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 |
|---|---|---|---|---|---|---|---|---|---|
| 4491 | How many trees? | combinatorics divide and conquer dp | Statement | D | Codeforces Beta Round 9 (Div. 2 Only) {9} | PROGRAMMING | Codeforces Beta Round #9 tutorial | 2000 | |
| 837 | Polo the Penguin and Trees | combinatorics dfs and similar trees | Statement | D | Codeforces Round 177 (Div. 1) {288} | PROGRAMMING | Codeforces Round #177, editorial | 2300 | |
| 430 | Ksenia and Combinatorics | combinatorics dp | Statement | E | Codeforces Round 224 (Div. 2) {382} | PROGRAMMING | Codeforces Round #224 (Div. 2) Editorial | 2600 | |
| 2126 | The Child and Binary Tree | combinatorics divide and conquer fft number theory | Statement | E | Codeforces Round 250 (Div. 1) {438} | PROGRAMMING | Tutorial | 3100 | |
| 590 | Random Function and Tree | combinatorics dp trees | Statement | D | Codeforces Round 275 (Div. 1) {482} | PROGRAMMING | Codeforces Round #275 Editorial | 2600 | |
| 3274 | New Year Santa Network | combinatorics dfs and similar graphs trees | Statement | D | Good Bye 2014 {500} | PROGRAMMING | Tutorial 2 | 1900 | |
| 1148 | Famil Door and Roads | combinatorics data structures dfs and similar dp probabilities trees | Statement | E | Codeforces Round 343 (Div. 2) {629} | PROGRAMMING | Editorial of Codeforces Round #343 (Div.2) | 2400 | |
| 520 | Uniformly Branched Trees | combinatorics dp trees | Statement | F | Intel Code Challenge Final Round (Div. 1 + Div. 2, Combined) {724} | PROGRAMMING | Tutorial | 2800 | |
| 478 | Tree nesting | combinatorics graphs trees | Statement | F | Educational Codeforces Round 17 {762} | PROGRAMMING | Tutorial | 2900 | |
| 977 | 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 | |
| 2111 | Desk Disorder | combinatorics dfs and similar dsu graphs trees | Statement | E | MemSQL Start[c]UP 3.0 - Round 1 {859} | PROGRAMMING | Tutorial | 2100 | |
| 277 | 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 | |
| 2264 | 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 | |
| 1603 | 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 | |
| 514 | Cycles in product | combinatorics divide and conquer trees | Statement | D | Codeforces Round 493 (Div. 1) {997} | PROGRAMMING | 60357 | 2800 | |
| 992 | Region Separation | combinatorics dp number theory trees | Statement | C | Codeforces Round 511 (Div. 1) {1034} | PROGRAMMING | Codeforces Round #511 Editorial | 2900 | |
| 1052 | Vladislav and a Great Legend | combinatorics dp trees | Statement | G | Hello 2019 {1097} | PROGRAMMING | 64310 | 2900 | |
| 1499 | 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 | |
| 630 | Tree Cutting (Hard Version) | combinatorics dfs and similar dp trees | Statement | F2 | Codeforces Round 540 (Div. 3) {1118} | PROGRAMMING | 65396 | 2700 | |
| 4403 | Nauuo and Circle | combinatorics dfs and similar dp trees | Statement | B | Codeforces Round 564 (Div. 1) {1172} | PROGRAMMING | Codeforces Round #564 Editorial | 2000 | |
| 361 | Send Tree to Charlie | combinatorics dfs and similar dsu trees | Statement | E | Codeforces Round 601 (Div. 1) {1254} | PROGRAMMING | Codeforces Round #601 Editorial | 3200 | |
| 2250 | 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 |
| 528 | 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 |
| 233 | Star Trek | *special combinatorics dfs and similar dp games graphs matrices trees | Statement | C | Central-European Olympiad in Informatics, CEOI 2020, Day 1 (IOI, Unofficial Mirror Contest, Unrated) {1402} | PROGRAMMING | Editorial | ||
| 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 | ||
| 810 | Pairs of Paths | combinatorics data structures trees | Statement | F | Codeforces Round 703 (Div. 2) {1486} | PROGRAMMING | 3000.0 | Codeforces Round #703 (Div. 2) Editorial | |
| 1530 | BFS Trees | combinatorics dfs and similar graphs math shortest paths trees | Statement | D | Codeforces Round 706 (Div. 1) {1495} | PROGRAMMING | 2000.0 | Codeforces Round #706 Editorial | |
| 2283 | MEX Tree | combinatorics constructive algorithms data structures dfs and similar math trees | Statement | D | Codeforces Round 721 (Div. 2) {1527} | PROGRAMMING | 2250.0 | Tutorial | 2400 |
| 600 | Mashtali and Hagh Trees | combinatorics dp trees | Statement | E | Codeforces Round 722 (Div. 1) {1528} | PROGRAMMING | 2750.0 | Codeforces Round #722 Editorial | |
| 2983 | Tree Array | brute force combinatorics dp math probabilities trees | Statement | B | Codeforces Round 728 (Div. 1) {1540} | PROGRAMMING | 1250.0 | Tutorial | |
| 2167 | Equidistant Vertices | combinatorics dfs and similar dp trees | Statement | F | Codeforces Round 734 (Div. 3) {1551} | PROGRAMMING | Editorial for Codeforces Round #734 (Div.3) | ||
| 1276 | Mathematics Curriculum | combinatorics dp trees | Statement | B | Codeforces Round 745 (Div. 1) {1580} | PROGRAMMING | 1000.0 | Codeforces Round #745 Editorial | 2600 |
| 2477 | Star MST | combinatorics dp math | Statement | E | Educational Codeforces Round 125 (Rated for Div. 2) {1657} | PROGRAMMING | 101161 | ||
| 803 | Centroid Probabilities | combinatorics dp fft math | Statement | E | Codeforces Round 783 (Div. 1) {1667} | PROGRAMMING | 2750.0 | Codeforces Round #783 Editorial | 3000 |
| 3162 | Preorder | combinatorics divide and conquer dp dsu hashing trees | Statement | E | Educational Codeforces Round 127 (Rated for Div. 2) {1671} | PROGRAMMING | 102181 | ||
| 1130 | K-Set Tree | combinatorics dfs and similar dp math trees | Statement | F | CodeCraft-22 and Codeforces Round 795 (Div. 2) {1691} | PROGRAMMING | 2750.0 | Editorial for CodeCraft-22 and Codeforces Round #795 (Div. 2) | |
| 889 | Partial Virtual Trees | combinatorics dp math trees | Statement | D | Codeforces Round 808 (Div. 1) {1707} | PROGRAMMING | 1750.0 | 104930 | |
| 595 | Electrical Efficiency | combinatorics data structures dp number theory trees | Statement | E | COMPFEST 14 - Preliminary Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1725} | PROGRAMMING | Tutorial | ||
| 295 | Imitating the Key Tree | combinatorics dsu trees | Statement | I | COMPFEST 14 - Preliminary Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1725} | PROGRAMMING | Tutorial | ||
| 846 | Tree Sum | combinatorics trees | Statement | E | Codeforces Round 838 (Div. 2) {1762} | PROGRAMMING | 2500.0 | Codeforces Round #838 (Div. 2) Editorial | |
| 1607 | Koxia and Tree | combinatorics dp math probabilities trees | Statement | E | Good Bye 2022: 2023 is NEAR {1770} | PROGRAMMING | 2000.0 | Good Bye 2022 -- Editorial | |
| 603 | Segment Covering | brute force combinatorics constructive algorithms data structures trees | Statement | G | Polynomial Round 2022 (Div. 1 + Div. 2, Rated, Prizes!) {1774} | PROGRAMMING | 3250.0 | Polynomial Round 2022 (Div. 1 + Div. 2) Editorial | |
| 4660 | Score of a Tree | bitmasks combinatorics dfs and similar dp probabilities trees | Statement | D | Codeforces Round 845 (Div. 2) and ByteRace 2023 {1777} | PROGRAMMING | 2000.0 | Codeforces Round #845 (Div. 2) and ByteRace 2023 Editorial | |
| 1312 | Bracket Insertion | brute force combinatorics constructive algorithms dp math trees | Statement | F | VK Cup 2022 - Отборочный раунд (Engine) {1781} | PROGRAMMING | 3250.0 | Tutorial | |
| 935 | Timber | combinatorics dp fft math | Statement | F | Educational Codeforces Round 147 (Rated for Div. 2) {1821} | PROGRAMMING | 115296 | ||
| 5971 | LuoTianyi and the Floating Islands (Easy Version) | combinatorics math probabilities trees | Statement | B1 | Codeforces Round 872 (Div. 1) {1824} | PROGRAMMING | 500.0 | CodeForces Round 872(Div. 1&2) Editorial | 1800 |
| 3340 | LuoTianyi and the Floating Islands (Hard Version) | combinatorics dfs and similar math probabilities trees | Statement | B2 | Codeforces Round 872 (Div. 1) {1824} | PROGRAMMING | 750.0 | CodeForces Round 872(Div. 1&2) Editorial | 2300 |
| 2513 | Playoff Fixing | combinatorics trees | Statement | E | Educational Codeforces Round 149 (Rated for Div. 2) {1837} | PROGRAMMING | 116752 | ||
| 21586 | Apple Tree | combinatorics dfs and similar dp trees | Statement | D | Codeforces Round 881 (Div. 3) {1843} | PROGRAMMING | Codeforces Round #881 (Div. 3) Editorial | ||
| 3035 | Guess Game | bitmasks combinatorics constructive algorithms data structures games math probabilities strings trees | Statement | E | Harbour.Space Scholarship Contest 2023-2024 (Div. 1 + Div. 2) {1864} | PROGRAMMING | 2000.0 | Harbour.Space Scholarship Contest 2023-2024 (Div. 1 + Div. 2) Editorial | |
| 1369 | Travel Plan | combinatorics divide and conquer dp math trees | Statement | C | Codeforces Round 896 (Div. 1) {1868} | PROGRAMMING | 1000.0 | Codeforces Round 896 (Div. 1, Div. 2) Editorial | |
| 1263 | One-X | combinatorics dp math | Statement | E | Codeforces Round 915 (Div. 2) {1905} | PROGRAMMING | 2250.0 | Codeforces Round 915 (Div. 2) Editorial | |
| 5740 | Sasha and a Walk in the City | combinatorics dfs and similar dp math trees | Statement | D | Codeforces Round 926 (Div. 2) {1929} | PROGRAMMING | 2000.0 | Codeforces Round #926 (Div. 2) Editorial. | |
| 2258 | Sasha and the Wedding Binary Search Tree | combinatorics dfs and similar math sortings trees | Statement | F | Codeforces Round 926 (Div. 2) {1929} | PROGRAMMING | 3000.0 | Codeforces Round #926 (Div. 2) Editorial. | |
| 2227 | Fenwick Tree | bitmasks brute force combinatorics data structures dp math trees | Statement | C | Codeforces Round 942 (Div. 1) {1967} | PROGRAMMING | 1250.0 | Tutorial | 2300 |
| 1298 | Splittable Permutations | combinatorics data structures dfs and similar greedy math trees | Statement | E | Educational Codeforces Round 166 (Rated for Div. 2) {1976} | PROGRAMMING | Educational Codeforces Round 166 Editorial | ||
| 2656 | Control of Randomness | combinatorics dfs and similar graphs greedy math probabilities trees | Statement | E | Codeforces Round 992 (Div. 2) {2040} | PROGRAMMING | 2250.0 | Codeforces Round #992 (Div.2) Editorial | |
| 1016 | Nested Segments | combinatorics dp math trees | Statement | E | Codeforces Round 997 (Div. 2) {2056} | PROGRAMMING | 2250.0 | Codeforces Round #997 (Div. 2) Editorial | |
| 924 | Counting Is Not Fun (Hard Version) | combinatorics data structures dfs and similar dsu trees | Statement | F2 | Codeforces Round 1000 (Div. 2) {2063} | PROGRAMMING | 1500.0 | Codeforces Round 1000 (Div. 2) — Editorial | |
| 10995 | Tree Jumps | combinatorics dfs and similar dp trees | Statement | D | Educational Codeforces Round 175 (Rated for Div. 2) {2070} | PROGRAMMING | Video Tutorial | ||
| 794 | LeaFall | combinatorics probabilities trees | Statement | E | Codeforces Round 1007 (Div. 2) {2071} | PROGRAMMING | 2500.0 | Codeforces Round 1007 (Div. 2) Editorial | |
| 1886 | Baggage Claim | combinatorics dsu graphs math trees | Statement | B | Codeforces Round 1021 (Div. 1) {2097} | PROGRAMMING | 1000.0 | 142316 | |
| 153 | Shoo Shatters the Sunshine | combinatorics dp trees | Statement | F | Codeforces Round 1024 (Div. 1) {2101} | PROGRAMMING | 3750.0 | 142788 | |
| 3306 | Tree Colorings | combinatorics dp graphs math trees | Statement | E | Educational Codeforces Round 180 (Rated for Div. 2) {2112} | PROGRAMMING | Educational Codeforces Round 180 — Editorial | ||
| 5907 | Wildflower | combinatorics dfs and similar trees | Statement | F | Codeforces Round 1029 (Div. 3) {2117} | PROGRAMMING | Codeforces Round 1029 (Div. 3) Editorial | ||
| 289 | Tree Parking | combinatorics math trees | Statement | G | Order Capital Round 1 (Codeforces Round 1038, Div. 1 + Div. 2) {2122} | PROGRAMMING | 4000.0 | Order Capital Round 1 (Codeforces Round 1038, Div. 1 + Div. 2) Editorial | |
| 6159 | Root was Built by Love, Broken by Destiny | combinatorics dfs and similar graphs trees | Statement | D | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) {2127} | PROGRAMMING | 2000.0 | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) Editorial | |
| 338 | SubMST | combinatorics graphs trees | Statement | F | Pinely Round 5 (Div. 1 + Div. 2) {2161} | PROGRAMMING | 3250.0 | ||
| 447 | Mosaic Tree | combinatorics dp fft math trees | Statement | F | Codeforces Round 1069 (Div. 1) {2174} | PROGRAMMING | 3500.0 | Codeforces Round 1069 Editorial | |
| 1808 | Conquer or of Forest | combinatorics dfs and similar dsu trees | Statement | F | Good Bye 2025 {2178} | PROGRAMMING | 2750.0 | ||
| 1098 | Jumping Man | combinatorics data structures dp trees | Statement | F | Hello 2026 {2183} | PROGRAMMING | 2750.0 | ||
| 941 | Prufer Vertex | combinatorics dsu number theory probabilities trees | Statement | D | Codeforces Round 1073 (Div. 1) {2190} | PROGRAMMING | 2250.0 | Codeforces Round 1073 (Div. 1, Div. 2) Editorial | |
| 277 | Down the Pivot | combinatorics trees | Statement | G | Codeforces Round 1091 (Div. 2) and CodeCraft 26 {2217} | PROGRAMMING | 3250.0 |