Problemset - Codeforces

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Problems

#	Name
1977C	Nikita and LCM brute force, data structures, dp, greedy, math, number theory, sortings	1900	x6785
1977B	Binary Colouring bitmasks, constructive algorithms, greedy, math	1100	x17684
1977A	Little Nikita math	800	x33153
1976F	Remove Bridges data structures, dfs and similar, dp, greedy, sortings, trees	2800	x592
1976E	Splittable Permutations combinatorics, data structures, dfs and similar, greedy, math, trees	2500	x1045
1976D	Invertible Bracket Sequences binary search, combinatorics, data structures, divide and conquer, implementation, two pointers	2000	x4635
1976C	Job Interview binary search, dp, greedy, implementation, two pointers	1600	x10424
1976B	Increase/Decrease/Copy greedy, implementation	1100	x22308
1976A	Verify Password implementation, sortings, strings	800	x28662
1975I	Mind Bloom dp	3500	x100
1975H	378QAQ and Core greedy, strings	3500	x116
1975G	Zimpha Fan Club fft, greedy, math, strings	3000	x235
1975F	Set bitmasks, brute force, combinatorics, dfs and similar, divide and conquer, dp, math	2600	x833
1975E	Chain Queries binary search, data structures, dfs and similar, implementation, trees	2100	x2329
1975D	Paint the Tree brute force, dfs and similar, dp, greedy, shortest paths, trees	1700	x6066
1975C	Chamo and Mocha's Array binary search, brute force, greedy	1200	x14621
1975B	378QAQ and Mocha's Array brute force, greedy, math, sortings	1000	x17904
1975A	Bazoka and Mocha's Array brute force, greedy, implementation, sortings	800	x18543
1974G	Money Buys Less Happiness Now data structures, greedy, sortings	2000	x4381
1974F	Cutting Game binary search, brute force, data structures, implementation, sortings, two pointers	1900	x3587
1974E	Money Buys Happiness dp	1800	x8077
1974D	Ingenuity-2 constructive algorithms, greedy, implementation	1400	x14863
1974C	Beautiful Triple Pairs combinatorics, data structures	1400	x15829
1974B	Symmetric Encoding implementation, sortings, strings	800	x30345
1974A	Phone Desktop greedy, math	800	x33293
1973F	Maximum GCD Sum Queries bitmasks, brute force, dp, implementation, number theory	3100	x231
1973E	Cat, Fox and Swaps graphs, math, sortings	2500	x807
1973D	Cat, Fox and Maximum Array Split brute force, interactive, math	2400	x1924
1973C	Cat, Fox and Double Maximum constructive algorithms, greedy, implementation, math, sortings	1700	x8402
1973B	Cat, Fox and the Lonely Array binary search, bitmasks, data structures, greedy, math, two pointers	1300	x14161
1973A	Chess For Three brute force, dp, implementation, math	900	x24617
1972B	Coin Games games	900	x21693
1972A	Contest Proposal brute force, greedy, two pointers	800	x23001
1971H	±1 2-sat, dfs and similar, graphs	2100	x1858
1971G	XOUR data structures, dsu, sortings	1700	x9315
1971F	Circle Perimeter binary search, brute force, dfs and similar, geometry, implementation, math	1600	x10058
1971E	Find the Car binary search, math, sortings	1500	x14357
1971D	Binary Cut dp, greedy, implementation, sortings, strings	1100	x25974
1971C	Clock and Strings implementation	900	x33177
1971B	Different String implementation, strings	800	x37086
1971A	My First Sorting Problem implementation, sortings	800	x45407
1970G3	Min-Fund Prison (Hard) bitmasks, dfs and similar, dp, graphs, trees	2400	x346
1970G2	Min-Fund Prison (Medium) brute force, dfs and similar, dp, graphs, trees	2200	x589
1970G1	Min-Fund Prison (Easy) dfs and similar, trees	1900	x1361
1970F3	Playing Quidditch (Hard) implementation	2300	x360
1970F2	Playing Quidditch (Medium) implementation	2300	x346
1970F1	Playing Quidditch (Easy) implementation	2300	x426
1970E3	Trails (Hard) dp, matrices	2200	x751
1970E2	Trails (Medium) dp, matrices	2000	x1313
1970E1	Trails (Easy) dp	1800	x2224
1970D3	Arithmancy (Hard) interactive	3100	x111
1970D2	Arithmancy (Medium) constructive algorithms, interactive, probabilities, strings	2600	x209
1970D1	Arithmancy (Easy) brute force, constructive algorithms, interactive, strings	2100	x650
1970C3	Game on Tree (Hard) dfs and similar, dp, games, trees	1900	x1591
1970C2	Game on Tree (Medium) dfs and similar, dp, games, trees	1700	x2774
1970C1	Game on Tree (Easy) games	1400	x3505
1970B3	Exact Neighbours (Hard) constructive algorithms	2300	x490
1970B2	Exact Neighbours (Medium) constructive algorithms	2100	x819
1970B1	Exact Neighbours (Easy) constructive algorithms	1900	x1159
1970A3	Balanced Unshuffle (Hard) constructive algorithms, trees	2400	x468
1970A2	Balanced Unshuffle (Medium) brute force, constructive algorithms, trees	2400	x448
1970A1	Balanced Shuffle (Easy) implementation, sortings	1000	x5004
1969F	Card Pairing dp, greedy, hashing, implementation	3000	x277
1969E	Unique Array binary search, data structures, divide and conquer, dp, greedy	2400	x1390
1969D	Shop Game data structures, greedy, math, sortings	1900	x4649
1969C	Minimizing the Sum dp, implementation	1700	x8818
1969B	Shifts and Sorting constructive algorithms, greedy	1000	x19164
1969A	Two Friends constructive algorithms, implementation, math	800	x19996
1968G2	Division + LCP (hard version) binary search, brute force, data structures, dp, hashing, math, string suffix structures, strings	2200	x1976
1968G1	Division + LCP (easy version) binary search, data structures, dp, hashing, string suffix structures, strings	1900	x4304
1968F	Equal XOR Segments binary search, data structures	1800	x5538
1968E	Cells Arrangement constructive algorithms	1600	x10480
1968D	Permutation Game brute force, dfs and similar, games, graphs, greedy, math	1300	x14997
1968C	Assembly via Remainders constructive algorithms, number theory	1000	x25143
1968B	Prefiquence greedy, two pointers	800	x28007
1968A	Maximize? brute force, math, number theory	800	x34718
1967F	Next and Prev brute force, data structures, implementation	3200	x70
1967E2	Again Counting Arrays (Hard Version) combinatorics, dp, math	3500	x103
1967E1	Again Counting Arrays (Easy Version) combinatorics, dp, fft, math	3100	x217
1967D	Long Way to be Non-decreasing binary search, dfs and similar, graphs, implementation, shortest paths, two pointers	2800	x678
1967C	Fenwick Tree bitmasks, brute force, combinatorics, data structures, dp, math, trees	2300	x1783
1967B2	Reverse Card (Hard Version) brute force, math, number theory	2200	x3953
1967B1	Reverse Card (Easy Version) brute force, math, number theory	1400	x13356
1967A	Permutation Counting binary search, greedy, implementation, math, sortings	1400	x12546
1966B	Rectangle Filling constructive algorithms, implementation	1100	x15036
1966A	Card Exchange constructive algorithms, games, greedy	800	x17927
1965F	Conference data structures, flows	3300	x179
1965E	Connected Cubes constructive algorithms, games	3100	x305
1965D	Missing Subarray Sum constructive algorithms	2900	x432
1965C	Folding Strip constructive algorithms, greedy, strings	2300	x1951
1965B	Missing Subsequence Sum bitmasks, constructive algorithms, greedy, number theory	1800	x6769
1965A	Everything Nim games, greedy, math, sortings	1400	x13808
1958J	Necromancer *special problem	3200	x32
1958I	Equal Trees *special problem, graphs, meet-in-the-middle	3100	x34
1958H	Composite Spells *special problem, dp	2600	x79
1958G	Observation Towers *special problem	2400	x111
1958F	Narrow Paths *special problem, combinatorics	2000	x193
1958E	Yet Another Permutation Constructive *special problem, constructive algorithms	1900	x257
1958D	Staircase *special problem	1600	x534
1958C	Firewood *special problem	1500	x730