combinatorics - Problem Set - HFOJ

	ID	Problem Show tags Hide tags	AC / Tried	Difficulty
	2057	P1542E2 Abnormal Permutation Pairs (hard version) combinatorics dp fft math *2700	0 / 0	10
	2055	P1543B Customising the Track combinatorics greedy math *900	0 / 0	3
	2049	P1545B AquaMoon and Chess combinatorics math *1900	0 / 0	6
	2048	P1545C AquaMoon and Permutations 2-sat brute force combinatorics constructive algorithms graph matchings graphs *2800	0 / 0	10
	2027	P1548C The Three Little Pigs combinatorics dp fft math *2500	0 / 0	9
	2013	P1550D Excellent Arrays binary search combinatorics constructive algorithms implementation math sortings two pointers *2300	0 / 0	8
	1992	P1551F Equidistant Vertices brute force combinatorics dfs and similar dp trees *2200	0 / 0	8
	1988	P1552B Running for Gold combinatorics graphs greedy sortings *1500	0 / 0	5
	1987	P1552C Maximize the Intersections combinatorics constructive algorithms geometry greedy sortings *1800	0 / 0	6
	1965	P1553E Permutation Shift brute force combinatorics constructive algorithms dfs and similar dsu graphs math *2100	0 / 0	7
	1957	P1553I Stairs combinatorics divide and conquer dp fft math *3400	0 / 0	10
	1936	P1556F Sports Betting bitmasks combinatorics dp graphs math probabilities *2500	0 / 0	9
	1930	P1557C Moamen and XOR bitmasks combinatorics dp math matrices *1700	0 / 0	5
	1924	P1558D Top-Notch Insertions combinatorics data structures *2600	0 / 0	10
	1916	P1559E Mocha and Stars combinatorics dp fft math number theory *2200	0 / 0	8
	1878	P1567C Carrying Conundrum bitmasks combinatorics dp math *1600	0 / 0	5
	1866	P1569C Jury Meeting combinatorics math *1500	0 / 0	5
	1823	P1574B Combinatorics Homework combinatorics greedy math *1100	0 / 0	3
	1817	P1574E Coloring combinatorics constructive algorithms implementation math *2500	0 / 0	9
	1814	P1574F Occurrences combinatorics dfs and similar dp dsu fft graphs *2700	0 / 0	10
	1764	P1580B Mathematics Curriculum brute force combinatorics dp trees *2600	0 / 0	10
	1760	P1580F Problems for Codeforces combinatorics fft math *3300	0 / 0	10
	1759	P1581A CQXYM Count Permutations combinatorics math number theory *800	0 / 0	3
	1756	P1582B Luntik and Subsequences combinatorics math *900	0 / 0	3
	1730	P1584D Guess the Permutation binary search combinatorics interactive math *2000	0 / 0	7
	1713	P1585F Non-equal Neighbours combinatorics dp math *2400	0 / 0	9
	1709	P1586I Omkar and Mosaic combinatorics constructive algorithms math *3500	0 / 0	10
	1681	P1594E1 Rubik's Cube Coloring (easy version) combinatorics math *1300	0 / 0	4
	1671	P1598D Training Session combinatorics data structures geometry implementation math *1700	0 / 0	5
	1669	P1598E Staircases brute force combinatorics data structures dfs and similar dp implementation math *2100	0 / 0	7
	1660	P1599C Bubble Strike combinatorics math probabilities ternary search *2000	0 / 0	7
	1627	P1603E A Perfect Problem combinatorics dp math *3200	0 / 0	10
	1626	P1603F October 18, 2017 combinatorics dp implementation math *2700	0 / 0	10
	1617	P1605F PalindORme combinatorics dp *2900	0 / 0	10
	1612	P1606E Arena combinatorics dp math *2100	0 / 0	7
	1590	P1608D Dominoes combinatorics fft graphs math number theory *2400	0 / 0	9
	1587	P1608F MEX counting combinatorics dp implementation *3200	0 / 0	10
	1568	P1610D Not Quite Lee combinatorics dp math number theory *2000	0 / 0	7
	1548	P1612G Max Sum Array combinatorics constructive algorithms greedy sortings *2500	0 / 0	9
	1542	P1613F Tree Coloring combinatorics divide and conquer fft *2600	0 / 0	10
	1539	P1614C Divan and bitwise operations bitmasks combinatorics constructive algorithms dp math *1500	0 / 0	5
	1530	P1615F LEGOndary Grandmaster combinatorics dp math *2800	0 / 0	10
	1520	P1616H Keep XOR Low bitmasks combinatorics data structures divide and conquer dp math *3000	0 / 0	10
	1492	P1620G Subsequences Galore bitmasks combinatorics dp *2400	0 / 0	9
	1479	P1622D Shuffle combinatorics math two pointers *2000	0 / 0	7
	1453	P1626F A Random Code Problem combinatorics dp math number theory probabilities *2800	0 / 0	10
	1435	P1628D1 Game on Sum (Easy Version) combinatorics dp games math *2100	0 / 0	7
	1434	P1628D2 Game on Sum (Hard Version) combinatorics dp games math *2400	0 / 0	9
	1416	P1630E Expected Components combinatorics math number theory probabilities *2900	0 / 0	10
	1355	P1641D Two Arrays bitmasks brute force combinatorics greedy hashing math two pointers *2700	0 / 1	10
	1354	P1641E Special Positions combinatorics divide and conquer fft math *3300	0 / 0	10
	1346	P1644E Expand the Path brute force combinatorics data structures implementation math *1900	0 / 0	6
	1345	P1644F Basis combinatorics fft math number theory *2900	0 / 0	10
	1332	P1648A Weird Sum combinatorics data structures geometry math matrices sortings *1400	0 / 0	4
	1330	P1648C Tyler and Strings combinatorics data structures implementation *1900	0 / 0	6
	1313	P1651E Sum of Matchings brute force combinatorics constructive algorithms dfs and similar graph matchings greedy math *2600	0 / 0	10
	1304	P1654H Three Minimums combinatorics constructive algorithms divide and conquer dp fft math *3500	0 / 0	10
	1290	P1657E Star MST combinatorics dp graph matchings math *2200	0 / 0	8
	1287	P1658B Marin and Anti-coprime Permutation combinatorics math number theory *800	0 / 0	3
	1249	P1662N Drone Photo combinatorics math sortings	0 / 0	(None)
	1244	P1663D Is it rated - 3 *special problem combinatorics dp math	0 / 0	(None)
	1229	P1666F Fancy Stack combinatorics dp implementation *2200	0 / 0	8
	1218	P1667E Centroid Probabilities combinatorics dp fft math *3000	0 / 0	10
	1201	P1670F Jee, You See? bitmasks combinatorics dp *2400	0 / 0	9
	1196	P1671E Preorder combinatorics divide and conquer dp dsu hashing sortings trees *2100	0 / 0	7
	1195	P1671F Permutation Counting brute force combinatorics dp fft math *2700	0 / 0	10
	1181	P1673D Lost Arithmetic Progression combinatorics math number theory *1900	0 / 0	6
	1180	P1673E Power or XOR? bitmasks combinatorics math number theory *2500	0 / 0	9
	1177	P1674B Dictionary combinatorics math *800	0 / 0	3
	1176	P1674C Infinite Replacement combinatorics implementation strings *1000	0 / 0	3
	1142	P1679E Typical Party in Dorm bitmasks combinatorics dp strings *2400	0 / 0	9
	1088	P1687E Become Big For Me combinatorics constructive algorithms greedy math number theory *3500	0 / 0	10
	1056	P1691F K-Set Tree combinatorics dfs and similar dp math trees *2500	0 / 0	9
	1021	P1696E Placing Jinas combinatorics math *2000	0 / 0	7
	1016	P1696H Maximum Product? brute force combinatorics dp greedy implementation math two pointers *3500	0 / 0	10
	1005	P1697E Coloring brute force combinatorics constructive algorithms dp geometry graphs greedy implementation math *2400	0 / 0	9
	993	P1698E PermutationForces II brute force combinatorics greedy sortings trees two pointers *2300	0 / 0	8
	984	P1699C The Third Problem combinatorics constructive algorithms math *1700	0 / 0	5
	970	P1701F Points combinatorics data structures implementation math matrices *2500	0 / 0	9
	947	P1704H1 Game of AI (easy version) combinatorics constructive algorithms dp fft math *3200	0 / 0	10
	946	P1704H2 Game of AI (hard version) combinatorics fft math *3500	0 / 0	10
	942	P1705D Mark and Lightbulbs combinatorics constructive algorithms greedy math sortings *1800	0 / 0	6
	941	P1705E Mark and Professor Koro binary search bitmasks brute force combinatorics data structures greedy *2300	0 / 0	8
	930	P1707D Partial Virtual Trees combinatorics dfs and similar dp math trees *3000	0 / 0	10
	908	P1712E1 LCM Sum (easy version) binary search brute force combinatorics math number theory two pointers *2300	0 / 0	8
	900	P1713F Lost Array bitmasks combinatorics constructive algorithms dp math *2900	0 / 0	10
	890	P1715C Monoblock combinatorics data structures implementation math *1700	0 / 0	5
	881	P1716F Bags with Balls combinatorics dp math number theory *2500	0 / 0	9
	877	P1717D Madoka and The Corruption Scheme combinatorics constructive algorithms greedy math *1900	0 / 0	6
	843	P1725C Circular Mirror binary search combinatorics geometry math two pointers *2000	0 / 0	7
	841	P1725E Electrical Efficiency combinatorics data structures dp math number theory trees *2500	0 / 0	9
	837	P1725I Imitating the Key Tree combinatorics dsu trees *2800	0 / 0	10
	828	P1726E Almost Perfect combinatorics fft math *2400	0 / 0	9
	826	P1726G A Certain Magical Party combinatorics data structures greedy sortings *3300	0 / 0	10
	818	P1728G Illumination binary search bitmasks brute force combinatorics dp math two pointers *2700	0 / 0	10
	811	P1729G Cut Substrings combinatorics dp hashing strings two pointers *2100	0 / 0	7
	806	P1730E Maximums and Minimums combinatorics data structures divide and conquer number theory *2700	0 / 0	10
	799	P1731F Function Sum brute force combinatorics dp fft math *2500	0 / 0	9
	798	P1732A Bestie brute force combinatorics constructive algorithms implementation math number theory *1000	0 / 0	3
	776	P1735D Meta-set brute force combinatorics data structures hashing math *1700	0 / 0	5

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