Problemset - Codeforces

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Codeforces Round 940 (Div. 2) and CodeCraft-23
23:56:14
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combinatorics

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Problems

#	Name
1391C	Cyclic Permutations combinatorics, dp, graphs, math	1500	x14518
1383E	Strange Operation combinatorics, data structures, dp	2800	x745
1371E2	Asterism (Hard Version) binary search, combinatorics, dp, math, number theory, sortings	2300	x2290
1371E1	Asterism (Easy Version) binary search, brute force, combinatorics, math, number theory, sortings	1900	x4945
1366E	Two Arrays binary search, brute force, combinatorics, constructive algorithms, dp, two pointers	2100	x3948
1365G	Secure Password bitmasks, combinatorics, constructive algorithms, interactive, math	2800	x911
1359E	Modular Stability combinatorics, math, number theory	2000	x5716
1342E	Placing Rooks combinatorics, fft, math	2300	x2801
1336E2	Chiori and Doll Picking (hard version) bitmasks, brute force, combinatorics, math	3500	x280
1336E1	Chiori and Doll Picking (easy version) bitmasks, brute force, combinatorics, math	2700	x645
1334E	Divisor Paths combinatorics, graphs, greedy, math, number theory	2200	x2587
1332E	Height All the Same combinatorics, constructive algorithms, math, matrices	2100	x3550
1329B	Dreamoon Likes Sequences bitmasks, combinatorics, math	1700	x6346
1328B	K-th Beautiful String binary search, brute force, combinatorics, implementation, math	1300	x28015
1327F	AND Segments bitmasks, combinatorics, data structures, dp, two pointers	2500	x1599
1327E	Count The Blocks combinatorics, dp, math	1800	x8484
1326C	Permutation Partitions combinatorics, greedy, math	1300	x15202
1312D	Count the Arrays combinatorics, math	1700	x8884
1307E	Cow and Treats binary search, combinatorics, dp, greedy, implementation, math	2500	x1073
1305C	Kuroni and Impossible Calculation brute force, combinatorics, math, number theory	1600	x13484
1301C	Ayoub's function binary search, combinatorics, greedy, math, strings	1700	x8999
1299D	Around the World bitmasks, combinatorics, dfs and similar, dp, graphs, graphs, math, trees	3000	x410
1295F	Good Contest combinatorics, dp, probabilities	2700	x980
1293B	JOE is on TV! combinatorics, greedy, math	1000	x20752
1292F	Nora's Toy Boxes bitmasks, combinatorics, dp	3500	x296
1292C	Xenon's Attack on the Gangs combinatorics, dfs and similar, dp, greedy, trees	2300	x1860
1288C	Two Arrays combinatorics, dp	1600	x12244
1285F	Classical? binary search, combinatorics, number theory	2900	x1057
1284E	New Year and Castle Construction combinatorics, geometry, math, sortings	2500	x1093
1284C	New Year and Permutation combinatorics, math	1600	x7685
1284B	New Year and Ascent Sequence binary search, combinatorics, data structures, dp, implementation, sortings	1400	x10576
1280F	Intergalactic Sliding Puzzle combinatorics, constructive algorithms, math	3400	x55
1279E	New Year Permutations combinatorics, dp	2700	x353
1279D	Santa's Bot combinatorics, math, probabilities	1700	x5860
1278F	Cards combinatorics, dp, math, number theory, probabilities	2600	x1707
1276C	Beautiful Rectangle brute force, combinatorics, constructive algorithms, data structures, greedy, math	2300	x1462
1276B	Two Fairs combinatorics, dfs and similar, dsu, graphs	1900	x4663
1272C	Yet Another Broken Keyboard combinatorics, dp, implementation	1200	x24955
1271E	Common Number binary search, combinatorics, dp, math	2100	x3105
1267K	Key Storage combinatorics, math	2100	x1737
1264D2	Beautiful Bracket Sequence (hard version) combinatorics, probabilities	2900	x837
1264D1	Beautiful Bracket Sequence (easy version) combinatorics, dp, probabilities	2600	x1165
1254E	Send Tree to Charlie combinatorics, dfs and similar, dsu, trees	3300	x258
1251F	Red-White Fence combinatorics, fft	2500	x795
1245F	Daniel and Spring Cleaning bitmasks, brute force, combinatorics, dp	2300	x1715
1239A	Ivan the Fool and the Probability Theory combinatorics, dp, math	1700	x7075
1238D	AB-string binary search, combinatorics, dp, strings	1900	x5721
1237F	Balanced Domino Placements combinatorics, dp	2600	x819
1236B	Alice and the List of Presents combinatorics, math	1500	x10614
1228E	Another Filling the Grid combinatorics, dp, math	2300	x2478
1227F2	Wrong Answer on test 233 (Hard Version) combinatorics, math	2400	x1457
1221G	Graph And Numbers bitmasks, brute force, combinatorics, dp, meet-in-the-middle	2900	x517
1215B	The Number of Products combinatorics, dp, implementation	1400	x12018
1207D	Number Of Permutations combinatorics	1800	x5764
1205E	Expected Value Again combinatorics, strings	3100	x261
1204E	Natasha, Sasha and the Prefix Sums combinatorics, dp, math, number theory	2300	x1569
1202D	Print a 1337-string... combinatorics, constructive algorithms, math, strings	1900	x4857
1197E	Culture Code binary search, combinatorics, data structures, dp, shortest paths, sortings	2300	x1448
1195D2	Submarine in the Rybinsk Sea (hard edition) combinatorics, math, number theory	1800	x4411
1195D1	Submarine in the Rybinsk Sea (easy edition) combinatorics, math, number theory	1500	x7657
1194F	Crossword Expert combinatorics, dp, number theory, probabilities, two pointers	2400	x962
1188E	Problem from Red Panda combinatorics	3300	x223
1185G2	Playlist for Polycarp (hard version) combinatorics, dp	2600	x702
1185G1	Playlist for Polycarp (easy version) bitmasks, combinatorics, dp	2100	x2548
1181C	Flag brute force, combinatorics, dp, implementation	1900	x3000
1178F1	Short Colorful Strip combinatorics, dfs and similar, dp	2200	x1897
1178C	Tiles combinatorics, greedy, math	1300	x11207
1174E	Ehab and the Expected GCD Problem combinatorics, dp, math, number theory	2500	x1345
1172B	Nauuo and Circle combinatorics, dfs and similar, dp, trees	1900	x3714
1167F	Scalar Queries combinatorics, data structures, math, sortings	2300	x1426
1167E	Range Deleting binary search, combinatorics, data structures, two pointers	2100	x2386
1166A	Silent Classroom combinatorics, greedy	900	x13802
1153F	Serval and Bonus Problem combinatorics, dp, math, probabilities	2600	x748
1151F	Sonya and Informatics combinatorics, dp, matrices, probabilities	2300	x1135
1151E	Number of Components combinatorics, data structures, dp, math	2100	x3020
1140E	Palindrome-less Arrays combinatorics, divide and conquer, dp	2200	x1881
1118F2	Tree Cutting (Hard Version) combinatorics, dfs and similar, dp, trees	2700	x499
1111D	Destroy the Colony combinatorics, dp, math	2600	x915
1109D	Sasha and Interesting Fact from Graph Theory brute force, combinatorics, dp, math, trees	2400	x1263
1105C	Ayoub and Lost Array combinatorics, dp, math	1500	x10103
1102E	Monotonic Renumeration combinatorics, sortings	1700	x5578
1097G	Vladislav and a Great Legend combinatorics, dp, trees	3000	x653
1097F	Alex and a TV Show bitmasks, combinatorics, number theory	2500	x1211
1096E	The Top Scorer combinatorics, dp, math, probabilities	2500	x857
1096B	Substring Removal combinatorics, math, strings	1300	x10318
1091D	New Year and the Permutation Concatenation combinatorics, dp, math	1700	x6579
1089I	Interval-Free Permutations combinatorics	2600	x365
1085G	Beautiful Matrix combinatorics, data structures, dp	2900	x504
1084C	The Fair Nut and String combinatorics, dp, implementation	1500	x7488
1081C	Colorful Bricks combinatorics, dp, math	1500	x6950
1073E	Segment Sum bitmasks, combinatorics, dp, math	2300	x2372
1065E	Side Transmutations combinatorics, strings	2300	x1016
1060F	Shrinking Tree combinatorics, dp	2900	x523
1043F	Make It One bitmasks, combinatorics, dp, math, number theory, shortest paths	2500	x2166
1043D	Mysterious Crime brute force, combinatorics, math, meet-in-the-middle, two pointers	1700	x4364
1037F	Maximum Reduction combinatorics, data structures, math	2500	x928
1036F	Relatively Prime Powers combinatorics, math, number theory	2400	x1353
1036C	Classy Numbers combinatorics, dp	1900	x8493
1034C	Region Separation combinatorics, dp, number theory, trees	2700	x843
1028D	Order book combinatorics, data structures, greedy	2100	x1708