Problem Set - HFOJ

	ID	Problem Show tags Hide tags	AC / Tried	Difficulty
	2067	P1540D Inverse Inversions binary search brute force data structures *3200	0 / 0	10
	2066	P1540E Tasty Dishes math matrices *3500	0 / 0	10
	2065	P1541A Pretty Permutations constructive algorithms greedy implementation *800	0 / 0	3
	2064	P1541B Pleasant Pairs brute force implementation math number theory *1200	0 / 0	4
	2063	P1542A Odd Set math *800	0 / 0	3
	2062	P1542B Plus and Multiply constructive algorithms math number theory *1500	0 / 0	5
	2061	P1542C Strange Function math number theory *1600	0 / 0	5
	2059	P1542D Priority Queue combinatorics dp implementation math ternary search *2200	0 / 0	8
	2058	P1542E1 Abnormal Permutation Pairs (easy version) combinatorics dp fft math *2400	0 / 0	9
	2057	P1542E2 Abnormal Permutation Pairs (hard version) combinatorics dp fft math *2700	0 / 0	10
	2056	P1543A Exciting Bets greedy math number theory *900	0 / 0	3
	2055	P1543B Customising the Track combinatorics greedy math *900	0 / 0	3
	2054	P1543C Need for Pink Slips bitmasks brute force dfs and similar implementation math probabilities *1900	0 / 0	6
	2053	P1543D1 RPD and Rap Sheet (Easy Version) bitmasks constructive algorithms interactive math *1700	0 / 0	5
	2052	P1543D2 RPD and Rap Sheet (Hard Version) brute force constructive algorithms interactive math *2200	0 / 0	8
	2051	P1543E The Final Pursuit bitmasks constructive algorithms divide and conquer graphs greedy math *2700	0 / 0	10
	2050	P1545A AquaMoon and Strange Sort sortings *1500	0 / 0	5
	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
	2047	P1545D AquaMoon and Wrong Coordinate constructive algorithms interactive math *3000	0 / 0	10
	2046	P1545E1 AquaMoon and Time Stop (easy version) data structures dp *3500	0 / 0	10
	2045	P1545E2 AquaMoon and Time Stop (hard version) data structures dp *3500	0 / 0	10
	2044	P1545F AquaMoon and Potatoes brute force data structures dp *3500	0 / 0	10
	2043	P1546A AquaMoon and Two Arrays brute force greedy *800	0 / 0	3
	2042	P1546B AquaMoon and Stolen String interactive math *1200	0 / 0	4
	2041	P1547A Shortest Path with Obstacle implementation math *800	0 / 0	3
	2040	P1547B Alphabetical Strings greedy implementation strings *800	0 / 0	3
	2039	P1547C Pair Programming greedy two pointers *1100	0 / 0	3
	2038	P1547D Co-growing Sequence bitmasks constructive algorithms greedy *1300	0 / 0	4
	2036	P1547E Air Conditioners data structures dp implementation shortest paths sortings two pointers *1500	0 / 0	5
	2035	P1547F Array Stabilization (GCD version) binary search brute force data structures divide and conquer number theory two pointers *1900	0 / 0	6
	2033	P1547G How Many Paths? dfs and similar dp graphs trees *2100	0 / 0	7
	2030	P1548A Web of Lies brute force graphs greedy *1400	0 / 0	4
	2028	P1548B Integers Have Friends binary search data structures divide and conquer math number theory two pointers *1800	0 / 0	6
	2027	P1548C The Three Little Pigs combinatorics dp fft math *2500	0 / 0	9
	2026	P1548D1 Gregor and the Odd Cows (Easy) bitmasks geometry math number theory *2300	0 / 0	8
	2025	P1548D2 Gregor and the Odd Cows (Hard) brute force geometry math number theory *3300	0 / 0	10
	2024	P1548E Gregor and the Two Painters data structures divide and conquer graphs greedy math *3400	0 / 0	10
	2022	P1549A Gregor and Cryptography math number theory *800	0 / 0	3
	2020	P1549B Gregor and the Pawn Game dfs and similar dp flows graph matchings graphs greedy implementation *800	0 / 0	3
	2018	P1550A Find The Array greedy math *800	0 / 0	3
	2016	P1550B Maximum Cost Deletion greedy math *1000	0 / 0	3
	2015	P1550C Manhattan Subarrays brute force geometry greedy implementation *1700	0 / 0	5
	2013	P1550D Excellent Arrays binary search combinatorics constructive algorithms implementation math sortings two pointers *2300	0 / 0	8
	2011	P1550E Stringforces binary search bitmasks brute force dp strings two pointers *2500	0 / 0	9
	2009	P1550F Jumping Around binary search data structures divide and conquer dp dsu graphs shortest paths *2700	0 / 0	10
	2007	P1551A Polycarp and Coins greedy math *800	0 / 0	3
	2004	P1551B1 Wonderful Coloring - 1 greedy strings *800	0 / 0	3
	2002	P1551B2 Wonderful Coloring - 2 binary search constructive algorithms data structures greedy *1400	0 / 0	4
	2000	P1551C Interesting Story greedy sortings strings *1500	0 / 0	5
	1999	P1551D1 Domino (easy version) constructive algorithms math *1700	0 / 0	5
	1997	P1551D2 Domino (hard version) constructive algorithms implementation math *2100	0 / 0	7
	1995	P1551E Fixed Points binary search brute force dp *2000	0 / 0	7
	1992	P1551F Equidistant Vertices brute force combinatorics dfs and similar dp trees *2200	0 / 0	8
	1991	P1552A Subsequence Permutation sortings strings *800	0 / 0	3
	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
	1984	P1552D Array Differentiation bitmasks brute force constructive algorithms dfs and similar dp graphs math *1800	0 / 0	6
	1983	P1552E Colors and Intervals constructive algorithms data structures greedy sortings *2300	0 / 0	8
	1980	P1552F Telepanting binary search data structures dp sortings *2200	0 / 0	8
	1978	P1552G A Serious Referee bitmasks brute force dfs and similar sortings *3000	0 / 0	10
	1977	P1552H Guess the Perimeter binary search interactive number theory *3300	0 / 0	10
	1975	P1552I Organizing a Music Festival dfs and similar math *3400	0 / 0	10
	1973	P1553A Digits Sum math number theory *800	0 / 0	3
	1971	P1553B Reverse String brute force dp hashing implementation strings *1300	0 / 0	4
	1969	P1553C Penalty bitmasks brute force dp greedy *1200	0 / 0	4
	1967	P1553D Backspace dp greedy strings two pointers *1500	0 / 0	5
	1965	P1553E Permutation Shift brute force combinatorics constructive algorithms dfs and similar dsu graphs math *2100	0 / 0	7
	1964	P1553F Pairwise Modulo data structures math *2300	0 / 0	8
	1962	P1553G Common Divisor Graph brute force constructive algorithms dsu graphs hashing math number theory *2700	0 / 0	10
	1959	P1553H XOR and Distance bitmasks divide and conquer trees *2900	0 / 0	10
	1957	P1553I Stairs combinatorics divide and conquer dp fft math *3400	0 / 0	10
	1955	P1554A Cherry greedy *800	0 / 0	3
	1953	P1554B Cobb bitmasks brute force greedy math *1700	0 / 0	5
	1951	P1554C Mikasa binary search bitmasks greedy implementation *1800	0 / 0	6
	1950	P1554D Diane constructive algorithms greedy strings *1800	0 / 0	6
	1949	P1554E You dfs and similar dp math number theory *2600	0 / 0	10
	1948	P1555A PizzaForces brute force math *900	0 / 0	3
	1947	P1555B Two Tables brute force *1300	0 / 0	4
	1946	P1555C Coin Rows brute force constructive algorithms dp implementation *1300	0 / 0	4
	1944	P1555D Say No to Palindromes brute force constructive algorithms dp strings *1600	0 / 0	5
	1943	P1555E Boring Segments data structures sortings trees two pointers *2100	0 / 0	7
	1942	P1555F Good Graph data structures dsu graphs trees *2700	0 / 0	10
	1941	P1556A A Variety of Operations math *800	0 / 0	3
	1940	P1556B Take Your Places! implementation *1300	0 / 0	4
	1939	P1556C Compressed Bracket Sequence brute force implementation *1800	0 / 0	6
	1938	P1556D Take a Guess bitmasks constructive algorithms interactive math *1800	0 / 0	6
	1937	P1556E Equilibrium data structures dp greedy *2200	0 / 0	8
	1936	P1556F Sports Betting bitmasks combinatorics dp graphs math probabilities *2500	0 / 0	9
	1935	P1556G Gates to Another World bitmasks data structures dsu two pointers *3300	0 / 0	10
	1934	P1556H DIY Tree graphs greedy math probabilities *3300	0 / 0	10
	1933	P1557A Ezzat and Two Subsequences brute force math sortings *800	0 / 0	3
	1932	P1557B Moamen and k-subarrays greedy sortings *1100	0 / 0	3
	1930	P1557C Moamen and XOR bitmasks combinatorics dp math matrices *1700	0 / 0	5
	1929	P1557D Ezzat and Grid data structures dp greedy *2200	0 / 0	8
	1928	P1557E Assiut Chess brute force constructive algorithms interactive *2800	0 / 0	10
	1927	P1558A Charmed by the Game brute force math *1300	0 / 0	4
	1926	P1558B Up the Strip brute force dp math number theory two pointers *1900	0 / 0	6
	1925	P1558C Bottom-Tier Reversals constructive algorithms greedy *2000	0 / 0	7
	1924	P1558D Top-Notch Insertions combinatorics data structures *2600	0 / 0	10

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