Problemset - Codeforces

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Codeforces Round (Div. 2)
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combinatorics

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Problems

#	Name
762F	Tree nesting combinatorics, graphs, trees	2800	x376
757E	Bash Plays with Functions brute force, combinatorics, dp, number theory	2500	x1326
756E	Byteland coins combinatorics, dp, math	3200	x168
756D	Bacterial Melee brute force, combinatorics, dp, string suffix structures	2400	x1001
755G	PolandBall and Many Other Balls combinatorics, divide and conquer, dp, fft, math, number theory	3200	x911
750G	New Year and Binary Tree Paths bitmasks, brute force, combinatorics, dp	3200	x448
747F	Igor and Interesting Numbers brute force, combinatorics, dp, math	2500	x418
735C	Tennis Championship combinatorics, constructive algorithms, greedy, math	1600	x7509
724F	Uniformly Branched Trees combinatorics, dp, trees	2700	x401
722E	Research Rover combinatorics, dp	2900	x869
717A	Festival Organization combinatorics, math, number theory	2900	x352
715E	Complete the Permutations combinatorics, fft, graphs, math	3400	x356
712D	Memory and Scores combinatorics, dp, math	2200	x1833
711D	Directed Roads combinatorics, dfs and similar, graphs, math	1900	x4456
698F	Coprime Permutation combinatorics, number theory	3000	x436
696C	PLEASE combinatorics, dp, implementation, math, matrices	2000	x2084
690D2	The Wall (medium) combinatorics	1800	x1246
689E	Mike and Geometry Problem combinatorics, data structures, dp, geometry, implementation	2000	x1922
689C	Mike and Chocolate Thieves binary search, combinatorics, math	1700	x5315
685A	Robbers' watch brute force, combinatorics, dp, math	1700	x4227
677C	Vanya and Label bitmasks, combinatorics, implementation, strings	1500	x6407
666C	Codeword combinatorics, strings	2500	x785
660E	Different Subsets For All Tuples combinatorics, math	2300	x1501
659G	Fence Divercity combinatorics, dp, number theory	2300	x1183
653G	Move by Prime combinatorics, math, number theory	3100	x547
652C	Foe Pairs combinatorics, sortings, two pointers	1800	x3220
645F	Cowslip Collections combinatorics, math, number theory	2500	x787
630I	Parking Lot combinatorics, math	1700	x6710
630H	Benches combinatorics, math	1400	x4943
630G	Challenge Pennants combinatorics, math	1600	x2734
630F	Selection of Personnel combinatorics, math	1300	x6801
630C	Lucky Numbers combinatorics, math	1100	x21832
629E	Famil Door and Roads combinatorics, data structures, dfs and similar, dp, probabilities, trees	2300	x1001
629A	Far Relative’s Birthday Cake brute force, combinatorics, constructive algorithms, implementation	800	x13368
626D	Jerry's Protest brute force, combinatorics, dp, probabilities	1800	x2751
623E	Transforming Sequence combinatorics, dp, fft, math	3300	x548
621C	Wet Shark and Flowers combinatorics, math, number theory, probabilities	1700	x5455
621B	Wet Shark and Bishops combinatorics, implementation	1300	x10971
617B	Chocolate combinatorics	1300	x17865
612E	Square Root of Permutation combinatorics, constructive algorithms, dfs and similar, graphs, math	2200	x1684
610A	Pasha and Stick combinatorics, math	1000	x23131
608B	Hamming Distance Sum combinatorics, strings	1500	x6812
603B	Moodular Arithmetic combinatorics, dfs and similar, dsu, math, number theory	1800	x2576
596C	Wilbur and Points combinatorics, greedy, sortings	1700	x2255
585E	Present for Vitalik the Philatelist combinatorics, math, number theory	2900	x1105
584B	Kolya and Tanya combinatorics	1500	x11945
577B	Modulo Sum combinatorics, data structures, dp, two pointers	1900	x12135
575H	Bots combinatorics, dp, math, number theory	1800	x1679
571A	Lengthening Sticks combinatorics, implementation, math	2100	x2324
570E	Pig and Palindromes combinatorics, dp	2300	x1889
568B	Symmetric and Transitive combinatorics, dp, math	1900	x2240
559D	Randomizer combinatorics, geometry, probabilities	2800	x437
559C	Gerald and Giant Chess combinatorics, dp, math, number theory	2200	x6467
557D	Vitaly and Cycle combinatorics, dfs and similar, graphs, math	2000	x2201
553B	Kyoya and Permutation binary search, combinatorics, constructive algorithms, greedy, implementation, math	1900	x2116
553A	Kyoya and Colored Balls combinatorics, dp, math	1500	x8644
552D	Vanya and Triangles brute force, combinatorics, data structures, geometry, math, sortings	1900	x4479
551D	GukiZ and Binary Operations combinatorics, implementation, math, matrices, number theory	2100	x1963
547C	Mike and Foam bitmasks, combinatorics, dp, math, number theory	2300	x2830
535B	Tavas and SaDDas bitmasks, brute force, combinatorics, implementation	1100	x22428
520E	Pluses everywhere combinatorics, dp, math, number theory	2200	x1874
518F	Pasha and Pipe binary search, brute force, combinatorics, dp, implementation	2300	x367
518D	Ilya and Escalator combinatorics, dp, math, probabilities	1700	x6964
506E	Mr. Kitayuta's Gift combinatorics, dp, matrices, strings	3000	x740
501E	Misha and Palindrome Degree binary search, combinatorics, implementation	2500	x914
500D	New Year Santa Network combinatorics, dfs and similar, graphs, trees	1900	x3116
489F	Special Matrices combinatorics, dp	2100	x1667
489D	Unbearable Controversy of Being brute force, combinatorics, dfs and similar, graphs	1700	x6674
482D	Random Function and Tree combinatorics, dp, trees	2700	x531
479E	Riding in a Lift combinatorics, dp	1900	x5120
478B	Random Teams combinatorics, constructive algorithms, greedy, math	1300	x36490
476B	Dreamoon and WiFi bitmasks, brute force, combinatorics, dp, math, probabilities	1300	x30565
466D	Increase Sequence combinatorics, dp	2100	x3183
459C	Pashmak and Buses combinatorics, constructive algorithms, math	1900	x6181
459B	Pashmak and Flowers combinatorics, implementation, sortings	1300	x40227
457D	Bingo! combinatorics, math, probabilities	2700	x279
452C	Magic Trick combinatorics, math, probabilities	2100	x1624
451E	Devu and Flowers bitmasks, combinatorics, number theory	2300	x3599
449D	Jzzhu and Numbers bitmasks, combinatorics, dp	2400	x4406
439E	Devu and Birthday Celebration combinatorics, dp, math	2100	x1568
438E	The Child and Binary Tree combinatorics, divide and conquer, fft, number theory	3100	x1883
431D	Random Task binary search, bitmasks, combinatorics, dp, math	2100	x2314
414C	Mashmokh and Reverse Operation combinatorics, divide and conquer	2100	x2216
414B	Mashmokh and ACM combinatorics, dp, number theory	1400	x22223
407C	Curious Array brute force, combinatorics, implementation, math	2500	x988
403D	Beautiful Pairs of Numbers combinatorics, dp	2300	x1098
401D	Roman and Numbers bitmasks, brute force, combinatorics, dp, number theory	2000	x4154
396D	On Sum of Number of Inversions in Permutations combinatorics, math		x434
396A	On Number of Decompositions into Multipliers combinatorics, math, number theory		x1505
392C	Yet Another Number Sequence combinatorics, math, matrices		x591
383E	Vowels combinatorics, divide and conquer, dp	2700	x3045
382E	Ksenia and Combinatorics combinatorics, dp	2600	x379
380D	Sereja and Cinema combinatorics, math	2500	x462
374B	Inna and Nine combinatorics, greedy	1500	x3318
372E	Drawing Circles is Fun combinatorics, geometry	3000	x172
367E	Sereja and Intervals combinatorics, dp	2700	x1115
364A	Matrix combinatorics, data structures, implementation	1600	x4668
360C	Levko and Strings combinatorics, dp	2500	x1106
356C	Compartments combinatorics, constructive algorithms, greedy, implementation	2100	x1265
353B	Two Heaps combinatorics, constructive algorithms, greedy, implementation, math, sortings	1900	x2282