Problemset - Codeforces

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Codeforces Global Round 28
23:30:16
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Problems

#	Name
2052J	Judicious Watching binary search, greedy, sortings	2000	x426
2052E	Expression Correction brute force, expression parsing, strings	1900	x549
2052D	DAG Serialization brute force, graphs	2100	x370
2050G	Tree Destruction dfs and similar, dp, trees	1900	x2770
2046C	Adventurers binary search, data structures, greedy, sortings, ternary search, two pointers	2100	x1397
2045I	Microwavable Subsequence data structures	2100	x583
2045B	ICPC Square math, number theory	2000	x741
2042D	Recommendations data structures, implementation, sortings, two pointers	1900	x2894
2041M	Selection Sort binary search, data structures, greedy, two pointers	2000	x741
2041C	Cube bitmasks, dfs and similar, dp	2000	x1063
2040E	Control of Randomness combinatorics, dfs and similar, dp, graphs, greedy, math, probabilities, trees	2100	x1467
2040D	Non Prime Tree brute force, constructive algorithms, dfs and similar, greedy, number theory, trees, two pointers	1900	x3461
2038K	Grid Walk brute force, dp, greedy, math, number theory	2100	x1171
2038G	Guess One Character constructive algorithms, implementation, interactive	1900	x2021
2038B	Make It Equal binary search, brute force, greedy, math	2100	x1306
2037G	Natlan Exploring bitmasks, combinatorics, data structures, dp, math, number theory	2000	x2381
2037F	Ardent Flames binary search, data structures, math, sortings, two pointers	2100	x1941
2036F	XORificator 3000 bitmasks, dp, number theory, two pointers	1900	x3593
2031E	Penchick and Chloe's Trees data structures, dfs and similar, dp, greedy, implementation, math, sortings, trees	2100	x1972
2029E	Common Generator brute force, constructive algorithms, math, number theory	2100	x2591
2029D	Cool Graph constructive algorithms, data structures, dfs and similar, dsu, graphs, greedy, trees	1900	x2847
2028D	Alice's Adventures in Cards constructive algorithms, data structures, dp, graphs, greedy, implementation, ternary search	2000	x2640
2026D	Sums of Segments binary search, data structures, dp, implementation, math	1900	x4234
2022D1	Asesino (Easy Version) binary search, brute force, constructive algorithms, implementation, interactive	1900	x2955
2021C2	Adjust The Presentation (Hard Version) constructive algorithms, data structures, greedy, implementation, sortings	1900	x3658
2020E	Expected Power bitmasks, dp, math, probabilities	2000	x3078
2018B	Speedbreaker binary search, data structures, dp, greedy, implementation, two pointers	1900	x4077
2014H	Robin Hood Archery data structures, divide and conquer, greedy, hashing	1900	x3629
2014F	Sheriff's Defense dfs and similar, dp, greedy, trees	2000	x3681
2013D	Minimize the Difference binary search, greedy	1900	x6159
2009G1	Yunli's Subarray Queries (easy version) binary search, data structures, two pointers	1900	x3908
2008H	Sakurako's Test binary search, brute force, greedy, math, number theory	2100	x2954
2005E1	Subtangle Game (Easy Version) dp, games, greedy, implementation	2100	x2774
2004E	Not a Nim Problem brute force, games, math, number theory	2100	x4128
2003D2	Turtle and a MEX Problem (Hard Version) dfs and similar, dp, graphs, greedy, implementation, math	2100	x4051
2002D1	DFS Checker (Easy Version) brute force, data structures, dfs and similar, graphs, hashing, trees	1900	x4395
2001D	Longest Max Min Subsequence brute force, constructive algorithms, data structures, greedy, implementation	1900	x5115
2000G	Call During the Journey binary search, brute force, graphs, greedy, shortest paths	2100	x2399
2000F	Color Rows and Columns dp, greedy, implementation, math	1900	x5482
1998D	Determine Winning Islands in Race data structures, dp, graphs, greedy, shortest paths	2100	x3387
1998C	Perform Operations to Maximize Score binary search, brute force, constructive algorithms, greedy, implementation	1900	x6228
1996F	Bomb binary search, greedy, math	1900	x4883
1994E	Wooden Game bitmasks, greedy, math, trees	2000	x4591
1994D	Funny Game constructive algorithms, dsu, graphs, greedy, math, number theory, trees	1900	x5864
1992G	Ultra-Meow combinatorics, dp, math	2000	x3194
1992F	Valuable Cards brute force, dp, greedy, number theory, two pointers	1900	x5842
1991E	Coloring Game constructive algorithms, dfs and similar, games, graphs, greedy, interactive	1900	x4290
1991D	Prime XOR Coloring bitmasks, constructive algorithms, graphs, greedy, math, number theory	1900	x6766
1989D	Smithing Skill brute force, data structures, dp, greedy, math, sortings, two pointers	1900	x6066
1988D	The Omnipotent Monster Killer brute force, dfs and similar, dp, trees	2000	x5013
1987E	Wonderful Tree! brute force, data structures, dfs and similar, dsu, greedy, trees	2000	x3453
1986F	Non-academic Problem dfs and similar, graphs, trees	1900	x4685
1984D	''a'' String Problem brute force, hashing, implementation, math, string suffix structures, strings	2000	x3336
1980F1	Field Division (easy version) data structures, math, sortings	1900	x3811
1978E	Computing Machine brute force, data structures, dp, greedy, implementation	2000	x3887
1977C	Nikita and LCM brute force, data structures, dp, greedy, math, number theory, sortings	1900	x6851
1976D	Invertible Bracket Sequences binary search, combinatorics, data structures, divide and conquer, implementation, two pointers	2000	x4694
1975E	Chain Queries binary search, data structures, dfs and similar, implementation, trees	2100	x2366
1974G	Money Buys Less Happiness Now data structures, greedy, sortings	2000	x4451
1974F	Cutting Game binary search, brute force, data structures, implementation, sortings, two pointers	1900	x3643
1971H	±1 2-sat, dfs and similar, graphs	2100	x1904
1970G1	Min-Fund Prison (Easy) dfs and similar, trees	1900	x1396
1970E2	Trails (Medium) dp, matrices	2000	x1354
1970D1	Arithmancy (Easy) brute force, constructive algorithms, interactive, strings	2100	x673
1970C3	Game on Tree (Hard) dfs and similar, dp, games, trees	1900	x1646
1970B2	Exact Neighbours (Medium) constructive algorithms	2100	x845
1970B1	Exact Neighbours (Easy) constructive algorithms	1900	x1190
1969D	Shop Game data structures, greedy, math, sortings	1900	x4720
1968G1	Division + LCP (easy version) binary search, data structures, dp, hashing, string suffix structures, strings	1900	x4360
1958F	Narrow Paths *special problem, combinatorics	2000	x207
1958E	Yet Another Permutation Constructive *special problem, constructive algorithms	1900	x275
1957D	A BIT of an Inequality bitmasks, brute force, dp, math	1900	x4599
1956D	Nene and the Mex Operator bitmasks, brute force, constructive algorithms, divide and conquer, dp, greedy, implementation, math	2000	x3996
1955G	GCD on a grid brute force, dfs and similar, dp, implementation, math, number theory	1900	x4652
1951E	No Palindromes brute force, constructive algorithms, divide and conquer, greedy, hashing, implementation, math, strings	2000	x3696
1951D	Buying Jewels constructive algorithms, greedy, math	2000	x5495
1950G	Shuffling Songs bitmasks, dfs and similar, dp, graphs, hashing, implementation, strings	1900	x4528
1949C	Annual Ants' Gathering dfs and similar, dp, greedy, trees	1900	x1831
1948E	Clique Partition brute force, constructive algorithms, graphs, greedy, implementation	2100	x3047
1946D	Birthday Gift bitmasks, brute force, constructive algorithms, greedy, implementation	1900	x4809
1945F	Kirill and Mushrooms data structures, sortings	1900	x4318
1943B	Non-Palindromic Substring hashing, implementation, math, strings	2000	x3930
1942D	Learning to Paint binary search, data structures, dfs and similar, dp, greedy, implementation, sortings	2100	x2852
1941G	Rudolf and Subway constructive algorithms, dfs and similar, graphs, shortest paths	2000	x3647
1938J	There and Back Again	2100	x1321
1938C	Bit Counting Sequence	1900	x1505
1936B	Pinball binary search, data structures, implementation, math, two pointers	2000	x3017
1934D1	XOR Break --- Solo Version bitmasks, constructive algorithms, greedy	2100	x3592
1933F	Turtle Mission: Robot and the Earthquake dfs and similar, dp, graphs, shortest paths	2100	x2539
1932F	Feed Cats data structures, dp, sortings	1900	x4277
1931G	One-Dimensional Puzzle combinatorics, math, number theory	2000	x2918
1930D2	Sum over all Substrings (Hard Version) bitmasks, divide and conquer, dp, dsu, greedy, implementation, strings	2100	x2689
1929D	Sasha and a Walk in the City combinatorics, dp, math, trees	1900	x4913
1928D	Lonely Mountain Dungeons brute force, data structures, greedy, math, ternary search	1900	x4392
1927F	Microcycle data structures, dfs and similar, dsu, graphs, greedy, implementation, sortings, trees	1900	x4513
1926G	Vlad and Trouble at MIT dfs and similar, dp, flows, graphs, greedy, implementation, trees	1900	x3703
1925D	Good Trip combinatorics, dp, math, probabilities	1900	x3740
1924B	Space Harbour data structures, implementation, math, sortings	2100	x2642
1923E	Count Paths data structures, dfs and similar, dp, dsu, graphs, trees	2000	x4026
1922D	Berserk Monsters brute force, data structures, dsu, implementation, math	1900	x5821

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