Problemset - Codeforces

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Ethflow Round 1 (Codeforces Round, Div. 1 + Div. 2)
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Problems

#	Name
1407C	Chocolate Bunny constructive algorithms, interactive, math, two pointers	1600	x12406
1407B	Big Vova brute force, greedy, math, number theory	1300	x17200
1407A	Ahahahahahahahaha constructive algorithms, math	1100	x20604
1406E	Deleting Numbers interactive, math, number theory	2600	x1739
1406D	Three Sequences constructive algorithms, data structures, greedy, math	2200	x3559
1406C	Link Cut Centroids constructive algorithms, dfs and similar, graphs, trees	1700	x10484
1406B	Maximum Product brute force, dp, greedy, implementation, sortings	1200	x22964
1406A	Subset Mex greedy, implementation, math	900	x21744
1405B	Array Cancellation constructive algorithms, implementation	1000	x21862
1405A	Permutation Forgery constructive algorithms	800	x21541
1404E	Bricks flows, graph matchings, graphs	2800	x1304
1404D	Game of Pairs constructive algorithms, dfs and similar, interactive, math, number theory	2800	x1134
1404C	Fixed Point Removal binary search, constructive algorithms, data structures, greedy, two pointers	2300	x2729
1404B	Tree Tag dfs and similar, dp, games, trees	1900	x7558
1404A	Balanced Bitstring implementation, strings	1500	x15929
1403C	Chess Rush *special problem, combinatorics, dp, implementation, math	3200	x54
1403B	Spring cleaning *special problem, data structures, dfs and similar, graphs, trees	2300	x373
1403A	The Potion of Great Power *special problem, 2-sat, binary search, data structures, graphs, interactive, sortings, two pointers	2400	x295
1402C	Star Trek *special problem, combinatorics, dfs and similar, dp, games, graphs, matrices, trees	2600	x207
1402B	Roads *special problem, geometry, sortings	2900	x116
1402A	Fancy Fence *special problem, data structures, dsu, implementation, math, sortings	1800	x1216
1401F	Reverse and Swap binary search, bitmasks, data structures	2400	x1788
1401E	Divide Square data structures, geometry, implementation, sortings	2400	x2474
1401D	Maximum Distributed Tree dfs and similar, dp, greedy, implementation, math, number theory, sortings, trees	1800	x9441
1401C	Mere Array constructive algorithms, math, number theory, sortings	1300	x24682
1401B	Ternary Sequence constructive algorithms, greedy, math	1100	x21235
1401A	Distance and Axis constructive algorithms, math	900	x27714
1400G	Mercenaries bitmasks, brute force, combinatorics, dp, dsu, math, two pointers	2600	x1013
1400F	x-prime Substrings brute force, dfs and similar, dp, string suffix structures, strings	2800	x924
1400E	Clear the Multiset data structures, divide and conquer, dp, greedy	2200	x5628
1400D	Zigzags brute force, combinatorics, data structures, math, two pointers	1900	x10517
1400C	Binary String Reconstruction 2-sat, brute force, constructive algorithms, greedy	1500	x17561
1400B	RPG Protagonist brute force, greedy, math	1700	x11293
1400A	String Similarity constructive algorithms, strings	800	x27228
1399F	Yet Another Segments Subset data structures, dp, graphs, sortings	2300	x1666
1399E2	Weights Division (hard version) binary search, dfs and similar, greedy, sortings, trees, two pointers	2200	x2309
1399E1	Weights Division (easy version) data structures, dfs and similar, greedy, trees	2000	x5934
1399D	Binary String To Subsequences constructive algorithms, data structures, greedy, implementation	1500	x18545
1399C	Boats Competition brute force, greedy, two pointers	1200	x29706
1399B	Gifts Fixing greedy	800	x44167
1399A	Remove Smallest greedy, sortings	800	x68967
1398G	Running Competition bitmasks, fft, math, number theory	2600	x1133
1398F	Controversial Rounds binary search, data structures, dp, greedy, two pointers	2500	x1298
1398E	Two Types of Spells binary search, data structures, greedy, implementation, math, sortings	2200	x2450
1398D	Colored Rectangles dp, greedy, sortings	1800	x11682
1398C	Good Subarrays data structures, dp, math	1600	x27963
1398B	Substring Removal Game games, greedy, sortings	800	x24847
1398A	Bad Triangle geometry, math	800	x27826
1397B	Power Sequence brute force, math, number theory, sortings	1500	x14891
1397A	Juggling Letters greedy, strings	800	x28848
1396E	Distance Matching constructive algorithms, dfs and similar, trees	3200	x357
1396D	Rainbow Rectangles data structures, sortings, two pointers	3300	x312
1396C	Monster Invaders dp, greedy, implementation	2300	x2640
1396B	Stoned Game brute force, constructive algorithms, games, greedy	1800	x11590
1396A	Multiples of Length constructive algorithms, greedy, number theory	1600	x15699
1395C	Boboniu and Bit Operations bitmasks, brute force, dp, greedy	1600	x14331
1395B	Boboniu Plays Chess constructive algorithms	1100	x16112
1395A	Boboniu Likes to Color Balls brute force, math	1000	x24396
1394E	Boboniu and Banknote Collection strings	3500	x152
1394D	Boboniu and Jianghu dp, greedy, sortings, trees	2800	x1044
1394C	Boboniu and String binary search, geometry, ternary search	2600	x1130
1394B	Boboniu Walks on Graph brute force, dfs and similar, graphs, hashing	2300	x2047
1394A	Boboniu Chats with Du dp, greedy, sortings, two pointers	1800	x6855
1393E2	Twilight and Ancient Scroll (harder version) dp, hashing, implementation, string suffix structures, strings, two pointers	3200	x383
1393E1	Twilight and Ancient Scroll (easier version) dp, hashing, implementation, string suffix structures, strings	2800	x393
1393D	Rarity and New Dress dfs and similar, dp, implementation, shortest paths	2100	x4036
1393C	Pinkie Pie Eats Patty-cakes constructive algorithms, greedy, math, sortings	1700	x10706
1393B	Applejack and Storages constructive algorithms, data structures, greedy, implementation	1400	x16871
1393A	Rainbow Dash, Fluttershy and Chess Coloring greedy, math	800	x20593
1392I	Kevin and Grid fft, graphs, math	3300	x206
1392H	ZS Shuffles Cards combinatorics, dp, math, probabilities	3000	x800
1392G	Omkar and Pies bitmasks, dfs and similar, dp, math, shortest paths	2900	x524
1392F	Omkar and Landslide binary search, constructive algorithms, data structures, greedy, math	2400	x2196
1392E	Omkar and Duck bitmasks, constructive algorithms, interactive, math	2100	x3592
1392D	Omkar and Bed Wars dp, greedy	1700	x9131
1392C	Omkar and Waterslide greedy, implementation	1200	x19011
1392B	Omkar and Infinity Clock implementation, math	800	x18562
1392A	Omkar and Password greedy, math	800	x20898
1391E	Pairs of Pairs constructive algorithms, dfs and similar, graphs, greedy, trees	2600	x1737
1391D	505 bitmasks, brute force, constructive algorithms, dp, greedy, implementation	2000	x5388
1391C	Cyclic Permutations combinatorics, dp, graphs, math	1500	x15185
1391B	Fix You brute force, greedy, implementation	800	x27823
1391A	Suborrays constructive algorithms, math	800	x24542
1389G	Directing Edges dfs and similar, dp, graphs, trees	2800	x404
1389F	Bicolored Segments data structures, dp, graph matchings, sortings	2600	x1062
1389E	Calendar Ambiguity math, number theory	2200	x3492
1389D	Segment Intersections brute force, greedy, implementation, math	2100	x4362
1389C	Good String brute force, dp, greedy, two pointers	1500	x19277
1389B	Array Walk brute force, dp, greedy	1600	x17279
1389A	LCM Problem constructive algorithms, greedy, math, number theory	800	x42961
1388E	Uncle Bogdan and Projections data structures, geometry, sortings	2700	x596
1388D	Captain Flint and Treasure data structures, dfs and similar, graphs, greedy, implementation, trees	2000	x6510
1388C	Uncle Bogdan and Country Happiness dfs and similar, greedy, math, trees	1800	x9842
1388B	Captain Flint and a Long Voyage greedy, math	1000	x22385
1388A	Captain Flint and Crew Recruitment brute force, greedy, math, number theory	800	x25103
1387C	Viruses *special problem, dp, shortest paths, string suffix structures	2900	x146
1387B2	Village (Maximum) *special problem, dfs and similar, trees	2500	x967
1387B1	Village (Minimum) *special problem, dp, greedy, trees	2100	x1549
1387A	Graph *special problem, binary search, dfs and similar, dp, math, ternary search	2100	x757
1386C	Joker *special problem, bitmasks, data structures, divide and conquer, dsu	2800	x574