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Solved |
Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 459 | Pentagon | combinatorics graphs matrices | Statement | E | Codeforces Beta Round 48 {51} | PROGRAMMING | 2300 | ||
| 1014 | Ski Base | combinatorics dsu graphs | Statement | C | Codeforces Beta Round 75 (Div. 1 Only) {91} | PROGRAMMING | Analysis Codeforces Beta Round #75 | 2500 | |
| 5358 | Quantity of Strings | combinatorics dfs and similar graphs math | Statement | B | Codeforces Round 107 (Div. 1) {150} | PROGRAMMING | Tutorial | 1800 | |
| 2070 | Clues | combinatorics graphs | Statement | D | Codeforces Round 110 (Div. 1) {156} | PROGRAMMING | Codeforces Round 110 — Разбор задач | 2400 | |
| 1783 | Triangles | combinatorics graphs math | Statement | C | Codeforces Round 142 (Div. 1) {229} | PROGRAMMING | Codeforces Round #142 Problem Analysis | 2100 | |
| 1301 | Dima and Horses | combinatorics constructive algorithms graphs | Statement | E | Codeforces Round 167 (Div. 2) {272} | PROGRAMMING | Codeforces Round #167 tutorial | 2300 | |
| 1943 | Greg and Friends | combinatorics dp graphs shortest paths | Statement | C | Codeforces Round 179 (Div. 1) {295} | PROGRAMMING | Codeforces Round #179 tutorial | 2500 | |
| 959 | The Red Button | combinatorics dfs and similar dsu graphs greedy | Statement | E | MemSQL start[c]up Round 1 {325} | PROGRAMMING | Editorial | 2700 | |
| 2760 | Iahub and Permutations | combinatorics math | Statement | E | Codeforces Round 198 (Div. 2) {340} | PROGRAMMING | Tutorial | 2200 | |
| 7065 | Unbearable Controversy of Being | brute force combinatorics dfs and similar graphs | Statement | D | Codeforces Round 277.5 (Div. 2) {489} | PROGRAMMING | Codeforces Round #277.5 (Div. 2) Editorial [A-D for now] | 1700 | |
| 3282 | New Year Santa Network | combinatorics dfs and similar graphs trees | Statement | D | Good Bye 2014 {500} | PROGRAMMING | Tutorial 2 | 1900 | |
| 2388 | Vitaly and Cycle | combinatorics dfs and similar graphs math | Statement | D | Codeforces Round 311 (Div. 2) {557} | PROGRAMMING | Codeforces Round #311 (Div.2) Editorial | 2300 | |
| 2113 | Pig and Palindromes | combinatorics dp | Statement | E | Codeforces Round 316 (Div. 2) {570} | PROGRAMMING | Codeforces Round #316 Editorial | 2600 | |
| 2016 | Square Root of Permutation | combinatorics constructive algorithms dfs and similar graphs math | Statement | E | Educational Codeforces Round 4 {612} | PROGRAMMING | 22299 | 2200 | |
| 5021 | Directed Roads | combinatorics dfs and similar graphs math | Statement | D | Codeforces Round 369 (Div. 2) {711} | PROGRAMMING | 46830 | 1900 | |
| 456 | Complete the Permutations | combinatorics fft graphs math | Statement | E | Codeforces Round 372 (Div. 1) {715} | PROGRAMMING | Codeforces Round #372 Editorial | 3400 | |
| 480 | Tree nesting | combinatorics graphs trees | Statement | F | Educational Codeforces Round 17 {762} | PROGRAMMING | Tutorial | 2900 | |
| 2900 | 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 | |
| 215 | Fake bullions | combinatorics dfs and similar dp graphs number theory | Statement | F | Codeforces Round 411 (Div. 1) {804} | PROGRAMMING | Codeforces Round #411 Editorial | 3400 | |
| 728 | An unavoidable detour for home | combinatorics dp graphs shortest paths | Statement | E | Codeforces Round 418 (Div. 2) {814} | PROGRAMMING | Codeforces Round #418 (Div. 2) Editorial | 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 | |
| 456 | Shake It! | combinatorics dp flows graphs | Statement | D | Codeforces Round 431 (Div. 1) {848} | PROGRAMMING | Codeforces Round #431 Editorial | 2900 | |
| 2120 | Desk Disorder | combinatorics dfs and similar dsu graphs trees | Statement | E | MemSQL Start[c]UP 3.0 - Round 1 {859} | PROGRAMMING | Tutorial | 2100 | |
| 517 | Cycles in product | combinatorics divide and conquer trees | Statement | D | Codeforces Round 493 (Div. 1) {997} | PROGRAMMING | 60357 | 2800 | |
| 1506 | 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 | |
| 5698 | 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 | |
| 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 |
| 3186 | Divisor Paths | combinatorics graphs greedy math number theory | Statement | E | Educational Codeforces Round 85 (Rated for Div. 2) {1334} | PROGRAMMING | Educational Codeforces Round 85 Editorial | ||
| 16058 | Cyclic Permutations | combinatorics graphs math | Statement | C | Codeforces Round 663 (Div. 2) {1391} | PROGRAMMING | 1250.0 | Codeforces Round #663 (Div. 2) Editorial | |
| 236 | 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 | ||
| 1342 | Clusterization Counting | combinatorics dp dsu fft graphs | Statement | G | Grakn Forces 2020 {1408} | PROGRAMMING | 3000.0 | Grakn Forces -- Editorial | |
| 6674 | 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 | ||
| 27511 | Ball in Berland | combinatorics dfs and similar graphs hashing math | Statement | C | Codeforces Round 697 (Div. 3) {1475} | PROGRAMMING | Codeforces Round #697 (Div. 3) Editorial | ||
| 1541 | 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 | |
| 2144 | Two Houses | brute force combinatorics graphs interactive probabilities sortings | Statement | E | CodeCraft-21 and Codeforces Round 711 (Div. 2) {1498} | PROGRAMMING | 2500.0 | CodeCraft-21 and Codeforces Round #711 (Div. 2) Editorial | |
| 13885 | 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 | |
| 2740 | Omkar and Forest | combinatorics graphs math shortest paths | Statement | E | Codeforces Round 724 (Div. 2) {1536} | PROGRAMMING | 2250.0 | Codeforces Round #724 — Editorial | 2300 |
| 769 | AquaMoon and Permutations | combinatorics constructive algorithms graph matchings graphs | Statement | C | Codeforces Round 732 (Div. 1) {1545} | PROGRAMMING | 1500.0 | Codeforces Round #732 Editorial | 2800 |
| 16978 | Running for Gold | combinatorics graphs greedy probabilities sortings | Statement | B | Codeforces Global Round 15 {1552} | PROGRAMMING | 500.0 | Editorial of Global Round 15 | |
| 3788 | Permutation Shift | brute force combinatorics constructive algorithms dfs and similar graphs math | Statement | E | Harbour.Space Scholarship Contest 2021-2022 (open for everyone, rated, Div. 1 + Div. 2) {1553} | PROGRAMMING | 1750.0 | Harbour.Space Scholarship Contest 2021-2022 (Div. 1 + Div. 2) Editorial | |
| 1423 | Sports Betting | bitmasks combinatorics dp graphs math probabilities | Statement | F | Deltix Round, Summer 2021 (open for everyone, rated, Div. 1 + Div. 2) {1556} | PROGRAMMING | 2500.0 | 94384 | 2500 |
| 747 | Occurrences | combinatorics dp dsu fft graphs | Statement | F | Educational Codeforces Round 114 (Rated for Div. 2) {1574} | PROGRAMMING | 95188 | ||
| 1563 | Dominoes | combinatorics fft graphs math | Statement | D | Codeforces Round 758 (Div.1 + Div. 2) {1608} | PROGRAMMING | 1500.0 | Editorial of Codeforces Round #758 (Div.1 + Div. 2) | |
| 2506 | Star MST | combinatorics dp math | Statement | E | Educational Codeforces Round 125 (Rated for Div. 2) {1657} | PROGRAMMING | 101161 | ||
| 1452 | 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 | ||
| 299 | Imitating the Key Tree | combinatorics dsu trees | Statement | I | COMPFEST 14 - Preliminary Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1725} | PROGRAMMING | Tutorial | ||
| 1016 | 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 | |
| 11228 | Playoff | combinatorics constructive algorithms dp graphs greedy | Statement | D | Educational Codeforces Round 140 (Rated for Div. 2) {1767} | PROGRAMMING | 110225 | ||
| 3828 | Game on Axis | combinatorics dsu graphs implementation | Statement | D | TypeDB Forces 2023 (Div. 1 + Div. 2, Rated, Prizes!) {1787} | PROGRAMMING | 2000.0 | TypeDB Forces 2023 (Div. 1 + Div. 2, Rated, Prizes!) Editorial | |
| 5522 | Counting Graphs | combinatorics divide and conquer dsu graphs greedy sortings | Statement | G | Codeforces Round 891 (Div. 3) {1857} | PROGRAMMING | 119134 | ||
| 834 | Swaps | combinatorics graphs | Statement | G | Pinely Round 2 (Div. 1 + Div. 2) {1863} | PROGRAMMING | 2750.0 | ||
| 1050 | 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 | |
| 282 | Cacti Symphony | combinatorics dfs and similar dp graphs | Statement | E | Codeforces Round 908 (Div. 1) {1893} | PROGRAMMING | 2750.0 | Codeforces Round 908 (Div. 1, Div, 2) Editorial | |
| 1103 | Count BFS Graph | combinatorics dp | Statement | J | 2023-2024 ICPC, Asia Jakarta Regional Contest (Online Mirror, Unrated, ICPC Rules, Teams Preferred) {1906} | PROGRAMMING | problem_analysis.pdf | ||
| 2413 | 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 | ||
| 1834 | 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 | ||
| 12151 | Chat Screenshots | combinatorics dfs and similar graphs implementation | Statement | F | Codeforces Round 925 (Div. 3) {1931} | PROGRAMMING | 125878 | ||
| 6519 | Non-academic Problem | combinatorics dfs and similar dsu graphs | Statement | F | Codeforces Round 954 (Div. 3) {1986} | PROGRAMMING | 130762 | ||
| 2904 | Cases | bitmasks brute force combinatorics dfs and similar dp graphs greedy strings | Statement | D | Codeforces Round 961 (Div. 2) {1995} | PROGRAMMING | 2250.0 | Video Tutorial | |
| 169 | Dora's Paint | brute force combinatorics constructive algorithms graphs | Statement | F | Codeforces Round 969 (Div. 1) {2006} | PROGRAMMING | 3000.0 | Tutorial | |
| 768 | 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 | |
| 717 | 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 | |
| 2690 | 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 | |
| 3870 | She knows... | combinatorics constructive algorithms graphs math | Statement | E | Codeforces Round 1014 (Div. 2) {2092} | PROGRAMMING | 2250.0 | Codeforces Round #1014 (Div. 2) Editorial | |
| 1947 | Baggage Claim | combinatorics dsu graphs math trees | Statement | B | Codeforces Round 1021 (Div. 1) {2097} | PROGRAMMING | 1000.0 | 142316 | |
| 3411 | Tree Colorings | combinatorics dp graphs math trees | Statement | E | Educational Codeforces Round 180 (Rated for Div. 2) {2112} | PROGRAMMING | Educational Codeforces Round 180 — Editorial | ||
| 6469 | 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 | |
| 894 | Sea, You & copriMe | brute force combinatorics constructive algorithms graphs greedy math number theory | Statement | H | Codeforces Round 1042 (Div. 3) {2131} | PROGRAMMING | Codeforces Round 1042 (Div. 3) Editorial | ||
| 263 | Distinct GCDs (Hard Version) | combinatorics constructive algorithms graphs graphs graphs math number theory number theory | Statement | F2 | Codeforces Round 1067 (Div. 2) {2158} | PROGRAMMING | 1000.0 | Codeforces Round 1067 (Div. 2) Editorial | |
| 1905 | Twin Polynomials | combinatorics graph matchings graphs math | Statement | C | Codeforces Round 1058 (Div. 1) {2159} | PROGRAMMING | 1500.0 | Codeforces Round 1058 Editorial | |
| 353 | SubMST | combinatorics graphs trees | Statement | F | Pinely Round 5 (Div. 1 + Div. 2) {2161} | PROGRAMMING | 3250.0 | ||
| 3719 | Interactive Graph (Simple Version) | combinatorics dfs and similar dp graphs interactive | Statement | C1 | Codeforces Round 1079 (Div. 1) {2196} | PROGRAMMING | 750.0 | Tutorial | |
| 2612 | Interactive Graph (Hard Version) | combinatorics dfs and similar dp graphs interactive | Statement | C2 | Codeforces Round 1079 (Div. 1) {2196} | PROGRAMMING | 750.0 | Tutorial | |
| 1546 | Deconstruction Tree | combinatorics data structures dp graphs trees | Statement | E | Spectral::Cup 2026 Round 2 (Codeforces Round 1100, Div. 1 + Div. 2) {2229} | PROGRAMMING | 2500.0 | Spectral::Cup 2026 Round 2 (Codeforces Round 1100, Div. 1 + Div. 2) Editorial |