Problemset - Codeforces

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Codeforces Round (Div. 3)
4 days

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Difficulty: —

combinatorics

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Problems

#	Name
1450H1	Multithreading (Easy Version) combinatorics, fft, math	2900	x383
1444B	Divide and Sum combinatorics, math, sortings	1900	x6102
1442B	Identify the Operations combinatorics, data structures, dsu, greedy, implementation	1800	x4380
1439D	INOI Final Contests combinatorics, dp, fft	3100	x351
1437F	Emotional Fishermen combinatorics, dp, math, two pointers	2600	x1181
1436F	Sum Over Subsets combinatorics, math, number theory	2800	x511
1436C	Binary Search binary search, combinatorics	1500	x10645
1433E	Two Round Dances combinatorics, math	1300	x18181
1426F	Number of Subsequences combinatorics, dp, strings	2000	x5181
1425D	Danger of Mad Snakes combinatorics, dp, math	2300	x816
1422C	Bargain combinatorics, dp, math	1700	x8143
1420D	Rescue Nibel! combinatorics, data structures, sortings	1800	x7451
1418E	Expected Damage binary search, combinatorics, probabilities	2400	x1755
1408G	Clusterization Counting combinatorics, dp, dsu, fft, graphs, trees	2700	x936
1403C	Chess Rush *special problem, combinatorics, dp, implementation, math	3200	x47
1402C	Star Trek *special problem, combinatorics, dfs and similar, dp, games, graphs, matrices, trees	2600	x201
1400G	Mercenaries bitmasks, brute force, combinatorics, dp, dsu, math, two pointers	2600	x940
1400D	Zigzags brute force, combinatorics, data structures, math, two pointers	1900	x9937
1392H	ZS Shuffles Cards combinatorics, dp, math, probabilities	3000	x692
1391C	Cyclic Permutations combinatorics, dp, graphs, math	1500	x14711
1383E	Strange Operation combinatorics, data structures, dp	2800	x760
1371E2	Asterism (Hard Version) binary search, combinatorics, dp, math, number theory, sortings	2300	x2313
1371E1	Asterism (Easy Version) binary search, brute force, combinatorics, math, number theory, sortings	1900	x5041
1366E	Two Arrays binary search, brute force, combinatorics, constructive algorithms, dp, two pointers	2100	x4053
1365G	Secure Password bitmasks, combinatorics, constructive algorithms, interactive, math	2800	x972
1359E	Modular Stability combinatorics, math, number theory	2000	x5859
1342E	Placing Rooks combinatorics, fft, math	2300	x3020
1336E2	Chiori and Doll Picking (hard version) bitmasks, brute force, combinatorics, math	3500	x295
1336E1	Chiori and Doll Picking (easy version) bitmasks, brute force, combinatorics, math	2700	x656
1334E	Divisor Paths combinatorics, graphs, greedy, math, number theory	2200	x2791
1332E	Height All the Same combinatorics, constructive algorithms, math, matrices	2100	x3775
1329B	Dreamoon Likes Sequences bitmasks, combinatorics, math	1700	x6588
1328B	K-th Beautiful String binary search, brute force, combinatorics, implementation, math	1300	x28585
1327F	AND Segments bitmasks, combinatorics, data structures, dp, two pointers	2500	x1619
1327E	Count The Blocks combinatorics, dp, math	1800	x8808
1326C	Permutation Partitions combinatorics, greedy, math	1300	x15510
1312D	Count the Arrays combinatorics, math	1700	x9221
1307E	Cow and Treats binary search, combinatorics, dp, greedy, implementation, math	2500	x1263
1305C	Kuroni and Impossible Calculation brute force, combinatorics, math, number theory	1600	x14138
1301C	Ayoub's function binary search, combinatorics, greedy, math, strings	1700	x9244
1299D	Around the World bitmasks, combinatorics, dfs and similar, dp, graphs, graphs, math, trees	3000	x424
1295F	Good Contest combinatorics, dp, probabilities	2700	x1172
1293B	JOE is on TV! combinatorics, greedy, math	1000	x21081
1292F	Nora's Toy Boxes bitmasks, combinatorics, dp	3500	x309
1292C	Xenon's Attack on the Gangs combinatorics, dfs and similar, dp, greedy, trees	2300	x2023
1288C	Two Arrays combinatorics, dp	1600	x12584
1285F	Classical? binary search, combinatorics, number theory	2900	x1094
1284E	New Year and Castle Construction combinatorics, geometry, math, sortings	2500	x1288
1284C	New Year and Permutation combinatorics, math	1600	x7930
1284B	New Year and Ascent Sequence binary search, combinatorics, data structures, dp, implementation, sortings	1400	x10777
1280F	Intergalactic Sliding Puzzle combinatorics, constructive algorithms, math	3400	x59
1279E	New Year Permutations combinatorics, dp	2700	x358
1279D	Santa's Bot combinatorics, math, probabilities	1700	x6139
1278F	Cards combinatorics, dp, math, number theory, probabilities	2600	x1783
1276C	Beautiful Rectangle brute force, combinatorics, constructive algorithms, data structures, greedy, math	2300	x1632
1276B	Two Fairs combinatorics, dfs and similar, dsu, graphs	1900	x4838
1272C	Yet Another Broken Keyboard combinatorics, dp, implementation	1200	x25843
1271E	Common Number binary search, combinatorics, dp, math	2100	x3328
1267K	Key Storage combinatorics, math	2100	x1877
1264D2	Beautiful Bracket Sequence (hard version) combinatorics, probabilities	2900	x860
1264D1	Beautiful Bracket Sequence (easy version) combinatorics, dp, probabilities	2600	x1189
1254E	Send Tree to Charlie combinatorics, dfs and similar, dsu, trees	3300	x263
1251F	Red-White Fence combinatorics, fft	2500	x804
1245F	Daniel and Spring Cleaning bitmasks, brute force, combinatorics, dp	2300	x1796
1239A	Ivan the Fool and the Probability Theory combinatorics, dp, math	1700	x7245
1238D	AB-string binary search, combinatorics, dp, strings	1900	x5905
1237F	Balanced Domino Placements combinatorics, dp	2600	x835
1236B	Alice and the List of Presents combinatorics, math	1500	x10923
1228E	Another Filling the Grid combinatorics, dp, math	2300	x2578
1227F2	Wrong Answer on test 233 (Hard Version) combinatorics, math	2400	x1473
1221G	Graph And Numbers bitmasks, brute force, combinatorics, dp, meet-in-the-middle	2900	x544
1215B	The Number of Products combinatorics, dp, implementation	1400	x12486
1207D	Number Of Permutations combinatorics	1800	x6003
1205E	Expected Value Again combinatorics, strings	3100	x273
1204E	Natasha, Sasha and the Prefix Sums combinatorics, dp, math, number theory	2300	x1609
1202D	Print a 1337-string... combinatorics, constructive algorithms, math, strings	1900	x5049
1197E	Culture Code binary search, combinatorics, data structures, dp, shortest paths, sortings	2300	x1616
1195D2	Submarine in the Rybinsk Sea (hard edition) combinatorics, math, number theory	1800	x4572
1195D1	Submarine in the Rybinsk Sea (easy edition) combinatorics, math, number theory	1500	x7812
1194F	Crossword Expert combinatorics, dp, number theory, probabilities, two pointers	2400	x980
1188E	Problem from Red Panda combinatorics	3300	x227
1185G2	Playlist for Polycarp (hard version) combinatorics, dp	2600	x726
1185G1	Playlist for Polycarp (easy version) bitmasks, combinatorics, dp	2100	x2808
1181C	Flag brute force, combinatorics, dp, implementation	1900	x3030
1178F1	Short Colorful Strip combinatorics, dfs and similar, dp	2200	x2072
1178C	Tiles combinatorics, greedy, math	1300	x11550
1174E	Ehab and the Expected GCD Problem combinatorics, dp, math, number theory	2500	x1380
1172B	Nauuo and Circle combinatorics, dfs and similar, dp, trees	1900	x3936
1167F	Scalar Queries combinatorics, data structures, math, sortings	2300	x1592
1167E	Range Deleting binary search, combinatorics, data structures, two pointers	2100	x2571
1166A	Silent Classroom combinatorics, greedy	900	x14065
1153F	Serval and Bonus Problem combinatorics, dp, math, probabilities	2600	x765
1151F	Sonya and Informatics combinatorics, dp, matrices, probabilities	2300	x1159
1151E	Number of Components combinatorics, data structures, dp, math	2100	x3195
1140E	Palindrome-less Arrays combinatorics, divide and conquer, dp	2200	x1904
1118F2	Tree Cutting (Hard Version) combinatorics, dfs and similar, dp, trees	2700	x525
1111D	Destroy the Colony combinatorics, dp, math	2600	x934
1109D	Sasha and Interesting Fact from Graph Theory brute force, combinatorics, dp, math, trees	2400	x1275
1105C	Ayoub and Lost Array combinatorics, dp, math	1500	x10223
1102E	Monotonic Renumeration combinatorics, sortings	1700	x5767