Problemset - Codeforces

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combinatorics

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Problems

#	Name
1454E	Number of Simple Paths combinatorics, dfs and similar, graphs, trees	2000	x5621
1452D	Radio Towers combinatorics, dp, math	1600	x7821
1450H2	Multithreading (Hard Version) combinatorics, implementation, math	3300	x170
1450H1	Multithreading (Easy Version) combinatorics, fft, math	2900	x383
1444B	Divide and Sum combinatorics, math, sortings	1900	x6157
1442B	Identify the Operations combinatorics, data structures, dsu, greedy, implementation	1800	x4420
1439D	INOI Final Contests combinatorics, dp, fft	3100	x353
1437F	Emotional Fishermen combinatorics, dp, math, two pointers	2600	x1186
1436F	Sum Over Subsets combinatorics, math, number theory	2800	x512
1436C	Binary Search binary search, combinatorics	1500	x10711
1433E	Two Round Dances combinatorics, math	1300	x18196
1426F	Number of Subsequences combinatorics, dp, strings	2000	x5199
1425D	Danger of Mad Snakes combinatorics, dp, math	2300	x818
1422C	Bargain combinatorics, dp, math	1700	x8151
1420D	Rescue Nibel! combinatorics, data structures, sortings	1800	x7457
1418E	Expected Damage binary search, combinatorics, probabilities	2400	x1808
1408G	Clusterization Counting combinatorics, dp, dsu, fft, graphs, trees	2700	x986
1403C	Chess Rush *special problem, combinatorics, dp, implementation, math	3200	x48
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	x944
1400D	Zigzags brute force, combinatorics, data structures, math, two pointers	1900	x9990
1392H	ZS Shuffles Cards combinatorics, dp, math, probabilities	3000	x692
1391C	Cyclic Permutations combinatorics, dp, graphs, math	1500	x14724
1383E	Strange Operation combinatorics, data structures, dp	2800	x761
1371E2	Asterism (Hard Version) binary search, combinatorics, dp, math, number theory, sortings	2300	x2315
1371E1	Asterism (Easy Version) binary search, brute force, combinatorics, math, number theory, sortings	1900	x5052
1366E	Two Arrays binary search, brute force, combinatorics, constructive algorithms, dp, two pointers	2100	x4062
1365G	Secure Password bitmasks, combinatorics, constructive algorithms, interactive, math	2800	x1043
1359E	Modular Stability combinatorics, math, number theory	2000	x6011
1342E	Placing Rooks combinatorics, fft, math	2300	x3029
1336E2	Chiori and Doll Picking (hard version) bitmasks, brute force, combinatorics, math	3500	x297
1336E1	Chiori and Doll Picking (easy version) bitmasks, brute force, combinatorics, math	2700	x658
1334E	Divisor Paths combinatorics, graphs, greedy, math, number theory	2200	x2794
1332E	Height All the Same combinatorics, constructive algorithms, math, matrices	2100	x3783
1329B	Dreamoon Likes Sequences bitmasks, combinatorics, math	1700	x6596
1328B	K-th Beautiful String binary search, brute force, combinatorics, implementation, math	1300	x28701
1327F	AND Segments bitmasks, combinatorics, data structures, dp, two pointers	2500	x1620
1327E	Count The Blocks combinatorics, dp, math	1800	x8822
1326C	Permutation Partitions combinatorics, greedy, math	1300	x15521
1312D	Count the Arrays combinatorics, math	1700	x9242
1307E	Cow and Treats binary search, combinatorics, dp, greedy, implementation, math	2500	x1266
1305C	Kuroni and Impossible Calculation brute force, combinatorics, math, number theory	1600	x14172
1301C	Ayoub's function binary search, combinatorics, greedy, math, strings	1700	x9255
1299D	Around the World bitmasks, combinatorics, dfs and similar, dp, graphs, graphs, math, trees	3000	x424
1295F	Good Contest combinatorics, dp, probabilities	2700	x1174
1293B	JOE is on TV! combinatorics, greedy, math	1000	x21096
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	x2028
1288C	Two Arrays combinatorics, dp	1600	x12608
1285F	Classical? binary search, combinatorics, number theory	2900	x1097
1284E	New Year and Castle Construction combinatorics, geometry, math, sortings	2500	x1289
1284C	New Year and Permutation combinatorics, math	1600	x7946
1284B	New Year and Ascent Sequence binary search, combinatorics, data structures, dp, implementation, sortings	1400	x10784
1280F	Intergalactic Sliding Puzzle combinatorics, constructive algorithms, math	3400	x59
1279E	New Year Permutations combinatorics, dp	2700	x359
1279D	Santa's Bot combinatorics, math, probabilities	1700	x6154
1278F	Cards combinatorics, dp, math, number theory, probabilities	2600	x1797
1276C	Beautiful Rectangle brute force, combinatorics, constructive algorithms, data structures, greedy, math	2300	x1640
1276B	Two Fairs combinatorics, dfs and similar, dsu, graphs	1900	x4847
1272C	Yet Another Broken Keyboard combinatorics, dp, implementation	1200	x25922
1271E	Common Number binary search, combinatorics, dp, math	2100	x3338
1267K	Key Storage combinatorics, math	2100	x1877
1264D2	Beautiful Bracket Sequence (hard version) combinatorics, probabilities	2900	x878
1264D1	Beautiful Bracket Sequence (easy version) combinatorics, dp, probabilities	2600	x1201
1254E	Send Tree to Charlie combinatorics, dfs and similar, dsu, trees	3300	x263
1251F	Red-White Fence combinatorics, fft	2500	x805
1245F	Daniel and Spring Cleaning bitmasks, brute force, combinatorics, dp	2300	x1806
1239A	Ivan the Fool and the Probability Theory combinatorics, dp, math	1700	x7265
1238D	AB-string binary search, combinatorics, dp, strings	1900	x5912
1237F	Balanced Domino Placements combinatorics, dp	2600	x848
1236B	Alice and the List of Presents combinatorics, math	1500	x10932
1228E	Another Filling the Grid combinatorics, dp, math	2300	x2590
1227F2	Wrong Answer on test 233 (Hard Version) combinatorics, math	2400	x1476
1221G	Graph And Numbers bitmasks, brute force, combinatorics, dp, meet-in-the-middle	2900	x570
1215B	The Number of Products combinatorics, dp, implementation	1400	x12540
1207D	Number Of Permutations combinatorics	1800	x6016
1205E	Expected Value Again combinatorics, strings	3100	x273
1204E	Natasha, Sasha and the Prefix Sums combinatorics, dp, math, number theory	2300	x1632
1202D	Print a 1337-string... combinatorics, constructive algorithms, math, strings	1900	x5051
1197E	Culture Code binary search, combinatorics, data structures, dp, shortest paths, sortings	2300	x1617
1195D2	Submarine in the Rybinsk Sea (hard edition) combinatorics, math, number theory	1800	x4616
1195D1	Submarine in the Rybinsk Sea (easy edition) combinatorics, math, number theory	1500	x7832
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	x728
1185G1	Playlist for Polycarp (easy version) bitmasks, combinatorics, dp	2100	x2811
1181C	Flag brute force, combinatorics, dp, implementation	1900	x3032
1178F1	Short Colorful Strip combinatorics, dfs and similar, dp	2200	x2075
1178C	Tiles combinatorics, greedy, math	1300	x11720
1174E	Ehab and the Expected GCD Problem combinatorics, dp, math, number theory	2500	x1381
1172B	Nauuo and Circle combinatorics, dfs and similar, dp, trees	1900	x3942
1167F	Scalar Queries combinatorics, data structures, math, sortings	2300	x1600
1167E	Range Deleting binary search, combinatorics, data structures, two pointers	2100	x2577
1166A	Silent Classroom combinatorics, greedy	900	x14080
1153F	Serval and Bonus Problem combinatorics, dp, math, probabilities	2600	x766
1151F	Sonya and Informatics combinatorics, dp, matrices, probabilities	2300	x1173
1151E	Number of Components combinatorics, data structures, dp, math	2100	x3271
1140E	Palindrome-less Arrays combinatorics, divide and conquer, dp	2200	x1904
1118F2	Tree Cutting (Hard Version) combinatorics, dfs and similar, dp, trees	2700	x526
1111D	Destroy the Colony combinatorics, dp, math	2600	x942