Problemset - Codeforces

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Codeforces Round 940 (Div. 2) and CodeCraft-23
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combinatorics

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Problems

#	Name
1608D	Dominoes combinatorics, fft, graphs, math, number theory	2400	x1343
1606E	Arena combinatorics, dp, math	2100	x3320
1605F	PalindORme combinatorics, dp	2900	x283
1603F	October 18, 2017 combinatorics, dp, implementation, math	2700	x260
1603E	A Perfect Problem combinatorics, dp, math	3200	x393
1599C	Bubble Strike combinatorics, math, probabilities, ternary search	2000	x1546
1598E	Staircases brute force, combinatorics, data structures, dfs and similar, dp, implementation, math	2100	x2224
1598D	Training Session combinatorics, data structures, geometry, implementation, math	1700	x8369
1594E1	Rubik's Cube Coloring (easy version) combinatorics, math	1300	x10826
1586I	Omkar and Mosaic combinatorics, constructive algorithms, math	3500	x154
1585F	Non-equal Neighbours combinatorics, dp, math	2400	x1147
1584D	Guess the Permutation binary search, combinatorics, interactive, math	2000	x3505
1582B	Luntik and Subsequences combinatorics, math	900	x18647
1581A	CQXYM Count Permutations combinatorics, math, number theory	800	x13223
1580F	Problems for Codeforces combinatorics, fft, math	3300	x129
1580B	Mathematics Curriculum brute force, combinatorics, dp, trees	2600	x961
1574F	Occurrences combinatorics, dfs and similar, dp, dsu, fft, graphs	2700	x569
1574E	Coloring combinatorics, constructive algorithms, implementation, math	2500	x857
1574B	Combinatorics Homework combinatorics, greedy, math	1100	x16973
1569C	Jury Meeting combinatorics, math	1500	x11618
1567C	Carrying Conundrum bitmasks, combinatorics, dp, math	1600	x11795
1559E	Mocha and Stars combinatorics, dp, fft, math, number theory	2200	x2210
1558D	Top-Notch Insertions combinatorics, data structures	2600	x919
1557C	Moamen and XOR bitmasks, combinatorics, dp, math, matrices	1700	x8293
1556F	Sports Betting bitmasks, combinatorics, dp, graphs, math, probabilities	2500	x1157
1553I	Stairs combinatorics, divide and conquer, dp, fft, math	3400	x194
1553E	Permutation Shift brute force, combinatorics, constructive algorithms, dfs and similar, dsu, graphs, math	2100	x3227
1552C	Maximize the Intersections combinatorics, constructive algorithms, geometry, greedy, sortings	1800	x5763
1552B	Running for Gold combinatorics, graphs, greedy, sortings	1500	x14924
1551F	Equidistant Vertices brute force, combinatorics, dfs and similar, dp, trees	2200	x1736
1550D	Excellent Arrays binary search, combinatorics, constructive algorithms, implementation, math, sortings, two pointers	2300	x1778
1548C	The Three Little Pigs combinatorics, dp, fft, math	2500	x1732
1545C	AquaMoon and Permutations 2-sat, brute force, combinatorics, constructive algorithms, graph matchings, graphs	2800	x578
1545B	AquaMoon and Chess combinatorics, math	1900	x5598
1543B	Customising the Track combinatorics, greedy, math	900	x22606
1542E2	Abnormal Permutation Pairs (hard version) combinatorics, dp, fft, math	2700	x800
1542E1	Abnormal Permutation Pairs (easy version) combinatorics, dp, fft, math	2400	x1179
1542D	Priority Queue combinatorics, dp, implementation, math, ternary search	2200	x2524
1540B	Tree Array brute force, combinatorics, dp, graphs, math, probabilities, trees	2300	x2480
1539A	Contest Start combinatorics, geometry, greedy, math	1000	x19551
1536F	Omkar and Akmar chinese remainder theorem, combinatorics, constructive algorithms, fft, games, geometry, math, meet-in-the-middle, string suffix structures	2600	x908
1536E	Omkar and Forest combinatorics, graphs, math, shortest paths	2300	x2332
1534C	Little Alawn's Puzzle combinatorics, dp, dsu, graphs, math	1300	x12460
1530F	Bingo bitmasks, combinatorics, dp, math, probabilities	2600	x744
1528F	AmShZ Farm combinatorics, fft, math	3300	x271
1528E	Mashtali and Hagh Trees combinatorics, dp, trees	2900	x500
1528B	Kavi on Pairing Duty combinatorics, dp, math	1700	x8433
1527D	MEX Tree combinatorics, dfs and similar, implementation, math, trees	2400	x1815
1526E	Oolimry and Suffix Array combinatorics, constructive algorithms, math	2400	x1015
1525E	Assimilation IV combinatorics, dp, math, probabilities, two pointers	2100	x1930
1523E	Crypto Lights combinatorics, dp, math, probabilities	2600	x1521
1517F	Reunion combinatorics, dp, trees	3200	x434
1516E	Baby Ehab Plays with Permutations combinatorics, dp, math	2500	x808
1515E	Phoenix and Computers combinatorics, dp, math	2200	x3343
1514B	AND 0, Sum Big bitmasks, combinatorics, math	1200	x22472
1513E	Cost Equilibrium combinatorics, constructive algorithms, math, sortings	2300	x1408
1513B	AND Sequences bitmasks, combinatorics, constructive algorithms, math	1400	x13646
1511E	Colorings and Dominoes combinatorics, dp, greedy, math	2100	x2442
1508B	Almost Sorted binary search, combinatorics, constructive algorithms, implementation	1800	x3819
1503E	2-Coloring combinatorics, dp, math	3100	x587
1499F	Diameter Cuts combinatorics, dfs and similar, dp, trees	2400	x1234
1499E	Chaotic Merge combinatorics, dp, math, strings	2400	x1401
1499A	Domino on Windowsill combinatorics, constructive algorithms, math	800	x20991
1495D	BFS Trees combinatorics, dfs and similar, graphs, math, shortest paths, trees	2600	x1187
1488H	Build From Suffixes *special problem, combinatorics, data structures	2800	x52
1487G	String Counting combinatorics, dp, fft, math	2700	x571
1486F	Pairs of Paths combinatorics, data structures, dfs and similar, dp, trees	2600	x619
1485F	Copy or Prefix Sum combinatorics, data structures, dp, sortings	2400	x1858
1477F	Nezzar and Chocolate Bars combinatorics, fft, math, probabilities	3500	x120
1475E	Advertising Agency combinatorics, math, sortings	1600	x12808
1475C	Ball in Berland combinatorics, graphs, math	1400	x19859
1473G	Tiles combinatorics, dp, fft, math	2800	x377
1470E	Strange Permutation binary search, combinatorics, data structures, dp, graphs, implementation, two pointers	3200	x289
1467D	Sum of Paths combinatorics, dp, math	2200	x3532
1466H	Finding satisfactory solutions combinatorics, dp, graphs, greedy, math	3300	x255
1466G	Song of the Sirens combinatorics, divide and conquer, hashing, math, string suffix structures, strings	2600	x840
1462E2	Close Tuples (hard version) binary search, combinatorics, implementation, math, sortings, two pointers	1700	x9176
1462E1	Close Tuples (easy version) binary search, combinatorics, math, sortings, two pointers	1500	x13151
1454E	Number of Simple Paths combinatorics, dfs and similar, graphs, trees	2000	x5484
1452D	Radio Towers combinatorics, dp, math	1600	x7739
1450H2	Multithreading (Hard Version) combinatorics, implementation, math	3300	x161
1450H1	Multithreading (Easy Version) combinatorics, fft, math	2900	x372
1444B	Divide and Sum combinatorics, math, sortings	1900	x6013
1442B	Identify the Operations combinatorics, data structures, dsu, greedy, implementation	1800	x4293
1439D	INOI Final Contests combinatorics, dp, fft	3100	x336
1437F	Emotional Fishermen combinatorics, dp, math, two pointers	2600	x1158
1436F	Sum Over Subsets combinatorics, math, number theory	2800	x484
1436C	Binary Search binary search, combinatorics	1500	x10503
1433E	Two Round Dances combinatorics, math	1300	x17969
1426F	Number of Subsequences combinatorics, dp, strings	2000	x5079
1425D	Danger of Mad Snakes combinatorics, dp, math	2300	x801
1422C	Bargain combinatorics, dp, math	1700	x8060
1420D	Rescue Nibel! combinatorics, data structures, sortings	1800	x7286
1418E	Expected Damage binary search, combinatorics, probabilities	2400	x1714
1408G	Clusterization Counting combinatorics, dp, dsu, fft, graphs, trees	2700	x917
1403C	Chess Rush *special problem, combinatorics, dp, implementation, math	3200	x42
1402C	Star Trek *special problem, combinatorics, dfs and similar, dp, games, graphs, matrices, trees	2600	x195
1400G	Mercenaries bitmasks, brute force, combinatorics, dp, dsu, math, two pointers	2600	x886
1400D	Zigzags brute force, combinatorics, data structures, math, two pointers	1900	x9764
1392H	ZS Shuffles Cards combinatorics, dp, math, probabilities	3000	x666