Problemset - Codeforces

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Codeforces Global Round 28
23:10:44
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Problems

#	Name
1921F	Sum of Progression brute force, data structures, dp, implementation, math	1900	x3980
1920E	Counting Binary Strings combinatorics, dp, math	2100	x2792
1920D	Array Repetition binary search, brute force, dsu, implementation, math	1900	x5711
1919H	Tree Diameter interactive, trees	2000	x145
1919D	01 Tree constructive algorithms, data structures, dsu, greedy, sortings, trees	2100	x3942
1918D	Blocking Elements binary search, data structures, dp, implementation, two pointers	1900	x4931
1914G1	Light Bulbs (Easy Version) brute force, combinatorics, dfs and similar, dp, dsu, graphs, math, trees	2100	x1947
1914F	Programming Competition dfs and similar, dp, graph matchings, greedy, trees	1900	x4224
1913D	Array Collapse data structures, divide and conquer, dp, trees	2100	x3265
1912D	Divisibility Test math	1900	x1586
1912B	Blueprint for Seating combinatorics, divide and conquer, math	2100	x1150
1912A	Accumulator Apex data structures, implementation, sortings	1900	x2226
1910F	Build Railway Stations *special problem, greedy, trees	2000	x181
1910E	Maximum Sum Subarrays *special problem, dp	2100	x206
1909I	Short Permutation Problem combinatorics, dp, fft, math	1900	x121
1909D	Split Plus K greedy, math, number theory	1900	x4536
1906J	Count BFS Graph combinatorics, dp	2100	x845
1906F	Maximize The Value data structures, sortings	2100	x1240
1906E	Merge Not Sort constructive algorithms, dp	1900	x1659
1905D	Cyclic MEX data structures, implementation, math, two pointers	2000	x3958
1903E	Geo Game greedy, interactive, math	2000	x2088
1902E	Collapsing Strings data structures, strings, trees	1900	x4438
1902D	Robot Queries binary search, data structures, dp, implementation	1900	x4244
1900E	Transitive Graph dfs and similar, dp, dsu, graphs, implementation	2100	x2142
1900D	Small GCD bitmasks, brute force, dp, math, number theory	2000	x4366
1899G	Unusual Entertainment data structures, dfs and similar, dsu, shortest paths, sortings, trees, two pointers	1900	x3330
1898D	Absolute Beauty greedy, math	1900	x5384
1896E	Permutation Sorting data structures, sortings	2100	x2270
1895D	XOR Construction bitmasks, constructive algorithms, data structures, math, string suffix structures, trees	1900	x6179
1893C	Freedom of Choice brute force, greedy, implementation	2000	x2768
1891F	A Growing Tree data structures, dfs and similar, trees	2000	x3916
1891D	Suspicious logarithms binary search, brute force, math	1900	x4035
1889C1	Doremy's Drying Plan (Easy Version) brute force, data structures, dp, greedy, sortings	2000	x3368
1887B	Time Travel binary search, graphs, shortest paths	1900	x3108
1886D	Monocarp and the Set combinatorics, data structures, math	2100	x3656
1884D	Counting Rhyme dp, math, number theory	2100	x3325
1883G2	Dances (Hard Version) binary search, greedy, sortings, two pointers	1900	x5545
1882D	Tree XOR bitmasks, dfs and similar, dp, greedy, trees	1900	x5636
1881G	Anya and the Mysterious String binary search, data structures	2000	x2447
1878F	Vasilije Loves Number Theory brute force, math, number theory	1900	x4203
1876C	Autosynthesis constructive algorithms, dfs and similar, graphs, greedy, sortings	2100	x2356
1872G	Replace With Product brute force, greedy, math	2000	x4382
1868B2	Candy Party (Hard Version) bitmasks, constructive algorithms, dp, greedy, implementation, math	2100	x2452
1867E1	Salyg1n and Array (simple version) constructive algorithms, interactive, math	2000	x3831
1866H	Happy Sets combinatorics	2100	x1684
1866G	Grouped Carriages binary search, data structures, dp, flows, greedy	2100	x1760
1866C	Completely Searching for Inversions dfs and similar, dp, graphs	1900	x3088
1864E	Guess Game bitmasks, data structures, games, math, probabilities, sortings, strings, trees	2100	x2695
1863E	Speedrun brute force, dfs and similar, dp, graphs, greedy, math, sortings, two pointers	2100	x2814
1862G	The Great Equalizer binary search, data structures, math, sortings	2000	x2940
1857G	Counting Graphs combinatorics, divide and conquer, dsu, graphs, greedy, sortings, trees	2000	x4575
1856D	More Wrong divide and conquer, interactive	2100	x3314
1854A2	Dual (Hard Version) constructive algorithms, math	1900	x7105
1851G	Vlad and the Mountains binary search, data structures, dsu, graphs, implementation, sortings, trees, two pointers	2000	x3331
1847D	Professor Higashikata data structures, dsu, greedy, implementation, strings	1900	x3859
1846G	Rudolf and CodeVid-23 bitmasks, dp, graphs, greedy, shortest paths	1900	x4519
1842D	Tenzing and His Animal Friends constructive algorithms, graphs, greedy	1900	x4156
1841D	Pairs of Segments data structures, greedy, sortings, two pointers	2000	x4516
1839D	Ball Sorting data structures, dp, sortings	2100	x2384
1838D	Bracket Walk data structures, greedy, strings	2100	x3324
1834D	Survey in Class brute force, data structures, greedy, implementation, sortings	1900	x4782
1832D1	Red-Blue Operations (Easy Version) binary search, greedy, implementation, math	2100	x3000
1830B	The BOSS Can Count Pairs brute force, math	2000	x5011
1827B1	Range Sorting (Easy Version) binary search, dp, dsu, greedy, trees, two pointers	2000	x3966
1823D	Unique Palindromes constructive algorithms, math, strings	1900	x3923
1821E	Rearrange Brackets brute force, dp, greedy, sortings, strings	2100	x2415
1821D	Black Cells binary search, brute force, greedy, math	1900	x5059
1819B	The Butcher geometry, greedy, implementation, sortings, two pointers	1900	x3658
1817B	Fish Graph brute force, constructive algorithms, dfs and similar, graphs	1900	x4229
1815B	Sum Graph brute force, constructive algorithms, graphs, implementation, interactive, shortest paths, trees	2000	x3098
1811G1	Vlad and the Nice Paths (easy version) combinatorics, dp, math	2100	x2122
1811F	Is It Flower? dfs and similar, graphs, implementation	2100	x1879
1810E	Monsters brute force, data structures, dfs and similar, dsu, graphs, greedy	2100	x3283
1808D	Petya, Petya, Petr, and Palindromes binary search, brute force, data structures, two pointers	2100	x2399
1808C	Unlucky Numbers brute force, dp, greedy, implementation	1900	x3883
1804D	Accommodation brute force, dp, greedy, implementation	2000	x4714
1801D	The way home binary search, data structures, dp, graphs, greedy, shortest paths, sortings	2100	x2306
1801C	Music Festival binary search, data structures, dp, greedy, sortings	1900	x3540
1800F	Dasha and Nightmares bitmasks, hashing, meet-in-the-middle, strings	1900	x3993
1799D2	Hot Start Up (hard version) data structures, dp	2100	x2572
1799D1	Hot Start Up (easy version) dp	1900	x4645
1797D	Li Hua and Tree brute force, data structures, dfs and similar, dp, implementation, trees	1900	x4054
1796D	Maximum Subarray data structures, dp, greedy, two pointers	2000	x4463
1794D	Counting Factorizations combinatorics, divide and conquer, dp, math, number theory	1900	x3652
1791G2	Teleporters (Hard Version) binary search, greedy, sortings	1900	x4888
1790F	Timofey and Black-White Tree brute force, dfs and similar, divide and conquer, graphs, greedy, math, shortest paths, trees	2100	x3406
1788D	Moving Dots binary search, brute force, combinatorics, math, two pointers	2000	x3995
1787E	The Harmonization of XOR bitmasks, constructive algorithms, greedy, math	2100	x2383
1787D	Game on Axis combinatorics, dfs and similar, dsu, graphs, implementation	1900	x3446
1784B	Letter Exchange constructive algorithms	1900	x3373
1783D	Different Arrays brute force, dp, implementation	2000	x4541
1778D	Flexible String Revisit combinatorics, dp, math, probabilities	2100	x2875
1777D	Score of a Tree bitmasks, combinatorics, dfs and similar, dp, math, probabilities, trees	1900	x3586
1776G	Another Wine Tasting Event combinatorics, constructive algorithms, math, strings	2100	x2100
1775E	The Human Equation greedy, implementation	2100	x3336
1774E	Two Chess Pieces dfs and similar, dp, greedy, trees	1900	x3552
1773K	King's Puzzle constructive algorithms	1900	x1485
1773A	Amazing Trick constructive algorithms, graph matchings, math, probabilities	1900	x1617
1772F	Copy of a Copy of a Copy constructive algorithms, dfs and similar, graphs, implementation, sortings	2000	x2422
1771D	Hossam and (sub-)palindromic tree brute force, data structures, dfs and similar, dp, strings, trees	2100	x2829