Problemset - Codeforces

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

#	Name
1525D	Armchairs dp, flows, graph matchings, greedy	1800	x9966
1525C	Robot Collisions data structures, greedy, implementation, sortings	2000	x4538
1525B	Permutation Sort constructive algorithms, greedy	900	x25199
1525A	Potion-making math, number theory	800	x25779
1523H	Hopping Around the Array data structures, dp	3500	x311
1523G	Try Booking data structures, divide and conquer	3200	x473
1523F	Favorite Game bitmasks, dp	3300	x438
1523E	Crypto Lights combinatorics, dp, math, probabilities	2600	x1737
1523D	Love-Hate bitmasks, brute force, dp, probabilities	2400	x2233
1523C	Compression and Expansion brute force, data structures, greedy, implementation, trees	1600	x8888
1523B	Lord of the Values constructive algorithms	1100	x12156
1523A	Game of Life implementation	800	x13562
1521E	Nastia and a Beautiful Matrix binary search, constructive algorithms, dp, greedy	2700	x683
1521D	Nastia Plays with a Tree constructive algorithms, data structures, dfs and similar, dp, dsu, greedy, implementation, trees	2500	x2008
1521C	Nastia and a Hidden Permutation constructive algorithms, interactive	2000	x4406
1521B	Nastia and a Good Array constructive algorithms, math, number theory	1300	x21693
1521A	Nastia and Nearly Good Numbers constructive algorithms, math, number theory	1000	x38285
1520G	To Go Or Not To Go? brute force, dfs and similar, graphs, greedy, implementation, shortest paths	2200	x3795
1520F2	Guess the K-th Zero (Hard version) binary search, constructive algorithms, data structures, interactive	2200	x3077
1520F1	Guess the K-th Zero (Easy version) binary search, interactive	1600	x12363
1520E	Arranging The Sheep greedy, math	1400	x22342
1520D	Same Differences data structures, hashing, math	1200	x49593
1520C	Not Adjacent Matrix constructive algorithms	1000	x32328
1520B	Ordinary Numbers brute force, math, number theory	800	x45456
1520A	Do Not Be Distracted! brute force, implementation	800	x53128
1519F	Chests and Keys bitmasks, brute force, dfs and similar, dp, flows	3200	x506
1519E	Off by One constructive algorithms, dfs and similar, geometry, graphs, sortings, trees	2700	x832
1519D	Maximum Sum of Products brute force, dp, implementation, math, two pointers	1600	x15652
1519C	Berland Regional brute force, data structures, greedy, number theory, sortings	1400	x17573
1519B	The Cake Is a Lie dp, math	800	x31301
1519A	Red and Blue Beans math	800	x29239
1517H	Fly Around the World dp, geometry	3500	x75
1517G	Starry Night Camping constructive algorithms, flows, graphs	3300	x523
1517F	Reunion combinatorics, dp, trees	3200	x479
1517E	Group Photo binary search, data structures, implementation, two pointers	2500	x993
1517D	Explorer Space dp, graphs, shortest paths	1800	x7981
1517C	Fillomino 2 constructive algorithms, dfs and similar, greedy, implementation	1400	x13517
1517B	Morning Jogging constructive algorithms, greedy, sortings	1200	x13358
1517A	Sum of 2050 greedy, math	800	x25804
1516E	Baby Ehab Plays with Permutations combinatorics, dp, math	2500	x901
1516D	Cut binary search, data structures, dp, graphs, number theory, two pointers	2100	x4532
1516C	Baby Ehab Partitions Again bitmasks, constructive algorithms, dp, math	1700	x12169
1516B	AGAGA XOOORRR bitmasks, brute force, dp, greedy	1500	x20202
1516A	Tit for Tat greedy	800	x23691
1515I	Phoenix and Diamonds binary search, data structures, sortings	3400	x297
1515H	Phoenix and Bits bitmasks, brute force, data structures, sortings	3500	x257
1515G	Phoenix and Odometers dfs and similar, graphs, math, number theory	2700	x1053
1515F	Phoenix and Earthquake constructive algorithms, dfs and similar, dsu, graphs, greedy, trees	2600	x1852
1515E	Phoenix and Computers combinatorics, dp, math	2200	x3739
1515D	Phoenix and Socks greedy, sortings, two pointers	1500	x11567
1515C	Phoenix and Towers constructive algorithms, data structures, greedy	1400	x17447
1515B	Phoenix and Puzzle brute force, geometry, math, number theory	1000	x25353
1515A	Phoenix and Gold constructive algorithms, greedy, math	800	x20370
1514E	Baby Ehab's Hyper Apartment binary search, graphs, interactive, sortings, two pointers	2700	x633
1514D	Cut and Stick binary search, data structures, greedy, implementation, sortings	2000	x4409
1514C	Product 1 Modulo N greedy, number theory	1600	x15647
1514B	AND 0, Sum Big bitmasks, combinatorics, math	1200	x26401
1514A	Perfectly Imperfect Array math, number theory	800	x24424
1513F	Swapping Problem brute force, constructive algorithms, data structures, sortings	2500	x1298
1513E	Cost Equilibrium combinatorics, constructive algorithms, math, sortings	2300	x1544
1513D	GCD and MST constructive algorithms, dsu, graphs, greedy, number theory, sortings	2000	x5641
1513C	Add One dp, matrices	1600	x14586
1513B	AND Sequences bitmasks, combinatorics, constructive algorithms, math	1400	x15357
1513A	Array and Peaks constructive algorithms, implementation	800	x19498
1512G	Short Task brute force, dp, math, number theory	1700	x8415
1512F	Education brute force, dp, greedy, implementation	1900	x6343
1512E	Permutation by Sum brute force, greedy, math	1600	x10665
1512D	Corrupted Array constructive algorithms, data structures, greedy	1200	x22925
1512C	A-B Palindrome constructive algorithms, implementation, strings	1200	x20495
1512B	Almost Rectangle implementation	800	x25657
1512A	Spy Detected! brute force, implementation	800	x66889
1511G	Chips on a Board bitmasks, brute force, data structures, dp, games, two pointers	2700	x827
1511F	Chainword brute force, data structures, dp, matrices, string suffix structures, strings	2700	x454
1511E	Colorings and Dominoes combinatorics, dp, greedy, math	2100	x2635
1511D	Min Cost String brute force, constructive algorithms, graphs, greedy, strings	1600	x11705
1511C	Yet Another Card Deck brute force, data structures, implementation, trees	1100	x24854
1511B	GCD Length constructive algorithms, math, number theory	1100	x23217
1511A	Review Site greedy	800	x27864
1510K	King's Task brute force, graphs, implementation	1200	x5578
1510J	Japanese Game constructive algorithms, math	2700	x533
1510I	Is It Rated? greedy, interactive, math, probabilities	2700	x508
1510H	Hard Optimization dp	3200	x101
1510G	Guide	2100	x1323
1510F	Fiber Shape	2800	x59
1510E	Equilibrium Point /\textbackslash/\textbackslash	2700	x260
1510D	Digits dp, math, number theory	2100	x1965
1510C	Cactus Not Enough dfs and similar, graph matchings, graphs	2900	x222
1510B	Button Lock flows, graph matchings, graphs	2600	x873
1510A	ASCII Automata Art	3100	x158
1509C	The Sports Festival dp, greedy	1800	x13058
1509B	TMT Document greedy	1100	x21888
1509A	Average Height constructive algorithms	800	x26167
1508F	Optimal Encoding brute force, data structures	3500	x128
1508E	Tree Calendar brute force, constructive algorithms, data structures, dfs and similar, sortings, trees	3100	x356
1508D	Swap Pass constructive algorithms, geometry, sortings	3000	x597
1508C	Complete the MST bitmasks, brute force, data structures, dfs and similar, dsu, graphs, greedy, trees	2500	x1540
1508B	Almost Sorted binary search, combinatorics, constructive algorithms, implementation	1800	x4078
1508A	Binary Literature constructive algorithms, greedy, implementation, strings, two pointers	1900	x6333
1506G	Maximize the Remaining String brute force, data structures, dp, greedy, strings	2000	x4424
1506F	Triangular Paths constructive algorithms, graphs, math, shortest paths, sortings	2000	x3355