combinatorics - Problem Set - HFOJ

	ID	Problem Show tags Hide tags	AC / Tried	Difficulty
	9728	P9D How many trees? combinatorics divide and conquer dp *1900	0 / 0	6
	9697	P15E Triangles combinatorics dp *2600	0 / 0	10
	9647	P26C Parquet combinatorics constructive algorithms greedy implementation *2000	0 / 0	7
	9646	P26D Tickets combinatorics math probabilities *2400	0 / 0	9
	9637	P28C Bath Queue combinatorics dp probabilities *2200	0 / 0	8
	9591	P37D Lesson Timetable combinatorics dp math *2300	0 / 0	8
	9566	P40E Number Table combinatorics *2500	0 / 0	9
	9542	P44I Toys brute force combinatorics *2300	0 / 0	8
	9496	P51E Pentagon combinatorics graphs matrices *2400	0 / 0	9
	9493	P52B Right Triangles combinatorics *1600	0 / 0	5
	9469	P57C Array combinatorics math *1900	0 / 0	6
	9301	P91C Ski Base combinatorics dsu graphs *2300	0 / 0	8
	9236	P107B Basketball Team combinatorics dp math probabilities *1600	0 / 0	5
	9220	P111D Petya and Coloring combinatorics dp *2300	0 / 0	8
	9212	P113E Sleeping combinatorics implementation math *2700	0 / 0	10
	9175	P121C Lucky Permutation brute force combinatorics number theory *1900	0 / 0	6
	9168	P123C Brackets combinatorics dp greedy *2300	0 / 0	8
	9164	P124B Permutations brute force combinatorics implementation *1400	0 / 0	4
	9149	P128C Games with Rectangle combinatorics dp *2000	0 / 0	7
	9132	P131C The World is a Theatre combinatorics math *1400	0 / 0	4
	9114	P135E Weak Subsequence combinatorics *3000	0 / 0	10
	9095	P140E New Year Garland combinatorics dp *2600	0 / 0	10
	9074	P145C Lucky Subsequence combinatorics dp math *2100	0 / 0	7
	9073	P145D Lucky Pair combinatorics data structures implementation *2900	0 / 0	10
	9056	P150B Quantity of Strings combinatorics dfs and similar graphs math *1600	0 / 0	5
	9048	P152C Pocket Book combinatorics *1400	0 / 0	4
	9031	P156C Cipher combinatorics dp *2000	0 / 0	7
	9030	P156D Clues combinatorics graphs *2500	0 / 0	9
	8966	P171B Star special problem combinatorics 1300	0 / 4	4
	8938	P176C Playing with Superglue combinatorics constructive algorithms *2000	0 / 0	7
	8798	P201E Thoroughly Bureaucratic Organization binary search combinatorics *2600	0 / 0	10
	8781	P204A Little Elephant and Interval binary search combinatorics dp *1500	0 / 0	5
	8737	P212C Cowboys combinatorics dp math *2100	0 / 0	7
	8733	P213B Numbers combinatorics dp *1900	0 / 0	6
	8723	P215E Periodical Numbers combinatorics dp number theory *2100	0 / 0	7
	8714	P217D Bitonix' Patrol bitmasks brute force combinatorics dfs and similar math *2900	0 / 0	10
	8691	P223C Partial Sums combinatorics math number theory *1900	0 / 0	6
	8667	P229C Triangles combinatorics graphs math *1900	0 / 0	6
	8665	P229E Gifts combinatorics dp math probabilities *2600	0 / 0	10
	8656	P232B Table bitmasks combinatorics dp math *1900	0 / 0	6
	8638	P235E Number Challenge combinatorics dp implementation math number theory *2600	0 / 0	10
	8577	P251A Points on Line binary search combinatorics two pointers *1300	0 / 0	4
	8547	P258B Little Elephant and Elections brute force combinatorics dp *1900	0 / 0	6
	8546	P258C Little Elephant and LCM binary search combinatorics dp math *2000	0 / 0	7
	8489	P272D Dima and Two Sequences combinatorics math sortings *1600	0 / 0	5
	8488	P272E Dima and Horses combinatorics constructive algorithms graphs *2200	0 / 0	8
	8445	P283E Cow Tennis Tournament combinatorics data structures math *2800	0 / 0	10
	8439	P285D Permutation Sum bitmasks combinatorics dp implementation meet-in-the-middle *1900	0 / 0	6
	8438	P285E Positions in Permutations combinatorics dp math *2600	0 / 0	10
	8429	P288B Polo the Penguin and Houses combinatorics *1500	0 / 0	5
	8427	P288D Polo the Penguin and Trees combinatorics dfs and similar trees *2400	0 / 0	9
	8406	P293B Distinct Paths brute force combinatorics *2700	0 / 0	10
	8400	P294C Shaass and Lights combinatorics number theory *1900	0 / 0	6
	8395	P295C Greg and Friends combinatorics dp graphs shortest paths *2100	0 / 0	7
	8394	P295D Greg and Caves combinatorics dp *2400	0 / 0	9
	8391	P296B Yaroslav and Two Strings combinatorics dp *2000	0 / 0	7
	8379	P300C Beautiful Numbers brute force combinatorics *1800	0 / 0	6
	8359	P305D Olya and Graph combinatorics math *2200	0 / 0	8
	8355	P306C White, Black and White Again combinatorics number theory *2100	0 / 0	7
	8304	P319A Malek Dance Club combinatorics math *1600	0 / 0	5
	8291	P322B Ciel and Flowers combinatorics math *1600	0 / 0	5
	8290	P323A Black-and-White Cube combinatorics constructive algorithms *1600	0 / 0	5
	8283	P325E The Red Button combinatorics dfs and similar dsu graphs greedy *2800	0 / 0	10
	8280	P327C Magic Five combinatorics math *1700	0 / 0	5
	8278	P327E Axis Walking bitmasks combinatorics constructive algorithms dp meet-in-the-middle *2300	0 / 0	8
	8235	P336D Vasily the Bear and Beautiful Strings combinatorics math number theory *2100	0 / 0	7
	8234	P336E Vasily the Bear and Painting Square bitmasks combinatorics dp implementation *2700	0 / 0	10
	8219	P340C Tourist Problem combinatorics implementation math *1600	0 / 0	5
	8217	P340E Iahub and Permutations combinatorics math *2000	0 / 0	7
	8175	P351B Jeff and Furik combinatorics dp probabilities *1900	0 / 0	6
	8168	P353B Two Heaps combinatorics constructive algorithms greedy implementation math sortings *1900	0 / 0	6
	8155	P356C Compartments combinatorics constructive algorithms greedy implementation *2100	0 / 0	7
	8138	P360C Levko and Strings combinatorics dp *2500	0 / 0	9
	8123	P364A Matrix combinatorics data structures implementation *1600	0 / 0	5
	8107	P367E Sereja and Intervals combinatorics dp *2700	0 / 0	10
	8085	P372E Drawing Circles is Fun combinatorics geometry *3000	0 / 0	10
	8081	P374B Inna and Nine combinatorics greedy *1500	0 / 0	5
	8053	P380D Sereja and Cinema combinatorics math *2500	0 / 0	9
	8045	P382E Ksenia and Combinatorics combinatorics dp *2600	0 / 0	10
	8040	P383E Vowels combinatorics divide and conquer dp *2700	0 / 0	10
	7997	P392C Yet Another Number Sequence combinatorics math matrices	0 / 0	(None)
	7987	P396A On Number of Decompositions into Multipliers combinatorics math number theory	0 / 0	(None)
	7984	P396D On Sum of Number of Inversions in Permutations combinatorics math	0 / 0	(None)
	7965	P401D Roman and Numbers bitmasks brute force combinatorics dp number theory *2000	0 / 0	7
	7958	P403D Beautiful Pairs of Numbers combinatorics dp *2300	0 / 0	8
	7942	P407C Curious Array brute force combinatorics implementation math *2500	0 / 0	9
	7914	P414B Mashmokh and ACM combinatorics dp number theory *1400	1 / 1	4
	7913	P414C Mashmokh and Reverse Operation combinatorics divide and conquer *2100	0 / 0	7
	7862	P431D Random Task binary search bitmasks combinatorics dp math *2100	0 / 0	7
	7831	P438E The Child and Binary Tree combinatorics divide and conquer fft number theory *3100	0 / 0	10
	7826	P439E Devu and Birthday Celebration combinatorics dp math *2100	0 / 0	7
	7787	P449D Jzzhu and Numbers bitmasks combinatorics dp *2400	0 / 0	9
	7779	P451E Devu and Flowers bitmasks combinatorics number theory *2300	0 / 0	8
	7776	P452C Magic Trick combinatorics math probabilities *2100	0 / 0	7
	7755	P457D Bingo! combinatorics math probabilities *2700	0 / 0	10
	7751	P459B Pashmak and Flowers combinatorics implementation sortings *1300	0 / 0	4
	7750	P459C Pashmak and Buses combinatorics constructive algorithms math *1900	0 / 0	6
	7720	P466D Increase Sequence combinatorics dp *2100	0 / 0	7
	7673	P476B Dreamoon and WiFi bitmasks brute force combinatorics dp math probabilities *1300	0 / 0	4
	7666	P478B Random Teams combinatorics constructive algorithms greedy math *1300	0 / 0	4

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