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Name |
Tags |
Solutions |
Index |
Contest |
Type |
Points |
Tutorial |
Rating Level |
|---|---|---|---|---|---|---|---|---|---|
| 16001 | Inversion Graph | dsu graphs math | Statement | C | Codeforces Round 771 (Div. 2) {1638} | PROGRAMMING | 1250.0 | Codeforces Round #771 Editorial | |
| 2851 | Anonymity Is Important | binary search data structures dsu sortings | Statement | C | Codeforces Round 773 (Div. 1) {1641} | PROGRAMMING | 1250.0 | Codeforces Round #773 editorial | |
| 516 | 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 | |
| 1980 | AND-MEX Walk | bitmasks brute force data structures dfs and similar dsu graphs greedy | Statement | E | Codeforces Round 782 (Div. 2) {1659} | PROGRAMMING | 2250.0 | Codeforces Round #782 (Div. 2) Editorial | |
| 1124 | Narrow Components | data structures dfs and similar dsu trees | Statement | E | Educational Codeforces Round 126 (Rated for Div. 2) {1661} | PROGRAMMING | Educational Codeforces Round 126 Editorial | ||
| 11020 | Where is the Pizza? | data structures dfs and similar dsu graphs implementation math | Statement | C | Codeforces Round 788 (Div. 2) {1670} | PROGRAMMING | 1750.0 | Tutorial | 1400 |
| 3237 | Preorder | combinatorics divide and conquer dp dsu hashing trees | Statement | E | Educational Codeforces Round 127 (Rated for Div. 2) {1671} | PROGRAMMING | 102181 | ||
| 12137 | Replace With the Previous, Minimize | dsu greedy strings | Statement | E | Codeforces Round 787 (Div. 3) {1675} | PROGRAMMING | 102550 | ||
| 4099 | Tokitsukaze and Two Colorful Tapes | constructive algorithms dfs and similar dsu graphs greedy | Statement | C | Codeforces Round 789 (Div. 1) {1677} | PROGRAMMING | 1250.0 | Tutorial | |
| 908 | Lenient Vertex Cover | data structures dfs and similar divide and conquer dsu graphs | Statement | F | Educational Codeforces Round 128 (Rated for Div. 2) {1680} | PROGRAMMING | 102852 | ||
| 2339 | Unique Occurrences | data structures dfs and similar divide and conquer dp dsu trees | Statement | F | Educational Codeforces Round 129 (Rated for Div. 2) {1681} | PROGRAMMING | 103163 | 2300 | |
| 518 | Permutation Weight (Easy Version) | constructive algorithms dfs and similar dsu | Statement | D1 | Codeforces Round 794 (Div. 1) {1685} | PROGRAMMING | 1500.0 | 103198 | 2800 |
| 1693 | Sanae and Giant Robot | brute force constructive algorithms data structures dfs and similar dsu | Statement | C | Codeforces Round 796 (Div. 1) {1687} | PROGRAMMING | 1500.0 | Editorial of Codeforces Round 796 | |
| 4155 | Railway System | constructive algorithms dsu graphs greedy interactive sortings | Statement | B | Codeforces Round 796 (Div. 1) {1687} | PROGRAMMING | 750.0 | Editorial of Codeforces Round 796 | |
| 1368 | ANDfinity | bitmasks brute force constructive algorithms dfs and similar dsu graphs | Statement | E | Codeforces Round 798 (Div. 2) {1689} | PROGRAMMING | 2500.0 | Editorial for Codeforces Round #798 (Div. 2) | |
| 2105 | Number of Groups | data structures dfs and similar dsu graphs greedy sortings | Statement | E | CodeCraft-22 and Codeforces Round 795 (Div. 2) {1691} | PROGRAMMING | 2250.0 | Editorial for CodeCraft-22 and Codeforces Round #795 (Div. 2) | |
| 1144 | Tree Recovery | bitmasks brute force constructive algorithms dfs and similar dsu graphs trees | Statement | F | Codeforces Global Round 21 {1696} | PROGRAMMING | 2500.0 | Editorial of Codeforces Global Round 21 | |
| 5013 | Guess The String | binary search brute force constructive algorithms dsu interactive | Statement | D | Educational Codeforces Round 130 (Rated for Div. 2) {1697} | PROGRAMMING | 103835 | ||
| 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 | ||
| 18160 | Split Into Two Sets | dfs and similar dsu graph matchings graphs | Statement | E | Codeforces Round 805 (Div. 3) {1702} | PROGRAMMING | 104763 | ||
| 3783 | Qpwoeirut and Vertices | binary search data structures dsu trees | Statement | E | Codeforces Round 809 (Div. 2) {1706} | PROGRAMMING | 2250.0 | Codeforces Round #809 Editorial | |
| 1924 | DFS Trees | data structures dfs and similar dsu graphs greedy trees | Statement | C | Codeforces Round 808 (Div. 1) {1707} | PROGRAMMING | 1250.0 | 104930 | |
| 3998 | XOR Tree | data structures dfs and similar dsu greedy trees | Statement | E | Educational Codeforces Round 132 (Rated for Div. 2) {1709} | PROGRAMMING | 105164 | ||
| 1990 | Cross Swapping | dsu greedy matrices | Statement | E | Codeforces Round 812 (Div. 2) {1713} | PROGRAMMING | 2500.0 | Codeforces Round #812 (Div. 2) Editorial | 2400 |
| 299 | Imitating the Key Tree | combinatorics dsu trees | Statement | I | COMPFEST 14 - Preliminary Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1725} | PROGRAMMING | Tutorial | ||
| 791 | Kingdom of Criticism | data structures dsu | Statement | K | COMPFEST 14 - Preliminary Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1725} | PROGRAMMING | Tutorial | ||
| 13424 | Jatayu's Balanced Bracket Sequence | data structures dsu graphs | Statement | C | Codeforces Round 819 (Div. 1 + Div. 2) and Grimoire of Code Annual Contest 2022 {1726} | PROGRAMMING | 1500.0 | Codeforces Round #819 (Div. 1 + Div. 2) and Grimoire of Code Annual Contest 2022 Editorial | |
| 3034 | Prefixes and Suffixes | constructive algorithms dsu strings | Statement | D | Codeforces Round 823 (Div. 2) {1730} | PROGRAMMING | 2250.0 | Codeforces Round #823 — editorial | 2200 |
| 10969 | Phase Shift | dfs and similar dsu graphs greedy strings | Statement | C | Codeforces Round 824 (Div. 2) {1735} | PROGRAMMING | 1250.0 | Codeforces Round #824 — editorial | |
| 3763 | Permutation Addicts | constructive algorithms dfs and similar dsu graphs trees | Statement | D | Codeforces Global Round 22 {1738} | PROGRAMMING | 2000.0 | Editorial of Codeforces Global Round <strong>22</strong> | |
| 1390 | Connectivity Addicts | constructive algorithms dsu graphs greedy interactive shortest paths sortings trees | Statement | F | Codeforces Global Round 22 {1738} | PROGRAMMING | 2750.0 | Editorial of Codeforces Global Round <strong>22</strong> | |
| 359 | Dangerous Laser Power | constructive algorithms dsu sortings | Statement | G | Codeforces Round 831 (Div. 1 + Div. 2) {1740} | PROGRAMMING | 2750.0 | Tutorial | 3100 |
| 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 | |
| 1197 | Doremy's Experimental Tree | brute force constructive algorithms dfs and similar dsu sortings trees | Statement | F | Codeforces Global Round 24 {1764} | PROGRAMMING | 2250.0 | Codeforces Global Round 24 Editorial | |
| 9086 | Lucky Permutation | dfs and similar dsu graphs greedy | Statement | D | Codeforces Round 842 (Div. 2) {1768} | PROGRAMMING | 1750.0 | Codeforces Round #842 (Div. 2) Editorial | |
| 4408 | Koxia and Game | data structures dfs and similar dsu games graph matchings graphs implementation | Statement | D | Good Bye 2022: 2023 is NEAR {1770} | PROGRAMMING | 1500.0 | Good Bye 2022 -- Editorial | |
| 3887 | The Human Equation | data structures dp dsu greedy | Statement | E | Codeforces Round 843 (Div. 2) {1775} | PROGRAMMING | 2250.0 | Codeforces Round #843 (Div. 2) Editorial | |
| 1384 | Comfortably Numb | binary search bitmasks data structures divide and conquer dsu strings trees two pointers | Statement | F | Codeforces Round 845 (Div. 2) and ByteRace 2023 {1777} | PROGRAMMING | 2750.0 | Codeforces Round #845 (Div. 2) and ByteRace 2023 Editorial | |
| 2355 | Edge Reverse | binary search dfs and similar dsu graphs | Statement | E | Codeforces Round 845 (Div. 2) and ByteRace 2023 {1777} | PROGRAMMING | 2250.0 | Codeforces Round #845 (Div. 2) and ByteRace 2023 Editorial | |
| 9087 | Boris and His Amazing Haircut | constructive algorithms data structures dp dsu greedy | Statement | D | Hello 2023 {1779} | PROGRAMMING | 1500.0 | ||
| 3829 | 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 | |
| 1177 | XOR, Tree, and Queries | constructive algorithms dfs and similar dsu graphs trees | Statement | F | Codeforces Round 851 (Div. 2) {1788} | PROGRAMMING | 3000.0 | Codeforces Round #851 (Div. 2) Editorial | |
| 567 | Li Hua and Path | data structures dfs and similar divide and conquer dsu trees | Statement | F | Codeforces Round 864 (Div. 2) {1797} | PROGRAMMING | 3000.0 | Codeforces Round 864 (Div. 2) Editorial | |
| 15344 | Unforgivable Curse (hard version) | brute force constructive algorithms constructive algorithms dsu graphs greedy | Statement | E2 | Codeforces Round 855 (Div. 3) {1800} | PROGRAMMING | Codeforces Round 855 (Div. 3) Editorial | ||
| 15675 | Unforgivable Curse (easy version) | brute force constructive algorithms dsu graphs greedy | Statement | E1 | Codeforces Round 855 (Div. 3) {1800} | PROGRAMMING | Codeforces Round 855 (Div. 3) Editorial | ||
| 619 | Gasoline prices | data structures divide and conquer dsu trees | Statement | E | Codeforces Round 857 (Div. 1) {1801} | PROGRAMMING | 2500.0 | Codeforces Round #857 Editorial | |
| 1923 | 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) | |
| 9190 | A Wide, Wide Graph | dfs and similar dp dsu greedy trees | Statement | D | Codeforces Round 862 (Div. 2) {1805} | PROGRAMMING | 1750.0 | Editorial of Codeforces Round #862 (Div. 2) | |
| 1197 | DSU Master | combinatorics dp dsu math | Statement | D | Codeforces Round 858 (Div. 2) {1806} | PROGRAMMING | 2000.0 | Codeforces Round #858 (Div. 2) Editorial | |
| 3944 | 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!) | |
| 2184 | Is It Flower? | dfs and similar dsu graphs implementation | Statement | F | Codeforces Round 863 (Div. 3) {1811} | PROGRAMMING | 114788 | ||
| 946 | Communication Towers | brute force divide and conquer dsu | Statement | F | Educational Codeforces Round 146 (Rated for Div. 2) {1814} | PROGRAMMING | Educational Codeforces Round 146 Editorial | ||
| 1693 | LuoTianyi and XOR-Tree | data structures dfs and similar dp dsu greedy trees | Statement | C | Codeforces Round 872 (Div. 1) {1824} | PROGRAMMING | 1750.0 | CodeForces Round 872(Div. 1&2) Editorial | 2500 |
| 4556 | Range Sorting (Easy Version) | binary search dp dsu greedy trees two pointers | Statement | B1 | Codeforces Round 873 (Div. 1) {1827} | PROGRAMMING | 750.0 | Codeforces Round #873 (Div. 1 & 2) Editorial | 2000 |
| 27027 | The Lakes | dfs and similar dsu graphs implementation | Statement | E | Codeforces Round 871 (Div. 4) {1829} | PROGRAMMING | Codeforces Round 871 (Div. 4) Editorial | 1100 | |
| 6433 | Ksyusha and Chinchilla | dfs and similar dp dsu greedy implementation trees | Statement | G | Codeforces Round 874 (Div. 3) {1833} | PROGRAMMING | 116636 | ||
| 18799 | Round Dance | dsu graphs shortest paths | Statement | E | Codeforces Round 874 (Div. 3) {1833} | PROGRAMMING | 116636 | ||
| 296 | Multiple of Three Cycles | combinatorics dp dsu math | Statement | H | Codeforces Round 884 (Div. 1 + Div. 2) {1844} | PROGRAMMING | 4000.0 | Codeforces Round #884 (Div. 1 + Div. 2) Editorial | |
| 2168 | Great Grids | constructive algorithms dfs and similar dsu graphs math | Statement | E | Codeforces Round 884 (Div. 1 + Div. 2) {1844} | PROGRAMMING | 2000.0 | Codeforces Round #884 (Div. 1 + Div. 2) Editorial | |
| 4277 | Professor Higashikata | brute force data structures dsu greedy implementation sortings | Statement | D | Codeforces Round 882 (Div. 2) {1847} | PROGRAMMING | 2000.0 | Tutorial | |
| 2204 | Max to the Right of Min | binary search data structures divide and conquer dsu two pointers | Statement | E | Educational Codeforces Round 152 (Rated for Div. 2) {1849} | PROGRAMMING | 118752 | ||
| 4088 | Vlad and the Mountains | data structures dsu graphs implementation sortings trees two pointers | Statement | G | Codeforces Round 888 (Div. 3) {1851} | PROGRAMMING | 118667 | ||
| 5523 | Counting Graphs | combinatorics divide and conquer dsu graphs greedy sortings | Statement | G | Codeforces Round 891 (Div. 3) {1857} | PROGRAMMING | 119134 | ||
| 8028 | Andrey and Escape from Capygrad | binary search data structures dp dsu greedy sortings two pointers | Statement | D | Codeforces Round 892 (Div. 2) {1859} | PROGRAMMING | 1750.0 | Video solutions from Geothermal. | |
| 7579 | Selling a Menagerie | dfs and similar dsu graphs implementation math | Statement | F | Codeforces Round 895 (Div. 3) {1872} | PROGRAMMING | Codeforces Round 895 (Div. 3) Editorial | ||
| 9599 | Mad City | dfs and similar dsu graphs shortest paths | Statement | H | Codeforces Round 898 (Div. 4) {1873} | PROGRAMMING | 120634 | ||
| 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 | |
| 4054 | Unusual Entertainment | data structures dfs and similar dsu shortest paths sortings trees | Statement | G | Codeforces Round 909 (Div. 3) {1899} | PROGRAMMING | Разбор Codeforces Round 909 (Div. 3) | ||
| 5759 | Set To Max (Hard Version) | binary search constructive algorithms data structures dsu greedy implementation sortings two pointers | Statement | D2 | Codeforces Round 914 (Div. 2) {1904} | PROGRAMMING | 750.0 | Codeforces Round 914 (Div. 2) Editorial | |
| 13247 | Heavy Intervals | constructive algorithms data structures dsu greedy math sortings | Statement | C | Pinely Round 3 (Div. 1 + Div. 2) {1909} | PROGRAMMING | 1500.0 | Editorial of Pinely Round 3 (Div. 1 + Div. 2) | |
| 2414 | 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 | ||
| 1835 | 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 | ||
| 1200 | Smooth Sailing (Easy Version) | binary search data structures dfs and similar dsu graphs | Statement | F1 | Codeforces Round 919 (Div. 2) {1920} | PROGRAMMING | 2500.0 | Editorial for Codeforces Round #919 (Div. 2) | |
| 644 | 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) | |
| 5189 | Count Paths | data structures dfs and similar divide and conquer dp dsu trees | Statement | E | Educational Codeforces Round 162 (Rated for Div. 2) {1923} | PROGRAMMING | Educational Codeforces Round 162 Editorial | ||
| 5437 | Microcycle | data structures dfs and similar dsu graphs greedy trees | Statement | F | Codeforces Round 923 (Div. 3) {1927} | PROGRAMMING | 125597 | ||
| 611 | Andrey's Tree | binary search constructive algorithms dsu greedy implementation trees | Statement | F | Codeforces Round 932 (Div. 2) {1935} | PROGRAMMING | 3000.0 | Codeforces Round #932 (Div. 2) Editorial | |
| 105 | Parallel Universes | *special constructive algorithms dfs and similar dsu graphs | Statement | A | XVIII Open Olympiad in Informatics - Final Stage, Day 2 (Unrated, Online Mirror, IOI rules) {1940} | PROGRAMMING | |||
| 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 | |||
| 2989 | Chain Reaction | data structures dsu greedy implementation math number theory | Statement | E | Educational Codeforces Round 164 (Rated for Div. 2) {1954} | PROGRAMMING | Educational Codeforces Round 164 Editorial | ||
| 486 | Nene and the Passing Game | constructive algorithms data structures dsu graphs sortings | Statement | F | Codeforces Round 939 (Div. 2) {1956} | PROGRAMMING | 2500.0 | [Editorial] Codeforces Round 939 (Div. 2) | |
| 11581 | XOUR | data structures dsu sortings | Statement | G | Codeforces Round 944 (Div. 4) {1971} | PROGRAMMING | Codeforces Round 944 (Div. 4) Editorial | 1400 | |
| 1594 | Large Graph | data structures dsu graphs number theory | Statement | F | Codeforces Round 953 (Div. 2) {1978} | PROGRAMMING | 2500.0 | 130527 | |
| 1246 | Turtle and Intersected Segments | data structures dsu graphs greedy | Statement | E | Codeforces Round 949 (Div. 2) {1981} | PROGRAMMING | 2500.0 | Simplified Chinese Tutorial | |
| 7309 | Maximize the Largest Component (Easy Version) | brute force data structures dfs and similar dsu graphs implementation | Statement | H1 | Codeforces Round 952 (Div. 4) {1985} | PROGRAMMING | Codeforces Round 952 (Div. 4) Editorial | ||
| 1918 | Maximize the Largest Component (Hard Version) | data structures dfs and similar dsu implementation | Statement | H2 | Codeforces Round 952 (Div. 4) {1985} | PROGRAMMING | Codeforces Round 952 (Div. 4) Editorial | ||
| 6527 | Non-academic Problem | combinatorics dfs and similar dsu graphs | Statement | F | Codeforces Round 954 (Div. 3) {1986} | PROGRAMMING | 130762 | ||
| 7570 | Funny Game | constructive algorithms dsu graphs greedy math number theory | Statement | D | Codeforces Round 959 sponsored by NEAR (Div. 1 + Div. 2) {1994} | PROGRAMMING | 2000.0 | Video Tutorial | |
| 4381 | Iris and the Tree | brute force data structures dfs and similar dsu math trees | Statement | B | Codeforces Round 969 (Div. 1) {2006} | PROGRAMMING | 1250.0 | Tutorial | |
| 23557 | Sakurako's Hobby | dp dsu graphs math | Statement | D | Codeforces Round 970 (Div. 3) {2008} | PROGRAMMING | Codeforces Round 970 (Div. 3) Editorial | ||
| 241 | Complex Segments (Easy Version) | binary search data structures divide and conquer dsu greedy math sortings | Statement | E1 | Codeforces Round 975 (Div. 1) {2018} | PROGRAMMING | 2250.0 | Editorial of Codeforces Round 975 (Div. 1, Div. 2) | |
| 206 | Complex Segments (Hard Version) | binary search data structures divide and conquer dsu greedy math sortings | Statement | E2 | Codeforces Round 975 (Div. 1) {2018} | PROGRAMMING | 750.0 | Editorial of Codeforces Round 975 (Div. 1, Div. 2) | |
| 2206 | Max Plus Min Plus Size | data structures dp dsu greedy implementation matrices | Statement | D | Codeforces Round 975 (Div. 1) {2018} | PROGRAMMING | 1500.0 | Editorial of Codeforces Round 975 (Div. 1, Div. 2) | |
| 7466 | Connect the Dots | brute force dfs and similar dp dsu graphs math trees | Statement | D | Codeforces Round 976 (Div. 2) and Divide By Zero 9.0 {2020} | PROGRAMMING | 1500.0 | Tutorial for Codeforces Round 976 (Div. 2) and Divide By Zero 9.0 | |
| 1941 | 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 | |
| 1223 | 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 | |
| 769 | 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 | |
| 718 | 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 | |
| 3954 | 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 | |
| 9918 | Penchick and Desert Rabbit | data structures dfs and similar dp dsu greedy two pointers | Statement | D | Codeforces Round 987 (Div. 2) {2031} | PROGRAMMING | 2000.0 | Codeforces Round 987 (Div. 2) Editorial | |
| 14251 | Sakurako, Kosuke, and the Permutation | brute force data structures dfs and similar dsu fft greedy math | Statement | E | Codeforces Round 981 (Div. 3) {2033} | PROGRAMMING | 135520 | ||
| 18298 | Kousuke's Assignment | dp dsu greedy math | Statement | D | Codeforces Round 981 (Div. 3) {2033} | PROGRAMMING | 135520 | ||
| 270 | Bottle Arrangement | dsu greedy | Statement | J | 2024 ICPC Asia Taichung Regional Contest (Unrated, Online Mirror, ICPC Rules, Preferably Teams) {2041} | PROGRAMMING | Problem Analysis and Hints (PDF) | ||
| 3889 | Medium Demon Problem (hard version) | dfs and similar dp dsu graphs implementation trees | Statement | G2 | Codeforces Round 993 (Div. 4) {2044} | PROGRAMMING | Codeforces Round 993 (Div. 4) Editorial | ||
| 1939 | Another Exercise on Graphs (hard version) | binary search brute force dsu graphs shortest paths sortings trees | Statement | E2 | Hello 2025 {2057} | PROGRAMMING | 2000.0 | ||
| 12404 | Graph Composition | dfs and similar dsu graphs greedy | Statement | E | Codeforces Round 998 (Div. 3) {2060} | PROGRAMMING | Codeforces Round 998 (Div. 3) Editorial | ||
| 1560 | Counting Is Not Fun (Easy Version) | combinatorics data structures dfs and similar dsu implementation math | Statement | F1 | Codeforces Round 1000 (Div. 2) {2063} | PROGRAMMING | 1750.0 | Codeforces Round 1000 (Div. 2) — Editorial | |
| 935 | 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 | |
| 2399 | Triangle Tree | data structures dfs and similar dp dsu greedy trees | Statement | E | Codeforces Round 1000 (Div. 2) {2063} | PROGRAMMING | 2750.0 | Codeforces Round 1000 (Div. 2) — Editorial | |
| 1486 | Mycraft Sand Sort | combinatorics data structures dsu | Statement | E | Codeforces Round 1005 (Div. 2) {2064} | PROGRAMMING | 2250.0 | Codeforces Round 1005 (Div. 2) Editorial | |
| 373 | Porto Vs. Benfica | data structures dfs and similar dsu graphs shortest paths | Statement | E | European Championship 2025 - Online Mirror (Unrated, ICPC Rules, Teams Preferred) {2068} | PROGRAMMING | 140239 | ||
| 798 | Graph Inclusion | data structures divide and conquer dsu | Statement | F | Educational Codeforces Round 174 (Rated for Div. 2) {2069} | PROGRAMMING | 139774 | ||
| 1211 | MST in Modulo Graph | constructive algorithms dsu graphs greedy math number theory sortings | Statement | D | Codeforces Round 1010 (Div. 1, Unrated) {2081} | PROGRAMMING | 1750.0 | Codeforces Round 1010 (Div. 1, Div. 2, based on Zhili Cup 2025) Editorial | |
| 16260 | Disappearing Permutation | dfs and similar dsu graphs greedy implementation | Statement | C | Educational Codeforces Round 177 (Rated for Div. 2) {2086} | PROGRAMMING | Educational Codeforces Round 177 Editorial | ||
| 1947 | Baggage Claim | combinatorics dsu graphs math trees | Statement | B | Codeforces Round 1021 (Div. 1) {2097} | PROGRAMMING | 1000.0 | 142316 | |
| 541 | Modulo 3 | data structures divide and conquer dsu trees | Statement | G | Educational Codeforces Round 178 (Rated for Div. 2) {2104} | PROGRAMMING | Educational Codeforces Round 178 Editorial | ||
| 4463 | Goblin | dp dsu greedy math | Statement | F | Codeforces Round 1020 (Div. 3) {2106} | PROGRAMMING | Codeforces Round 1020 (Div. 3) Editorial | ||
| 14882 | Neo's Escape | data structures dsu graphs greedy implementation | Statement | C | Codeforces Round 1022 (Div. 2) {2108} | PROGRAMMING | 1500.0 | Codeforces Round 1022 Editorial | |
| 5201 | Omg Graph | brute force dsu graphs greedy shortest paths sortings | Statement | G | Codeforces Round 1029 (Div. 3) {2117} | PROGRAMMING | Codeforces Round 1029 (Div. 3) Editorial | ||
| 2519 | Red Light, Green Light (Hard version) | binary search dfs and similar dp dsu graphs implementation number theory | Statement | D2 | Codeforces Round 1030 (Div. 2) {2118} | PROGRAMMING | 1000.0 | Codeforces Round 1030 (Div. 2) Editorial | |
| 3066 | Ancient Tree | constructive algorithms data structures dfs and similar dsu greedy trees | Statement | E | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) {2127} | PROGRAMMING | 2500.0 | Atto Round 1 (Codeforces Round 1041, Div. 1 + Div. 2) Editorial | |
| 17136 | Double Perspective | constructive algorithms dp dsu greedy | Statement | A | Codeforces Round 1040 (Div. 1) {2129} | PROGRAMMING | 500.0 | Codeforces Round 1040 (Div. 1, Div. 2) Editorial | |
| 4315 | By the Assignment | bitmasks dfs and similar dsu graphs | Statement | C | Codeforces Round 1046 (Div. 1) {2135} | PROGRAMMING | 1750.0 | Codeforces Round 1046 (Div. 1, Div. 2) Editorial | |
| 85 | Merging Vertices in a Graph | *special dfs and similar dsu graphs | Statement | H | Kotlin Heroes: Episode 13 {2141} | PROGRAMMING | Kotlin Heroes 13 Editorial | ||
| 671 | 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 | |
| 3782 | Adjusting Drones | binary search data structures dsu greedy implementation sortings | Statement | E | Codeforces Round 1066 (Div. 1 + Div. 2) {2157} | PROGRAMMING | 2000.0 | Codeforces Round 1066 (Div. 1 + Div. 2) Editorial | |
| 642 | Sink | data structures dsu dsu graphs graphs | Statement | E | Codeforces Round 1067 (Div. 2) {2158} | PROGRAMMING | 2750.0 | Codeforces Round 1067 (Div. 2) Editorial | |
| 2561 | Rectangles | data structures dsu implementation two pointers | Statement | B | Codeforces Round 1058 (Div. 1) {2159} | PROGRAMMING | 1500.0 | Codeforces Round 1058 Editorial | |
| 5437 | Make Connected | brute force dsu implementation | Statement | B | Pinely Round 5 (Div. 1 + Div. 2) {2161} | PROGRAMMING | 1000.0 | ||
| 1906 | Journey | dfs and similar dsu graphs greedy | Statement | E | Codeforces Global Round 30 (Div. 1 + Div. 2) {2164} | PROGRAMMING | 2250.0 | Codeforces Global Round 30 Editorial | |
| 7307 | Rae Taylor and Trees (hard version) | binary search constructive algorithms data structures dp dsu implementation trees | Statement | F | Codeforces Round 1065 (Div. 3) {2171} | PROGRAMMING | Codeforces Round 1065 (Div. 3) Editorial | ||
| 11853 | Rae Taylor and Trees (easy version) | binary search data structures dp dsu greedy implementation trees | Statement | D | Codeforces Round 1065 (Div. 3) {2171} | PROGRAMMING | Codeforces Round 1065 (Div. 3) Editorial | ||
| 1851 | Conquer or of Forest | combinatorics dfs and similar dsu trees | Statement | F | Good Bye 2025 {2178} | PROGRAMMING | 2750.0 | ||
| 5909 | Exquisite Array | combinatorics data structures dsu | Statement | E | Codeforces Round 1072 (Div. 3) {2184} | PROGRAMMING | Codeforces Round 1072 (Div. 3) Editorial | ||
| 978 | 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 | |
| 679 | Simons and Reconstructing His Roads | constructive algorithms data structures dsu graphs meet-in-the-middle | Statement | F | Codeforces Round 1083 (Div. 2) {2205} | PROGRAMMING | 2750.0 | Tutorial | |
| 4470 | Tree Orientation (Easy Version) | constructive algorithms dfs and similar dsu graphs greedy trees | Statement | D1 | Codeforces Round 1086 (Div. 2) {2208} | PROGRAMMING | 1250.0 | Tutorial | |
| 1949 | 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 | |
| 344 | Binary Strings are Simple? | constructive algorithms dsu interactive number theory | Statement | E | Codeforces Round 1089 (Div. 2) {2210} | PROGRAMMING | 2750.0 | Codeforces Round 1089 (Div. 2) Editorial | |
| 666 | Building Tree | divide and conquer dsu graphs implementation | Statement | F | Spectral::Cup 2026 Round 1 (Codeforces Round 1094, Div. 1 + Div. 2) {2222} | PROGRAMMING | 3000.0 | Spectral::Cup 2026 Round 1 (Codeforces Round 1094, Div. 1 + Div. 2) Editorial |