Problemset - Codeforces

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Educational Codeforces Round 166 (Rated for Div. 2)
43:37:49
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combinatorics

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Problems

#	Name
1620G	Subsequences Galore bitmasks, combinatorics, dp	2400	x862
1616H	Keep XOR Low bitmasks, combinatorics, data structures, divide and conquer, dp, math	3000	x802
1615F	LEGOndary Grandmaster combinatorics, dp, math	2800	x763
1614C	Divan and bitwise operations bitmasks, combinatorics, constructive algorithms, dp, math	1500	x9955
1613F	Tree Coloring combinatorics, divide and conquer, fft	2600	x667
1612G	Max Sum Array combinatorics, constructive algorithms, greedy, sortings	2500	x817
1610D	Not Quite Lee combinatorics, dp, math, number theory	2000	x2598
1608F	MEX counting combinatorics, dp, implementation	3200	x521
1608D	Dominoes combinatorics, fft, graphs, math, number theory	2400	x1354
1606E	Arena combinatorics, dp, math	2100	x3360
1605F	PalindORme combinatorics, dp	2900	x291
1603F	October 18, 2017 combinatorics, dp, implementation, math	2700	x268
1603E	A Perfect Problem combinatorics, dp, math	3200	x403
1599C	Bubble Strike combinatorics, math, probabilities, ternary search	2000	x1566
1598E	Staircases brute force, combinatorics, data structures, dfs and similar, dp, implementation, math	2100	x2249
1598D	Training Session combinatorics, data structures, geometry, implementation, math	1700	x8429
1594E1	Rubik's Cube Coloring (easy version) combinatorics, math	1300	x10903
1586I	Omkar and Mosaic combinatorics, constructive algorithms, math	3500	x161
1585F	Non-equal Neighbours combinatorics, dp, math	2400	x1154
1584D	Guess the Permutation binary search, combinatorics, interactive, math	2000	x3568
1582B	Luntik and Subsequences combinatorics, math	900	x19048
1581A	CQXYM Count Permutations combinatorics, math, number theory	800	x13277
1580F	Problems for Codeforces combinatorics, fft, math	3300	x130
1580B	Mathematics Curriculum brute force, combinatorics, dp, trees	2600	x982
1574F	Occurrences combinatorics, dfs and similar, dp, dsu, fft, graphs	2700	x589
1574E	Coloring combinatorics, constructive algorithms, implementation, math	2500	x875
1574B	Combinatorics Homework combinatorics, greedy, math	1100	x17069
1569C	Jury Meeting combinatorics, math	1500	x11698
1567C	Carrying Conundrum bitmasks, combinatorics, dp, math	1600	x11878
1559E	Mocha and Stars combinatorics, dp, fft, math, number theory	2200	x2222
1558D	Top-Notch Insertions combinatorics, data structures	2600	x927
1557C	Moamen and XOR bitmasks, combinatorics, dp, math, matrices	1700	x8360
1556F	Sports Betting bitmasks, combinatorics, dp, graphs, math, probabilities	2500	x1181
1553I	Stairs combinatorics, divide and conquer, dp, fft, math	3400	x196
1553E	Permutation Shift brute force, combinatorics, constructive algorithms, dfs and similar, dsu, graphs, math	2100	x3249
1552C	Maximize the Intersections combinatorics, constructive algorithms, geometry, greedy, sortings	1800	x5784
1552B	Running for Gold combinatorics, graphs, greedy, sortings	1500	x15023
1551F	Equidistant Vertices brute force, combinatorics, dfs and similar, dp, trees	2200	x1758
1550D	Excellent Arrays binary search, combinatorics, constructive algorithms, implementation, math, sortings, two pointers	2300	x1790
1548C	The Three Little Pigs combinatorics, dp, fft, math	2500	x1741
1545C	AquaMoon and Permutations 2-sat, brute force, combinatorics, constructive algorithms, graph matchings, graphs	2800	x586
1545B	AquaMoon and Chess combinatorics, math	1900	x5668
1543B	Customising the Track combinatorics, greedy, math	900	x22713
1542E2	Abnormal Permutation Pairs (hard version) combinatorics, dp, fft, math	2700	x813
1542E1	Abnormal Permutation Pairs (easy version) combinatorics, dp, fft, math	2400	x1192
1542D	Priority Queue combinatorics, dp, implementation, math, ternary search	2200	x2539
1540B	Tree Array brute force, combinatorics, dp, graphs, math, probabilities, trees	2300	x2503
1539A	Contest Start combinatorics, geometry, greedy, math	1000	x19654
1536F	Omkar and Akmar chinese remainder theorem, combinatorics, constructive algorithms, fft, games, geometry, math, meet-in-the-middle, string suffix structures	2600	x916
1536E	Omkar and Forest combinatorics, graphs, math, shortest paths	2300	x2350
1534C	Little Alawn's Puzzle combinatorics, dp, dsu, graphs, math	1300	x12536
1530F	Bingo bitmasks, combinatorics, dp, math, probabilities	2600	x754
1528F	AmShZ Farm combinatorics, fft, math	3300	x276
1528E	Mashtali and Hagh Trees combinatorics, dp, trees	2900	x510
1528B	Kavi on Pairing Duty combinatorics, dp, math	1700	x8503
1527D	MEX Tree combinatorics, dfs and similar, implementation, math, trees	2400	x1840
1526E	Oolimry and Suffix Array combinatorics, constructive algorithms, math	2400	x1030
1525E	Assimilation IV combinatorics, dp, math, probabilities, two pointers	2100	x1973
1523E	Crypto Lights combinatorics, dp, math, probabilities	2600	x1540
1517F	Reunion combinatorics, dp, trees	3200	x446
1516E	Baby Ehab Plays with Permutations combinatorics, dp, math	2500	x816
1515E	Phoenix and Computers combinatorics, dp, math	2200	x3389
1514B	AND 0, Sum Big bitmasks, combinatorics, math	1200	x23040
1513E	Cost Equilibrium combinatorics, constructive algorithms, math, sortings	2300	x1418
1513B	AND Sequences bitmasks, combinatorics, constructive algorithms, math	1400	x13876
1511E	Colorings and Dominoes combinatorics, dp, greedy, math	2100	x2469
1508B	Almost Sorted binary search, combinatorics, constructive algorithms, implementation	1800	x3853
1503E	2-Coloring combinatorics, dp, math	3100	x595
1499F	Diameter Cuts combinatorics, dfs and similar, dp, trees	2400	x1254
1499E	Chaotic Merge combinatorics, dp, math, strings	2400	x1413
1499A	Domino on Windowsill combinatorics, constructive algorithms, math	800	x21036
1495D	BFS Trees combinatorics, dfs and similar, graphs, math, shortest paths, trees	2600	x1196
1488H	Build From Suffixes *special problem, combinatorics, data structures	2800	x54
1487G	String Counting combinatorics, dp, fft, math	2700	x578
1486F	Pairs of Paths combinatorics, data structures, dfs and similar, dp, trees	2600	x626
1485F	Copy or Prefix Sum combinatorics, data structures, dp, sortings	2400	x1872
1477F	Nezzar and Chocolate Bars combinatorics, fft, math, probabilities	3500	x123
1475E	Advertising Agency combinatorics, math, sortings	1600	x12964
1475C	Ball in Berland combinatorics, graphs, math	1400	x20104
1473G	Tiles combinatorics, dp, fft, math	2800	x382
1470E	Strange Permutation binary search, combinatorics, data structures, dp, graphs, implementation, two pointers	3200	x293
1467D	Sum of Paths combinatorics, dp, math	2200	x3546
1466H	Finding satisfactory solutions combinatorics, dp, graphs, greedy, math	3300	x264
1466G	Song of the Sirens combinatorics, divide and conquer, hashing, math, string suffix structures, strings	2600	x853
1462E2	Close Tuples (hard version) binary search, combinatorics, implementation, math, sortings, two pointers	1700	x9248
1462E1	Close Tuples (easy version) binary search, combinatorics, math, sortings, two pointers	1500	x13246
1454E	Number of Simple Paths combinatorics, dfs and similar, graphs, trees	2000	x5529
1452D	Radio Towers combinatorics, dp, math	1600	x7784
1450H2	Multithreading (Hard Version) combinatorics, implementation, math	3300	x165
1450H1	Multithreading (Easy Version) combinatorics, fft, math	2900	x375
1444B	Divide and Sum combinatorics, math, sortings	1900	x6065
1442B	Identify the Operations combinatorics, data structures, dsu, greedy, implementation	1800	x4323
1439D	INOI Final Contests combinatorics, dp, fft	3100	x342
1437F	Emotional Fishermen combinatorics, dp, math, two pointers	2600	x1173
1436F	Sum Over Subsets combinatorics, math, number theory	2800	x500
1436C	Binary Search binary search, combinatorics	1500	x10559
1433E	Two Round Dances combinatorics, math	1300	x18079
1426F	Number of Subsequences combinatorics, dp, strings	2000	x5139
1425D	Danger of Mad Snakes combinatorics, dp, math	2300	x805
1422C	Bargain combinatorics, dp, math	1700	x8101