAMMING | Tutorial | 2100 | |
| 6584 | Send the Fool Further! (easy) | dfs and similar graphs trees | Statement | J1 | Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} | PROGRAMMING | helvetic-coding-contest-2017-editorial.pdf | 1400 | |
| 6421 | Send the Fool Further! (easy) | dfs and similar graphs trees | Statement | J | Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} | PROGRAMMING | helvetic-coding-contest-2017-editorial.pdf | 1500 | |
| 736 | Send the Fool Further! (medium) | dp trees | Statement | J2 | Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} | PROGRAMMING | helvetic-coding-contest-2017-editorial.pdf | 2100 | |
| 726 | Send the Fool Further! (medium) | dp trees | Statement | K | Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} | PROGRAMMING | helvetic-coding-contest-2017-editorial.pdf | 2100 | |
| 388 | Send the Fool Further! (hard) | dfs and similar dp math trees | Statement | J3 | Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} | PROGRAMMING | helvetic-coding-contest-2017-editorial.pdf | 2400 | |
| 364 | Send the Fool Further! (hard) | dfs and similar dp math trees | Statement | L | Helvetic Coding Contest 2017 online mirror (teams allowed, unrated) {802} | PROGRAMMING | helvetic-coding-contest-2017-editorial.pdf | 2800 | |
| 1561 | Expected diameter of a tree | binary search brute force dfs and similar dp sortings trees | Statement | D | Codeforces Round 411 (Div. 1) {804} | PROGRAMMING | Codeforces Round #411 Editorial | 2600 | |
| 855 | Surprise me! | divide and conquer math number theory trees | Statement | E | Codeforces Round 415 (Div. 1) {809} | PROGRAMMING | 52099 | 3000 | |
| 1345 | Sagheer and Apple Tree | games trees | Statement | E | Codeforces Round 417 (Div. 2) {812} | PROGRAMMING | [Editorial] Codeforces Round #417 (Div. 2) | 2200 | |
| 350 | Sagheer and Kindergarten | dfs and similar graphs implementation trees | Statement | D | Codeforces Round 417 (Div. 2) {812} | PROGRAMMING | [Editorial] Codeforces Round #417 (Div. 2) | 2700 | |
| 2588 | An overnight dance in discotheque | dfs and similar dp geometry greedy trees | Statement | D | Codeforces Round 418 (Div. 2) {814} | PROGRAMMING | Codeforces Round #418 (Div. 2) Editorial | 2000 | |
| 3347 | Karen and Supermarket | brute force dp trees | Statement | C | Codeforces Round 419 (Div. 1) {815} | PROGRAMMING | Codeforces Round #419 Editorial | 2500 | |
| 3753 | Choosing The Commander | bitmasks data structures trees | Statement | E | Educational Codeforces Round 23 {817} | PROGRAMMING | 52638 | 2100 | |
| 3393 | MEX Queries | binary search data structures trees | Statement | F | Educational Codeforces Round 23 {817} | PROGRAMMING | 52638 | 2400 | |
| 6076 | Okabe and Banana Trees | brute force math | Statement | B | Codeforces Round 420 (Div. 2) {821} | PROGRAMMING | Tutorial | 1300 | |
| 7963 | Okabe and Boxes | data structures greedy trees | Statement | C | Codeforces Round 420 (Div. 2) {821} | PROGRAMMING | Tutorial | 1600 | |
| 375 | Madness | constructive algorithms dfs and similar trees | Statement | F | Codeforces Round 422 (Div. 2) {822} | PROGRAMMING | Codeforces Round #422 (Div. 2) Editorial | 2700 | |
| 1483 | Tree Queries | dfs and similar graphs trees | Statement | G | Educational Codeforces Round 25 {825} | PROGRAMMING | Educational Codeforces Round 25 - Editorial | 2600 | |
| 3702 | High Load | constructive algorithms greedy implementation trees | Statement | B | Codeforces Round 423 (Div. 1, rated, based on VK Cup Finals) {827} | PROGRAMMING | Codeforces Round #423 Analysis | 1800 | |
| 1384 | 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 | |
| 982 | Singer House | combinatorics dp graphs trees | Statement | D | Codeforces Round 424 (Div. 1, rated, based on VK Cup Finals) {830} | PROGRAMMING | Codeforces Round #424 Editorial | 2800 | |
| 338 | Perpetual Motion Machine | constructive algorithms dp graphs implementation math trees | Statement | E | Codeforces Round 424 (Div. 1, rated, based on VK Cup Finals) {830} | PROGRAMMING | Codeforces Round #424 Editorial | 3100 | |
| 4542 | Misha, Grisha and Underground | dfs and similar graphs trees | Statement | D | Codeforces Round 425 (Div. 2) {832} | PROGRAMMING | Codeforces Round #425 (Div.2) Editorial | 1900 | |
| 487 | Red-Black Cobweb | data structures divide and conquer implementation trees | Statement | D | Codeforces Round 426 (Div. 1) {833} | PROGRAMMING | Codeforces Round #426 Editorial | 2800 | |
| 1254 | Roads in the Kingdom | dfs and similar dp graphs trees | Statement | F | Codeforces Round 427 (Div. 2) {835} | PROGRAMMING | Editorial | 2400 | |
| 1098 | Diverging Directions | data structures dfs and similar trees | Statement | B | IndiaHacks 2nd Elimination 2017 (unofficial, unrated mirror, ICPC rules) {838} | PROGRAMMING | 53736 | 2100 | |
| 20338 | Journey | dfs and similar dp graphs probabilities trees | Statement | C | Codeforces Round 428 (Div. 2) {839} | PROGRAMMING | Codeforces Round #428 editorial | 1500 | |
| 578 | In a Trap | trees | Statement | E | Codeforces Round 429 (Div. 1) {840} | PROGRAMMING | Editorial | 3200 | |
| 3777 | Ilya And The Tree | dfs and similar graphs math number theory trees | Statement | C | Codeforces Round 430 (Div. 2) {842} | PROGRAMMING | Tutorial Codeforces Round #430 (Div. 2) | 2000 | |
| 502 | Nikita and game | binary search dfs and similar divide and conquer graphs trees | Statement | E | Codeforces Round 430 (Div. 2) {842} | PROGRAMMING | Tutorial Codeforces Round #430 (Div. 2) | 3000 | |
| 408 | Upgrading Tree | constructive algorithms dfs and similar graphs math trees | Statement | C | AIM Tech Round 4 (Div. 1) {843} | PROGRAMMING | AIM Tech Round 4 -- Editorial | 2900 | |
| 1035 | Chemistry in Berland | dfs and similar greedy trees | Statement | E | Educational Codeforces Round 28 {846} | PROGRAMMING | 54357 | 2400 | |
| 349 | Berland SU Computer Network | dfs and similar hashing trees | Statement | L | 2017-2018 ACM-ICPC, NEERC, Southern Subregional Contest, qualification stage (Online Mirror, ACM-ICPC Rules, Teams Preferred) {847} | PROGRAMMING | 2500 | ||
| 749 | Dating | brute force dfs and similar graphs trees | Statement | I | Bubble Cup X - Finals [Online Mirror] {852} | PROGRAMMING | Tutorial | 2500 | |
| 2418 | Helga Hufflepuff's Cup | dp trees | Statement | C | Manthan, Codefest 17 {855} | PROGRAMMING | 54750 | 2000 | |
| 584 | Rowena Ravenclaw's Diadem | trees | Statement | D | Manthan, Codefest 17 {855} | PROGRAMMING | 54750 | 2400 | |
| 284 | Harry Vs Voldemort | dfs and similar dp graphs trees | Statement | G | Manthan, Codefest 17 {855} | PROGRAMMING | 54750 | 3000 | |
| 2120 | Desk Disorder | combinatorics dfs and similar dsu graphs trees | Statement | E | MemSQL Start[c]UP 3.0 - Round 1 {859} | PROGRAMMING | Tutorial | 2100 | |
| 1133 | Third Month Insanity | dp probabilities trees | Statement | D | MemSQL Start[c]UP 3.0 - Round 1 {859} | PROGRAMMING | Tutorial | 2100 | |
| 513 | Arkady and a Nobody-men | data structures dfs and similar trees | Statement | E | Codeforces Round 434 (Div. 1, based on Technocup 2018 Elimination Round 1) {860} | PROGRAMMING | Codeforces Round 434 Div.1+Div.2 (and Technocup 2018 — Elimination Round 1) Editorial | 2600 | |
| 26108 | Mahmoud and Ehab and the bipartiteness | dfs and similar graphs trees | Statement | B | Codeforces Round 435 (Div. 2) {862} | PROGRAMMING | Codeforces round #435 editorial | 1400 | |
| 675 | Cities Excursions | dfs and similar graphs trees | Statement | F | Codeforces Round 436 (Div. 2) {864} | PROGRAMMING | Codeforces Round #436 (Div.2) Разбор | 2700 | |
| 565 | Policeman and a Tree | dp graphs trees | Statement | E | Codeforces Round 438 by Sberbank and Barcelona Bootcamp (Div. 1 + Div. 2 combined) {868} | PROGRAMMING | 55046 | 2600 | |
| 1318 | 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 | |
| 177 | Restore the Tree | graphs greedy trees | Statement | E | Codeforces Round 440 (Div. 1, based on Technocup 2018 Elimination Round 2) {871} | PROGRAMMING | Editorial Codeforces Round 440 Div.1+Div.2 (and Technocup 2018 — Elimination Round 2) | 2800 | |
| 5554 | Danil and a Part-time Job | bitmasks data structures trees | Statement | E | Codeforces Round 442 (Div. 2) {877} | PROGRAMMING | 55362 | 2000 | |
| 1217 | Road Widening | constructive algorithms greedy implementation | Statement | K | 2017-2018 ACM-ICPC, NEERC, Southern Subregional Contest (Online Mirror, ACM-ICPC Rules, Teams Preferred) {883} | PROGRAMMING | 2100 | ||
| 5682 | Petya and Catacombs | dsu greedy implementation trees | Statement | C | Технокубок 2018 - Отборочный Раунд 3 {886} | PROGRAMMING | Editorial Codeforces Round 445 (and Technocup 2018 — Elimination Round 3) | 1300 | |
| 236 | Sloth | dfs and similar dp graph matchings trees | Statement | D | Codeforces Round 446 (Div. 1) {891} | PROGRAMMING | Codeforces Round #446 Editorial | 3000 | |
| 2511 | Subtree Minimum Query | data structures trees | Statement | F | Educational Codeforces Round 33 (Rated for Div. 2) {893} | PROGRAMMING | 55989 | 2300 | |
| 1206 | Ralph And His Tour in Binary Country | brute force data structures trees | Statement | D | Codeforces Round 447 (Div. 2) {894} | PROGRAMMING | Codeforces Round #447 (Div.2 Only) Editorial | 2300 | |
| 3135 | Ralph and Mushrooms | dp graphs | Statement | E | Codeforces Round 447 (Div. 2) {894} | PROGRAMMING | Codeforces Round #447 (Div.2 Only) Editorial | 2400 | |
| 5391 | Hashing Trees | constructive algorithms trees | Statement | A | Codeforces Round 453 (Div. 1) {901} | PROGRAMMING | Codeforces Round #453 (Div. 1 & Div. 2) Editorial | 1500 | |
| 2300 | Tree Destruction | constructive algorithms dfs and similar graphs greedy trees | Statement | F | Educational Codeforces Round 35 (Rated for Div. 2) {911} | PROGRAMMING | T | 2500 | |
| 19603 | Christmas Spruce | implementation trees | Statement | B | Hello 2018 {913} | PROGRAMMING | Tutorial | 1200 | |
| 1944 | Palindromes in a Tree | bitmasks data structures divide and conquer trees | Statement | E | Codecraft-18 and Codeforces Round 458 (Div. 1 + Div. 2, combined) {914} | PROGRAMMING | Tutorial | 2400 | |
| 279 | Ember and Storm's Tree Game | combinatorics dp games trees | Statement | H | Codecraft-18 and Codeforces Round 458 (Div. 1 + Div. 2, combined) {914} | PROGRAMMING | Tutorial | 2900 | |
| 3091 | Imbalance Value of a Tree | data structures dsu graphs trees | Statement | F | Educational Codeforces Round 36 (Rated for Div. 2) {915} | PROGRAMMING | 57123 | 2500 | |
| 567 | Jamie and To-do List | data structures interactive trees | Statement | D | Codeforces Round 457 (Div. 2) {916} | PROGRAMMING | Codeforces Round #457 (Div. 2) Editorial | 2600 | |
| 2124 | Jamie and Tree | data structures trees | Statement | E | Codeforces Round 457 (Div. 2) {916} | PROGRAMMING | Codeforces Round #457 (Div. 2) Editorial | 2600 | |
| 1477 | Stranger Trees | dp math matrices trees | Statement | D | Codeforces Round 459 (Div. 1) {917} | PROGRAMMING | Codeforces Round #459 Editorial | 2600 | |
| 186 | Upside Down | data structures string suffix structures strings trees | Statement | E | Codeforces Round 459 (Div. 1) {917} | PROGRAMMING | Codeforces Round #459 Editorial | 3000 | |
| 2476 | Birds | dp | Statement | E | Codeforces Round 461 (Div. 2) {922} | PROGRAMMING | 57605 | 2300 | |
| 4733 | Perfect Security | data structures greedy strings trees | Statement | C | VK Cup 2018 - Round 1 {923} | PROGRAMMING | VK Cup 2018 Round 1 and CF Round #470 (div. 1 & 2) editorial | 1900 | |
| 139 | Public Service | constructive algorithms graphs trees | Statement | F | VK Cup 2018 - Round 1 {923} | PROGRAMMING | VK Cup 2018 Round 1 and CF Round #470 (div. 1 & 2) editorial | 2900 | |
| 542 | May Holidays | data structures trees | Statement | E | VK Cup 2018 - Round 3 {925} | PROGRAMMING | Разбор VK 2018 Round 3 + Codeforces Round #477 | 2900 | |
| 833 | Autocompletion | *special strings trees | Statement | D | VK Cup 2018 - Квалификация 1 {928} | PROGRAMMING | 2400 | ||
| 8438 | Peculiar apple-tree | dfs and similar graphs trees | Statement | A | Codeforces Round 468 (Div. 1, based on Technocup 2018 Final Round) {930} | PROGRAMMING | Codeforces Round #468 and Technocup 2018 Final Round Analysis | 1500 | |
| 1992 | Tree | binary search dp trees | Statement | D | ICM Technex 2018 and Codeforces Round 463 (Div. 1 + Div. 2, combined) {932} | PROGRAMMING | 57796 | 2200 | |
| 981 | Fafa and Ancient Mathematics | dfs and similar dp trees | Statement | E | Codeforces Round 465 (Div. 2) {935} | PROGRAMMING | editorial | 2500 | |
| 254 | Iqea | data structures dfs and similar divide and conquer dsu shortest paths trees | Statement | E | Codeforces Round 467 (Div. 1) {936} | PROGRAMMING | Codeforces Round #467, Editorial | 3300 | |
| 1966 | Heaps | dp trees | Statement | F | Codeforces Round 471 (Div. 2) {955} | PROGRAMMING | Editorial | 2800 | |
| 748 | 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 | |
| 6214 | Mahmoud and Ehab and the wrong algorithm | constructive algorithms trees | Statement | C | Codeforces Round 473 (Div. 2) {959} | PROGRAMMING | Codeforces round #473 editorial | 1500 | |
| 1948 | Full Binary Tree Queries | brute force implementation trees | Statement | D | 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 | 2100 | |
| 2290 | Alternating Tree | combinatorics dfs and similar divide and conquer dp probabilities trees | Statement | E | 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 | 2200 | |
| 349 | Santa's Gift | data structures trees | Statement | H | 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 | 3000 | |
| 1597 | Simple Cycles Edges | dfs and similar graphs trees | Statement | F | Educational Codeforces Round 42 (Rated for Div. 2) {962} | PROGRAMMING | Educational Codeforces Round 42 Editorial | 2400 | |
| 207 | Visible Black Areas | data structures dsu geometry trees | Statement | G | Educational Codeforces Round 42 (Rated for Div. 2) {962} | PROGRAMMING | Educational Codeforces Round 42 Editorial | 2900 | |
| 3008 | Destruction of a Tree | constructive algorithms dfs and similar dp greedy trees | Statement | B | Tinkoff Internship Warmup Round 2018 and Codeforces Round 475 (Div. 1) {963} | PROGRAMMING | Editorial Tinkoff Internship Warmup Round 2018 and Codeforces Round #475 (Div. 1 + Div. 2) | 2100 | |
| 1905 | Short Code | data structures dp greedy strings trees | Statement | E | Codeforces Round 476 (Div. 2) [Thanks, Telegram!] {965} | PROGRAMMING | Analysis of Codeforces Round #476 (Div. 2) [Thanks, Telegram!] | 2500 | |
| 7377 | Kuro and Walking Route | dfs and similar trees | Statement | C | Codeforces Round 482 (Div. 2) {979} | PROGRAMMING | Codeforces Round #482 (Div. 2) Editorial | 1600 | |
| 2193 | 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 |
| 2125 | The Number Games | data structures greedy trees | Statement | E | Codeforces Round 480 (Div. 2) {980} | PROGRAMMING | Tutorial | 2300 | |
| 216 | Cactus to Tree | dp graphs trees | Statement | F | Codeforces Round 480 (Div. 2) {980} | PROGRAMMING | Tutorial | 2900 | |
| 6890 | Useful Decomposition | implementation trees | Statement | C | Avito Code Challenge 2018 {981} | PROGRAMMING | 59713 | 1400 | |
| 16139 | Cut 'em all! | dfs and similar dp graphs greedy trees | Statement | C | Codeforces Round 484 (Div. 2) {982} | PROGRAMMING | Editorial | 1500 | |
| 2526 | Shark | brute force data structures dsu trees | Statement | D | Codeforces Round 484 (Div. 2) {982} | PROGRAMMING | Editorial | 1900 | |
| 1203 | NN country | binary search data structures trees | Statement | E | Codeforces Round 483 (Div. 1) [Thanks, Botan Investments and Victor Shaburov!] {983} | PROGRAMMING | Codeforces Round #483 [Thanks, Botan Investments and Victor Shaburov!] Editoral | 2700 | |
| 911 | Prince's Problem | brute force data structures math number theory trees | Statement | E | Codeforces Round 485 (Div. 1) {986} | PROGRAMMING | Codeforces Round #485 Editorial | 2900 | |
| 2342 | GCD Counting | divide and conquer dp dsu number theory trees | Statement | G | Educational Codeforces Round 45 (Rated for Div. 2) {990} | PROGRAMMING | Educational Codeforces Round 45 Editorial | 2400 | |
| 1058 | Flow Control | dfs and similar dp greedy trees | Statement | F | Educational Codeforces Round 45 (Rated for Div. 2) {990} | PROGRAMMING | Educational Codeforces Round 45 Editorial | 2500 | |
| 1658 | Cowmpany Cowmpensation | combinatorics dp math trees | Statement | F | Codeforces Round 492 (Div. 1) [Thanks, uDebug!] {995} | PROGRAMMING | Editorial for Codeforces Round #492 [Thanks u-Debug!] | 2700 | |
| 517 | Cycles in product | combinatorics divide and conquer trees | Statement | D | Codeforces Round 493 (Div. 1) {997} | PROGRAMMING | 60357 | 2800 | |
| 14446 | Cutting | dp greedy sortings | Statement | B | Codeforces Round 493 (Div. 2) {998} | PROGRAMMING | Codeforces Round #493 — Editorial | 1200 | |
| 6595 | We Need More Bosses | dfs and similar graphs trees | Statement | E | Educational Codeforces Round 46 (Rated for Div. 2) {1000} | PROGRAMMING | 60288 | 2100 | |
| 725 | Two-Paths | data structures dp trees | Statement | G | Educational Codeforces Round 46 (Rated for Div. 2) {1000} | PROGRAMMING | 60288 | 2800 | |
| 1247 | Sonya and Ice Cream | binary search data structures dp greedy shortest paths trees | Statement | E | Codeforces Round 495 (Div. 2) {1004} | PROGRAMMING | 60443 | 2400 | |
| 11712 | Military Problem | dfs and similar graphs trees | Statement | E | Codeforces Round 498 (Div. 3) {1006} | PROGRAMMING | 60672 | 1600 | |
| 323 | Ants | 2-sat data structures trees | Statement | D | Codeforces Round 497 (Div. 1) {1007} | PROGRAMMING | Editorial for Codeforces Round #497 by Skyglow | 3200 | |
| 7866 | Dominant Indices | data structures dsu trees | Statement | F | Educational Codeforces Round 47 (Rated for Div. 2) {1009} | PROGRAMMING | 60630 | 2300 | |
| 2585 | Mars rover | dfs and similar graphs implementation trees | Statement | D | Codeforces Round 499 (Div. 1) {1010} | PROGRAMMING | 60851 | 2100 | |
| 264 | Tree | fft graphs trees | Statement | F | Codeforces Round 499 (Div. 1) {1010} | PROGRAMMING | 60851 | 3400 | |
| 1030 | Road Projects | dfs and similar dp trees | Statement | F | Educational Codeforces Round 48 (Rated for Div. 2) {1016} | PROGRAMMING | Разбор Educational Codeforces Round 48 | 2600 | |
| 407 | Raining season | data structures divide and conquer trees | Statement | E | Codeforces Round 503 (by SIS, Div. 1) {1019} | PROGRAMMING | 61161 | 3200 | |
| 1010 | 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 | |
| 189 | Pisces | data structures flows trees | Statement | G | Codeforces Round 504 (rated, Div. 1 + Div. 2, based on VK Cup 2018 Final) {1023} | PROGRAMMING | Codeforces Round 504 Editorial | 3300 | |
| 4150 | Recovering BST | brute force dp math number theory trees | Statement | D | Codeforces Round 505 (rated, Div. 1 + Div. 2, based on VK Cup 2018 Final) {1025} | PROGRAMMING | Codeforces Round #505 Editorial | 2000 | |
| 1148 | Vasya and Maximum Matching | dp trees | Statement | F | Technocup 2019 - Elimination Round 3 {1032} | PROGRAMMING | Codeforces Round #522 and Technocup 2019 Elimination Round 3 Editorial | 2600 | |
| 999 | Region Separation | combinatorics dp number theory trees | Statement | C | Codeforces Round 511 (Div. 1) {1034} | PROGRAMMING | Codeforces Round #511 Editorial | 2900 | |
| 19324 | Valid BFS? | dfs and similar graphs shortest paths trees | Statement | D | Manthan, Codefest 18 (rated, Div. 1 + Div. 2) {1037} | PROGRAMMING | Tutorial | 1700 | |
| 2334 | You Are Given a Tree | data structures dp trees | Statement | D | Codeforces Round 507 (Div. 1, based on Olympiad of Metropolises) {1039} | PROGRAMMING | 61668 | 2700 | |
| 1492 | Leaf Sets | data structures dfs and similar dsu graphs greedy sortings trees | Statement | F | Codeforces Round 510 (Div. 2) {1042} | PROGRAMMING | Tutorial | 2400 | |
| 1715 | Intersecting Subtrees | dfs and similar interactive trees | Statement | B | Lyft Level 5 Challenge 2018 - Final Round {1044} | PROGRAMMING | Lyft Level 5 Challenge 2018 — Final Round — Editorial | 1900 | |
| 830 | Hyperspace Highways | dfs and similar graphs trees | Statement | C | Bubble Cup 11 - Finals [Online Mirror, Div. 1] {1045} | PROGRAMMING | Tutorial (PDF) | 2500 | |
| 868 | Interstellar battle | math probabilities trees | Statement | D | Bubble Cup 11 - Finals [Online Mirror, Div. 1] {1045} | PROGRAMMING | Tutorial (PDF) | 2600 | |
| 575 | Last chance | data structures flows graph matchings trees | Statement | A | Bubble Cup 11 - Finals [Online Mirror, Div. 1] {1045} | PROGRAMMING | E | 2800 | |
| 210 | Moonwalk challenge | data structures strings trees | Statement | J | Bubble Cup 11 - Finals [Online Mirror, Div. 1] {1045} | PROGRAMMING | E | 3000 | |
| 3778 | The Shortest Statement | graphs shortest paths trees | Statement | F | Educational Codeforces Round 51 (Rated for Div. 2) {1051} | PROGRAMMING | Educational Codeforces Round 51 Editorial | 2300 | |
| 246 | Euler tour | constructive algorithms trees | Statement | E | Codeforces Round 512 (Div. 1, based on Technocup 2019 Elimination Round 1) {1053} | PROGRAMMING | Сodeforces Round 512 (and Technocup — Elimination Round 1) Editorial | 3500 | |
| 613 | Tree and XOR | strings trees | Statement | F | Mail.Ru Cup 2018 Round 2 {1055} | PROGRAMMING | Mail.Ru Cup 2018 Round 2 — analysis | 2800 | |
| 6747 | Decorate Apple Tree | constructive algorithms dfs and similar dp graphs greedy sortings trees | Statement | D | Mail.Ru Cup 2018 Round 3 {1056} | PROGRAMMING | Mail.Ru Cup 2018 Round 3 Editorial | 1600 | |
| 7543 | Bmail Computer Network | *special dfs and similar trees | Statement | A | Mail.Ru Cup 2018 - Practice Round {1057} | PROGRAMMING | 1700 | ||
| 1626 | Split the Tree | binary search data structures dp greedy trees | Statement | E | Codeforces Round 514 (Div. 2) {1059} | PROGRAMMING | Codeforces Round #514 (Div. 2) Editorial | 2400 | |
| 3527 | Sergey and Subway | dfs and similar dp trees | Statement | E | Codeforces Round 513 by Barcelona Bootcamp (rated, Div. 1 + Div. 2) {1060} | PROGRAMMING | User editorial for Codeforces Round 513 by Barcelona Bootcamp (rated, Div. 1 + Div. 2) | 2000 | |
| 2092 | Company | binary search data structures dfs and similar greedy trees | Statement | E | Codeforces Round 520 (Div. 2) {1062} | PROGRAMMING | Tutorial | 2300 | |
| 1329 | Up and Down the Tree | dfs and similar dp trees | Statement | F | Educational Codeforces Round 52 (Rated for Div. 2) {1065} | PROGRAMMING | Educational Codeforces Round 52 Editorial | 2500 | |
| 555 | Random Forest Rank | dp graph matchings math trees | Statement | E | Codeforces Round 518 (Div. 1) [Thanks, Mail.Ru!] {1067} | PROGRAMMING | Tutorial | 2800 | |
| 594 | Choosing Two Paths | dfs and similar dp greedy trees | Statement | F | Educational Codeforces Round 53 (Rated for Div. 2) {1073} | PROGRAMMING | 62742 | 2800 | |
| 4161 | Vasya and a Tree | data structures trees | Statement | E | Educational Codeforces Round 54 (Rated for Div. 2) {1076} | PROGRAMMING | E | 1900 | |
| 551 | Speed Dial | dp strings trees | Statement | F | Educational Codeforces Round 55 (Rated for Div. 2) {1082} | PROGRAMMING | 63544 | 2900 | |
| 6320 | The Fair Nut and the Best Path | data structures dp trees | Statement | A | Codeforces Round 526 (Div. 1) {1083} | PROGRAMMING | 63753 | 1800 | |
| 1118 | Max Mex | data structures trees | Statement | C | Codeforces Round 526 (Div. 1) {1083} | PROGRAMMING | 63753 | 2800 | |
| 5656 | Connect Three | implementation math | Statement | C | Technocup 2019 - Elimination Round 4 {1085} | PROGRAMMING | Technocup 2019 — Elimination Round 4 + Codeforces Round 528: editorial | 1600 | |
| 5918 | Minimum Diameter Tree | constructive algorithms implementation trees | Statement | D | Technocup 2019 - Elimination Round 4 {1085} | PROGRAMMING | Technocup 2019 — Elimination Round 4 + Codeforces Round 528: editorial | 1700 | |
| 318 | Forest Fires | math | Statement | F | Codeforces Round 528 (Div. 1, based on Technocup 2019 Elimination Round 4) {1086} | PROGRAMMING | Technocup 2019 — Elimination Round 4 + Codeforces Round 528: editorial | 3400 | |
| 1620 | Ehab and a component choosing problem | dp greedy math trees | Statement | E | Codeforces Round 525 (Div. 2) {1088} | PROGRAMMING | Codeforces round #525 editorial | 2400 | |
| 597 | Ehab and a weird weight formula | data structures trees | Statement | F | Codeforces Round 525 (Div. 2) {1088} | PROGRAMMING | Codeforces round #525 editorial | 3000 | |
| 11018 | Tree with Maximum Cost | dfs and similar dp trees | Statement | F | Codeforces Round 527 (Div. 3) {1092} | PROGRAMMING | Codeforces Round #527 (Div. 3) Editorial | 2100 | |
| 1994 | Minimal Diameter Forest | constructive algorithms dfs and similar greedy trees | Statement | E | Codeforces Round 527 (Div. 3) {1092} | PROGRAMMING | Codeforces Round #527 (Div. 3) Editorial | 2500 | |
| 1059 | Vladislav and a Great Legend | combinatorics dp trees | Statement | G | Hello 2019 {1097} | PROGRAMMING | 64310 | 2900 | |
| 9580 | Sum in the tree | constructive algorithms dfs and similar greedy trees | Statement | A | Codeforces Round 530 (Div. 1) {1098} | PROGRAMMING | 64331 | 1600 | |
| 1162 | Construct a tree | binary search constructive algorithms dfs and similar graphs greedy trees | Statement | C | Codeforces Round 530 (Div. 1) {1098} | PROGRAMMING | 64331 | 2300 | |
| 1052 | Cookies | binary search data structures dfs and similar dp games trees | Statement | F | Codeforces Round 530 (Div. 2) {1099} | PROGRAMMING | E | 2300 | |
| 5452 | GCD Counting | data structures dfs and similar dp number theory trees | Statement | D | Educational Codeforces Round 58 (Rated for Div. 2) {1101} | PROGRAMMING | 64483 | 2000 | |
| 1507 | Sasha and Interesting Fact from Graph Theory | brute force combinatorics dp math trees | Statement | D | Codeforces Round 539 (Div. 1) {1109} | PROGRAMMING | Codeforces Round #539 Editorial | 2600 | |
| 368 | Sasha and Algorithm of Silence's Sounds | data structures trees | Statement | F | Codeforces Round 539 (Div. 1) {1109} | PROGRAMMING | Codeforces Round #539 Editorial | 3200 | |
| 2075 | Nearest Leaf | data structures trees | Statement | F | Codeforces Global Round 1 {1110} | PROGRAMMING | The Editorial of the First Codeforces Global Round | 2600 | |
| 754 | Tree-Tac-Toe | constructive algorithms games trees | Statement | G | Codeforces Global Round 1 {1110} | PROGRAMMING | The Editorial of the First Codeforces Global Round | 3000 | |
| 1121 | 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 | |
| 6741 | Tree Cutting (Easy Version) | dfs and similar trees | Statement | F1 | Codeforces Round 540 (Div. 3) {1118} | PROGRAMMING | 65396 | 1800 | |
| 651 | Tree Cutting (Hard Version) | combinatorics dfs and similar dp trees | Statement | F2 | Codeforces Round 540 (Div. 3) {1118} | PROGRAMMING | 65396 | 2700 | |
| 876 | Niyaz and Small Degrees | data structures dp trees | Statement | F | Codeforces Global Round 2 {1119} | PROGRAMMING | Codeforces Global Round 2 Editorial | 2900 | |
| 1782 | 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 | |
| 572 | Legendary Tree | binary search interactive trees | Statement | E | Codeforces Round 542 [Alex Lopashev Thanks-Round] (Div. 1) {1129} | PROGRAMMING | 65520 | 3000 | |
| 1239 | Greedy Subsequences | data structures dp trees | Statement | G | Educational Codeforces Round 61 (Rated for Div. 2) {1132} | PROGRAMMING | T | 2600 | |
| 3839 | 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 | |
| 527 | Matches Are Not a Child's Play | data structures trees | Statement | F | Codeforces Round 545 (Div. 1) {1137} | PROGRAMMING | Codeforces Round #545 – Editorial | 3300 | |
| 16881 | Edgy Trees | dfs and similar dsu graphs math trees | Statement | C | Codeforces Round 548 (Div. 2) {1139} | PROGRAMMING | Codeforces Round #548 Editorial | 1500 | |
| 619 | Double Tree | data structures divide and conquer shortest paths trees | Statement | G | Educational Codeforces Round 62 (Rated for Div. 2) {1140} | PROGRAMMING | Educational Codeforces Round 62 Editorial | 2900 | |
| 2556 | Privatization of Roads in Treeland | binary search constructive algorithms dfs and similar graphs greedy trees | Statement | G | Codeforces Round 547 (Div. 3) {1141} | PROGRAMMING | 66062 | 2500 | |
| 3831 | Lynyrd Skynyrd | data structures dfs and similar dp math trees | Statement | B | Codeforces Round 549 (Div. 1) {1142} | PROGRAMMING | Codeforces Round #549 Editorial | 2300 | |
| 17935 | Queen | dfs and similar trees | Statement | C | Codeforces Round 549 (Div. 2) {1143} | PROGRAMMING | Codeforces Round #549 Editorial | 1400 | |
| 1341 | Leaf Partition | dp trees | Statement | F | Forethought Future Cup - Elimination Round {1146} | PROGRAMMING | 66639 | 2400 | |
| 1678 | Tree Generator™ | data structures implementation trees | Statement | C | Codeforces Round 556 (Div. 1) {1149} | PROGRAMMING | 66783 | 2900 | |
| 2582 | Neko and Aki's Prank | dp greedy trees | Statement | D | Codeforces Round 554 (Div. 2) {1152} | PROGRAMMING | T | 2000 | |
| 5571 | Serval and Rooted Tree | binary search dfs and similar dp greedy trees | Statement | D | Codeforces Round 551 (Div. 2) {1153} | PROGRAMMING | Editorial | 1800 | |
| 4689 | 0-1-Tree | dfs and similar divide and conquer dp dsu trees | Statement | D | Educational Codeforces Round 64 (Rated for Div. 2) {1156} | PROGRAMMING | 66827 | 2300 | |
| 230 | Strange device | binary search interactive math trees | Statement | E | Codeforces Round 559 (Div. 1) {1158} | PROGRAMMING | 66993 | 3300 | |
| 441 | Anagram Paths | dp implementation trees | Statement | D | Codeforces Round 562 (Div. 1) {1168} | PROGRAMMING | Codeforces Round #562 — Editorial | 2900 | |
| 4426 | Nauuo and Circle | combinatorics dfs and similar dp trees | Statement | B | Codeforces Round 564 (Div. 1) {1172} | PROGRAMMING | Codeforces Round #564 Editorial | 2000 | |
| 1982 | Ehab and the Big Finale | constructive algorithms divide and conquer graphs implementation interactive trees | Statement | F | Codeforces Round 563 (Div. 2) {1174} | PROGRAMMING | Codeforces round #563 editorial | 2300 | |
| 4576 | Minimal Segment Cover | data structures dfs and similar divide and conquer dp greedy implementation trees | Statement | E | Educational Codeforces Round 66 (Rated for Div. 2) {1175} | PROGRAMMING | Editorial | 2200 | |
| 13701 | Cover it! | dfs and similar dsu graphs shortest paths trees | Statement | E | Codeforces Round 565 (Div. 3) {1176} | PROGRAMMING | 67598 | 1700 | |
| 2469 | Serge and Dining Room | binary search data structures graph matchings greedy implementation math trees | Statement | C | Codeforces Round 569 (Div. 1) {1179} | PROGRAMMING | Editorial of Round #569 | 2400 | |
| 1037 | Fedor Runs for President | data structures dp trees | Statement | D | Codeforces Round 569 (Div. 1) {1179} | PROGRAMMING | Editorial of Round #569 | 2600 | |
| 2830 | Irrigation | binary search data structures implementation sortings trees two pointers | Statement | D | Codeforces Round 567 (Div. 2) {1181} | PROGRAMMING | Editorial of Codeforces Round #567 (based on All-Russian olympiad in the name of Keldysh) | 2100 | |
| 1019 | Complete Mirror | constructive algorithms dfs and similar dp hashing implementation trees | Statement | D | Codeforces Round 566 (Div. 2) {1182} | PROGRAMMING | 67614 | 2500 | |
| 1867 | Daleks' Invasion (easy) | graphs trees | Statement | E1 | Helvetic Coding Contest 2019 online mirror (teams allowed, unrated) {1184} | PROGRAMMING | helvetic-coding-contest-2019-editorial.pdf | 2000 | |
| 1062 | Daleks' Invasion (medium) | dfs and similar graphs shortest paths trees | Statement | E2 | Helvetic Coding Contest 2019 online mirror (teams allowed, unrated) {1184} | PROGRAMMING | helvetic-coding-contest-2019-editorial.pdf | 2200 | |
| 669 | 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 | |
| 11444 | Tree Painting | dfs and similar dp trees | Statement | E | Educational Codeforces Round 67 (Rated for Div. 2) {1187} | PROGRAMMING | Разбор Educational Codeforces Round 67 | 2000 | |
| 8961 | Add on a Tree | trees | Statement | A1 | Codeforces Round 572 (Div. 1) {1188} | PROGRAMMING | Editorial of Codeforces Round #572 | 1600 | |
| 1297 | Add on a Tree: Revolution | constructive algorithms dfs and similar implementation trees | Statement | A2 | Codeforces Round 572 (Div. 1) {1188} | PROGRAMMING | Editorial of Codeforces Round #572 | 2500 | |
| 1583 | Dynamic Diameter | *special data structures dfs and similar divide and conquer trees | Statement | B | CEOI 2019 day 1 online mirror (unrated, IOI format) {1192} | PROGRAMMING | E | ||
| 510 | Magic Tree | *special data structures dp trees | Statement | B | CEOI 2019 day 2 online mirror (unrated, IOI format) {1193} | PROGRAMMING | T | ||
| 769 | Almost All | constructive algorithms trees | Statement | D | Codeforces Round 580 (Div. 1) {1205} | PROGRAMMING | 69158 | 2800 | |
| 1236 | Indie Album | data structures dfs and similar hashing string suffix structures strings trees | Statement | G | Educational Codeforces Round 71 (Rated for Div. 2) {1207} | PROGRAMMING | Educational Codeforces Round 71 Editorial | 2600 | |
| 189 | Red Blue Tree | data structures implementation trees | Statement | H | Manthan, Codefest 19 (open for everyone, rated, Div. 1 + Div. 2) {1208} | PROGRAMMING | 69357 | 3500 | |
| 1367 | 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 | |
| 3601 | Kamil and Making a Stream | math number theory trees | Statement | C | Dasha Code Championship - SPb Finals Round (only for onsite-finalists) {1210} | PROGRAMMING | Dasha Code Championship Finals and Mirror Round 588 Editorial | 2100 | |
| 84 | King's Path | *special math trees | Statement | G | Kotlin Heroes: Episode 2 {1211} | PROGRAMMING | Kotlin Heroes: Episode 2 Editorial | 2500 | |
| 57 | Road Repair in Treeland | *special binary search dp trees | Statement | H | Kotlin Heroes: Episode 2 {1211} | PROGRAMMING | Kotlin Heroes: Episode 2 Editorial | 3000 | |
| 9634 | Path Queries | divide and conquer dsu graphs sortings trees | Statement | G | Codeforces Round 582 (Div. 3) {1213} | PROGRAMMING | Codeforces Round #582 (Div. 3) Editorial | 2000 | |
| 2866 | Petya and Construction Set | constructive algorithms graphs math sortings trees | Statement | E | Codeforces Round 583 (Div. 1 + Div. 2, based on Olympiad of Metropolises) {1214} | PROGRAMMING | Tutorial | 2000 | |
| 461 | Tiles Placement | constructive algorithms dfs and similar trees | Statement | H | Codeforces Round 583 (Div. 1 + Div. 2, based on Olympiad of Metropolises) {1214} | PROGRAMMING | Tutorial | 2700 | |
| 725 | 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 | |
| 3012 | 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 | |
| 856 | Gardener Alex | binary search data structures | Statement | F | Codeforces Round 586 (Div. 1 + Div. 2) {1220} | PROGRAMMING | Codeforces Round #586 Editorial | 2600 | |
| 2902 | Paint the Tree | dp sortings trees | Statement | E | Technocup 2020 - Elimination Round 1 {1223} | PROGRAMMING | Сodeforces Round 591 (and Technocup 2020 — Elimination Round 1) Editorial | 2200 | |
| 276 | Wooden Raft | binary search math number theory | Statement | G | Technocup 2020 - Elimination Round 1 {1223} | PROGRAMMING | Сodeforces Round 591 (and Technocup 2020 — Elimination Round 1) Editorial | 3100 | |
| 995 | Tree Factory | constructive algorithms greedy trees | Statement | F | Technocup 2020 - Elimination Round 2 {1225} | PROGRAMMING | 70898 | 2500 | |
| 1650 | Arson In Berland Forest | binary search graphs graphs shortest paths | Statement | E | Technocup 2020 - Elimination Round 3 {1227} | PROGRAMMING | Разбор задач №2 | 2200 | |
| 479 | One Node is Gone | constructive algorithms implementation trees | Statement | F | Codeforces Round 589 (Div. 2) {1228} | PROGRAMMING | 70162 | 2700 | |
| 1523 | Balanced Binary Search Trees | dp math | Statement | E | Codeforces Global Round 5 {1237} | PROGRAMMING | T | 2400 | |
| 2078 | The Maximum Subtree | dfs and similar dp graphs trees | Statement | F | Educational Codeforces Round 74 (Rated for Div. 2) {1238} | PROGRAMMING | Educational Codeforces Round 74 Editorial | 2300 | |
| 9397 | 0-1 MST | dfs and similar dsu graphs sortings | Statement | B | Codeforces Round 599 (Div. 1) {1242} | PROGRAMMING | Codeforces Round #599 Editorial | 1900 | |
| 8321 | Paint the Tree | brute force constructive algorithms dp graphs implementation trees | Statement | D | Codeforces Round 592 (Div. 2) {1244} | PROGRAMMING | Codeforces Round #592 (Div. 2) Tutorial | 1700 | |
| 9758 | Shichikuji and Power Grid | dsu graphs greedy shortest paths trees | Statement | D | Codeforces Round 597 (Div. 2) {1245} | PROGRAMMING | Codeforces Round #597 (Div. 2) Editorial | 1900 | |
| 18049 | Grow The Tree | greedy math sortings | Statement | B | Codeforces Round 594 (Div. 2) {1248} | PROGRAMMING | Editorial of Codeforces Round #594 (on the problems of Moscow Team Olympiad) | 900 | |
| 2758 | Maximum Weight Subset | dp trees | Statement | F | Codeforces Round 595 (Div. 3) {1249} | PROGRAMMING | Codeforces Round #595 (Div. 3) Editorial | 2500 | |
| 1086 | Regular Forestation | hashing trees | Statement | F | 2019-2020 ICPC, Asia Jakarta Regional Contest (Online Mirror, ICPC Rules, Teams Preferred) {1252} | PROGRAMMING | T | 2500 | |
| 588 | Cleaning Robots | dp trees | Statement | B | 2019-2020 ICPC, Asia Jakarta Regional Contest (Online Mirror, ICPC Rules, Teams Preferred) {1252} | PROGRAMMING | T | 2600 | |
| 415 | Find String in a Grid | data structures dp strings trees | Statement | D | 2019-2020 ICPC, Asia Jakarta Regional Contest (Online Mirror, ICPC Rules, Teams Preferred) {1252} | PROGRAMMING | T | 2900 | |
| 2267 | Cheap Robot | binary search dsu graphs shortest paths trees | Statement | F | Codeforces Round 600 (Div. 2) {1253} | PROGRAMMING | Editorial | 2600 | |
| 1567 | Tree Queries | data structures probabilities trees | Statement | D | Codeforces Round 601 (Div. 1) {1254} | PROGRAMMING | Codeforces Round #601 Editorial | 2600 | |
| 366 | Send Tree to Charlie | combinatorics dfs and similar dsu trees | Statement | E | Codeforces Round 601 (Div. 1) {1254} | PROGRAMMING | Codeforces Round #601 Editorial | 3200 | |
| 648 | Colored Tree | data structures trees | Statement | F | Educational Codeforces Round 77 (Rated for Div. 2) {1260} | PROGRAMMING | Educational Codeforces Round 77 Editorial | 2700 | |
| 957 | 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 | |
| 676 | Tree Elimination | dp trees | Statement | D | Codeforces Round 606 (Div. 1, based on Technocup 2020 Elimination Round 4) {1276} | PROGRAMMING | Technocup 2020 — Elimination Round 4 + Codeforces Round 606: Editorial | 2600 | |
| 4349 | 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 | |
| 2049 | Tests for problem D | constructive algorithms dfs and similar divide and conquer trees | Statement | E | Educational Codeforces Round 78 (Rated for Div. 2) {1278} | PROGRAMMING | Educational Codeforces Round 78 Editorial | 2200 | |
| 3044 | Jeremy Bearimy | dfs and similar graphs greedy trees | Statement | C | Codeforces Round 607 (Div. 1) {1280} | PROGRAMMING | Codeforces Round #607 Editorial | 2000 | |
| 1244 | Miss Punyverse | dp greedy trees | Statement | D | Codeforces Round 607 (Div. 1) {1280} | PROGRAMMING | Codeforces Round #607 Editorial | 2700 | |
| 9580 | Christmas Trees | graphs greedy shortest paths | Statement | D | Codeforces Round 611 (Div. 3) {1283} | PROGRAMMING | Codeforces Round #611 (Div. 3) Editorial | 1800 | |
| 2049 | DIY Garland | constructive algorithms greedy trees | Statement | F | Codeforces Round 611 (Div. 3) {1283} | PROGRAMMING | Codeforces Round #611 (Div. 3) Editorial | 2400 | |
| 413 | New Year and Social Network | data structures graph matchings graphs math trees | Statement | F | Hello 2020 {1284} | PROGRAMMING | Hello 2020 Editorial | 3100 | |
| 8643 | Dr. Evil Underscores | bitmasks brute force dfs and similar divide and conquer dp greedy strings trees | Statement | D | Codeforces Round 613 (Div. 2) {1285} | PROGRAMMING | Codeforces Round #613 (Div. 2) Editorial | 1800 | |
| 2005 | 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 | |
| 5511 | 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 | |
| 671 | Cartesian Tree | data structures | Statement | E | Codeforces Round 616 (Div. 1) {1290} | PROGRAMMING | 3000.0 | Codeforces Round #616 Editorial | 3200 |
| 2255 | Xenon's Attack on the Gangs | combinatorics dfs and similar dp greedy trees | Statement | C | Codeforces Round 614 (Div. 1) {1292} | PROGRAMMING | 1250.0 | Codeforces Round #614 Editorial | 2300 |
| 977 | Chaotic V. | dp graphs greedy math number theory trees | Statement | D | Codeforces Round 614 (Div. 1) {1292} | PROGRAMMING | 1750.0 | Codeforces Round #614 Editorial | 2700 |
| 6940 | Three Paths on a Tree | dfs and similar dp greedy trees | Statement | F | Codeforces Round 615 (Div. 3) {1294} | PROGRAMMING | Codeforces Round #615 (Div. 3) Editorial | 2100 | |
| 3099 | Berland Beauty | constructive algorithms dfs and similar greedy sortings trees | Statement | F | Codeforces Round 617 (Div. 3) {1296} | PROGRAMMING | Codeforces Round #617 (Div. 3) Editorial | 2400 | |
| 219 | Modernization of Treeland | *special dfs and similar trees | Statement | E | Kotlin Heroes: Episode 3 {1297} | PROGRAMMING | Kotlin Heroes: Episode 3 Editorial | ||
| 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 |
| 1019 | Sum of Prefix Sums | data structures divide and conquer geometry trees | Statement | G | Educational Codeforces Round 82 (Rated for Div. 2) {1303} | PROGRAMMING | Educational Codeforces Round 82 | 2700 | |
| 5914 | 1-Trees and Queries | data structures dfs and similar shortest paths trees | Statement | E | Codeforces Round 620 (Div. 2) {1304} | PROGRAMMING | 2000.0 | Codeforces Round #620 (Div. 2) Editorial | 2000 |
| 5373 | Kuroni and the Celebration | constructive algorithms dfs and similar graphs interactive trees | Statement | D | Ozon Tech Challenge 2020 (Div.1 + Div.2, Rated, T-shirts + prizes!) {1305} | PROGRAMMING | 1750.0 | Ozon Tech Challenge 2020 Editorial | 1900 |
| 679 | Cow and Vacation | dfs and similar dsu trees | Statement | F | Codeforces Round 621 (Div. 1 + Div. 2) {1307} | PROGRAMMING | 3000.0 | Codeforces Round #621 (Div. 1 + Div. 2) Editorial | 3200 |
| 2731 | Construct the Binary Tree | brute force constructive algorithms dfs and similar trees | Statement | E | Codeforces Round 624 (Div. 3) {1311} | PROGRAMMING | 74224 | 2400 |