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15902 Inversion Graph dsu graphs math Statement C Codeforces Round 771 (Div. 2) {1638} PROGRAMMING 1250.0 Codeforces Round #771 Editorial
2839 Anonymity Is Important binary search data structures dsu sortings Statement C Codeforces Round 773 (Div. 1) {1641} PROGRAMMING 1250.0 Codeforces Round #773 editorial
504 Air Reform data structures dfs and similar divide and conquer dsu graphs implementation trees Statement E Codeforces Round 775 (Div. 1, based on Moscow Open Olympiad in Informatics) {1648} PROGRAMMING 2500.0 Codeforces Round #775 Editorial
1964 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
1120 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
10979 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
3163 Preorder combinatorics divide and conquer dp dsu hashing trees Statement E Educational Codeforces Round 127 (Rated for Div. 2) {1671} PROGRAMMING 102181
12060 Replace With the Previous, Minimize dsu greedy strings Statement E Codeforces Round 787 (Div. 3) {1675} PROGRAMMING 102550
4075 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
896 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
2292 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
510 Permutation Weight (Easy Version) constructive algorithms dfs and similar dsu Statement D1 Codeforces Round 794 (Div. 1) {1685} PROGRAMMING 1500.0 103198 2800
1680 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
4134 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
1358 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)
2092 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)
1128 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
4983 Guess The String binary search brute force constructive algorithms dsu interactive Statement D Educational Codeforces Round 130 (Rated for Div. 2) {1697} PROGRAMMING 103835
1449 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
17733 Split Into Two Sets dfs and similar dsu graph matchings graphs Statement E Codeforces Round 805 (Div. 3) {1702} PROGRAMMING 104763
3692 Qpwoeirut and Vertices binary search data structures dsu trees Statement E Codeforces Round 809 (Div. 2) {1706} PROGRAMMING 2250.0 Codeforces Round #809 Editorial
1895 DFS Trees data structures dfs and similar dsu graphs greedy trees Statement C Codeforces Round 808 (Div. 1) {1707} PROGRAMMING 1250.0 104930
3929 XOR Tree data structures dfs and similar dsu greedy trees Statement E Educational Codeforces Round 132 (Rated for Div. 2) {1709} PROGRAMMING 105164
1969 Cross Swapping dsu greedy matrices Statement E Codeforces Round 812 (Div. 2) {1713} PROGRAMMING 2500.0 Codeforces Round #812 (Div. 2) Editorial 2400
295 Imitating the Key Tree combinatorics dsu trees Statement I COMPFEST 14 - Preliminary Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1725} PROGRAMMING Tutorial
777 Kingdom of Criticism data structures dsu Statement K COMPFEST 14 - Preliminary Online Mirror (Unrated, ICPC Rules, Teams Preferred) {1725} PROGRAMMING Tutorial
13393 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
3020 Prefixes and Suffixes constructive algorithms dsu strings Statement D Codeforces Round 823 (Div. 2) {1730} PROGRAMMING 2250.0 Codeforces Round #823 — editorial 2200
10907 Phase Shift dfs and similar dsu graphs greedy strings Statement C Codeforces Round 824 (Div. 2) {1735} PROGRAMMING 1250.0 Codeforces Round #824 — editorial
3741 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>
1373 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>
346 Dangerous Laser Power constructive algorithms dsu sortings Statement G Codeforces Round 831 (Div. 1 + Div. 2) {1740} PROGRAMMING 2750.0 Tutorial 3100
1008 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
1195 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
8960 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
4389 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
3852 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
1335 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
2326 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
9023 Boris and His Amazing Haircut constructive algorithms data structures dp dsu greedy Statement D Hello 2023 {1779} PROGRAMMING 1500.0
3812 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
1146 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
561 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
15228 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
15546 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
614 Gasoline prices data structures divide and conquer dsu trees Statement E Codeforces Round 857 (Div. 1) {1801} PROGRAMMING 2500.0 Codeforces Round #857 Editorial
1904 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)
8921 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)
1186 DSU Master combinatorics dp dsu math Statement D Codeforces Round 858 (Div. 2) {1806} PROGRAMMING 2000.0 Codeforces Round #858 (Div. 2) Editorial
3897 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!)
2157 Is It Flower? dfs and similar dsu graphs implementation Statement F Codeforces Round 863 (Div. 3) {1811} PROGRAMMING 114788
917 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
1680 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
4527 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
26464 The Lakes dfs and similar dsu graphs implementation Statement E Codeforces Round 871 (Div. 4) {1829} PROGRAMMING Codeforces Round 871 (Div. 4) Editorial 1100
6367 Ksyusha and Chinchilla dfs and similar dp dsu greedy implementation trees Statement G Codeforces Round 874 (Div. 3) {1833} PROGRAMMING 116636
18256 Round Dance dsu graphs shortest paths Statement E Codeforces Round 874 (Div. 3) {1833} PROGRAMMING 116636
280 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
2152 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
4257 Professor Higashikata brute force data structures dsu greedy implementation sortings Statement D Codeforces Round 882 (Div. 2) {1847} PROGRAMMING 2000.0 Tutorial
2175 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
4019 Vlad and the Mountains data structures dsu graphs implementation sortings trees two pointers Statement G Codeforces Round 888 (Div. 3) {1851} PROGRAMMING 118667
5451 Counting Graphs combinatorics divide and conquer dsu graphs greedy sortings Statement G Codeforces Round 891 (Div. 3) {1857} PROGRAMMING 119134
7978 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.
7520 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
9472 Mad City dfs and similar dsu graphs shortest paths Statement H Codeforces Round 898 (Div. 4) {1873} PROGRAMMING 120634
1048 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
4002 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)
5668 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
13138 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)
2386 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
1806 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
1192 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)
642 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)
5114 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
5362 Microcycle data structures dfs and similar dsu graphs greedy trees Statement F Codeforces Round 923 (Div. 3) {1927} PROGRAMMING 125597
600 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
2957 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
481 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)
11451 XOUR data structures dsu sortings Statement G Codeforces Round 944 (Div. 4) {1971} PROGRAMMING Codeforces Round 944 (Div. 4) Editorial 1400
1569 Large Graph data structures dsu graphs number theory Statement F Codeforces Round 953 (Div. 2) {1978} PROGRAMMING 2500.0 130527
1215 Turtle and Intersected Segments data structures dsu graphs greedy Statement E Codeforces Round 949 (Div. 2) {1981} PROGRAMMING 2500.0 Simplified Chinese Tutorial
7210 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
1901 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
6393 Non-academic Problem combinatorics dfs and similar dsu graphs Statement F Codeforces Round 954 (Div. 3) {1986} PROGRAMMING 130762
7351 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
4337 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
23371 Sakurako's Hobby dp dsu graphs math Statement D Codeforces Round 970 (Div. 3) {2008} PROGRAMMING Codeforces Round 970 (Div. 3) Editorial
237 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)
203 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)
2182 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)
7393 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
1919 Digital Village (Easy Version) brute force data structures dp dsu graphs greedy implementation math shortest paths trees Statement E1 Codeforces Round 977 (Div. 2, based on COMPFEST 16 - Final Round) {2021} PROGRAMMING 1750.0 Codeforces Round #977 (Div. 2, based on COMPFEST 16 — Final Round) Editorial
1198 Digital Village (Hard Version) data structures dp dsu graphs math trees Statement E2 Codeforces Round 977 (Div. 2, based on COMPFEST 16 - Final Round) {2021} PROGRAMMING 750.0 Codeforces Round #977 (Div. 2, based on COMPFEST 16 — Final Round) Editorial
755 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
704 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
3908 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
9644 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
14086 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
18146 Kousuke's Assignment dp dsu greedy math Statement D Codeforces Round 981 (Div. 3) {2033} PROGRAMMING 135520
263 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)
3799 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
1906 Another Exercise on Graphs (hard version) binary search brute force dsu graphs shortest paths sortings trees Statement E2 Hello 2025 {2057} PROGRAMMING 2000.0
12173 Graph Composition dfs and similar dsu graphs greedy Statement E Codeforces Round 998 (Div. 3) {2060} PROGRAMMING Codeforces Round 998 (Div. 3) Editorial
1520 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
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
2344 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
1458 Mycraft Sand Sort combinatorics data structures dsu Statement E Codeforces Round 1005 (Div. 2) {2064} PROGRAMMING 2250.0 Codeforces Round 1005 (Div. 2) Editorial
362 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
756 Graph Inclusion data structures divide and conquer dsu Statement F Educational Codeforces Round 174 (Rated for Div. 2) {2069} PROGRAMMING 139774
1171 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
16049 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
1890 Baggage Claim combinatorics dsu graphs math trees Statement B Codeforces Round 1021 (Div. 1) {2097} PROGRAMMING 1000.0 142316
523 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
4405 Goblin dp dsu greedy math Statement F Codeforces Round 1020 (Div. 3) {2106} PROGRAMMING Codeforces Round 1020 (Div. 3) Editorial
14572 Neo's Escape data structures dsu graphs greedy implementation Statement C Codeforces Round 1022 (Div. 2) {2108} PROGRAMMING 1500.0 Codeforces Round 1022 Editorial
5118 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
2482 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
2725 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
16563 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
3860 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
83 Merging Vertices in a Graph *special dfs and similar dsu graphs Statement H Kotlin Heroes: Episode 13 {2141} PROGRAMMING Kotlin Heroes 13 Editorial
628 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
3538 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
612 Sink data structures dsu dsu graphs graphs Statement E Codeforces Round 1067 (Div. 2) {2158} PROGRAMMING 2750.0 Codeforces Round 1067 (Div. 2) Editorial
2295 Rectangles data structures dsu implementation two pointers Statement B Codeforces Round 1058 (Div. 1) {2159} PROGRAMMING 1500.0 Codeforces Round 1058 Editorial
5337 Make Connected brute force dsu implementation Statement B Pinely Round 5 (Div. 1 + Div. 2) {2161} PROGRAMMING 1000.0
1566 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
7047 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
11437 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
1809 Conquer or of Forest combinatorics dfs and similar dsu trees Statement F Good Bye 2025 {2178} PROGRAMMING 2750.0
5680 Exquisite Array combinatorics data structures dsu Statement E Codeforces Round 1072 (Div. 3) {2184} PROGRAMMING Codeforces Round 1072 (Div. 3) Editorial
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
617 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
4055 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
1754 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
299 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