Problem Set - HFOJ

	ID	Problem Show tags Hide tags	AC / Tried	Difficulty
	1923	P1558E Down Below binary search dfs and similar graphs greedy meet-in-the-middle shortest paths *3000	0 / 0	10
	1922	P1558F Strange Sort data structures sortings *3300	0 / 0	10
	1921	P1559A Mocha and Math bitmasks constructive algorithms math *900	0 / 0	3
	1920	P1559B Mocha and Red and Blue dp greedy *900	0 / 0	3
	1919	P1559C Mocha and Hiking constructive algorithms graphs *1200	0 / 0	4
	1918	P1559D1 Mocha and Diana (Easy Version) brute force constructive algorithms dsu graphs greedy trees *1400	0 / 0	4
	1917	P1559D2 Mocha and Diana (Hard Version) brute force constructive algorithms dfs and similar dsu graphs greedy trees two pointers *2500	0 / 0	9
	1916	P1559E Mocha and Stars combinatorics dp fft math number theory *2200	0 / 0	8
	1915	P1560A Dislike of Threes implementation *800	0 / 0	3
	1913	P1560B Who's Opposite? math *800	0 / 0	3
	1911	P1560C Infinity Table implementation math *800	0 / 0	3
	1910	P1560D Make a Power of Two greedy math strings *1300	0 / 0	4
	1907	P1560E Polycarp and String Transformation binary search implementation sortings strings *1800	0 / 0	6
	1906	P1560F1 Nearest Beautiful Number (easy version) binary search bitmasks brute force constructive algorithms dfs and similar greedy *1900	0 / 0	6
	1905	P1560F2 Nearest Beautiful Number (hard version) bitmasks brute force constructive algorithms dfs and similar dp greedy *2100	0 / 0	7
	1904	P1561A Simply Strange Sort brute force implementation sortings *800	0 / 0	3
	1903	P1561C Deep Down Below binary search greedy sortings *1300	0 / 0	4
	1902	P1561D1 Up the Strip (simplified version) brute force data structures dp math number theory *1700	0 / 0	5
	1901	P1562A The Miracle and the Sleeper greedy math *800	0 / 0	3
	1900	P1562B Scenes From a Memory brute force constructive algorithms implementation math number theory *1000	0 / 0	3
	1899	P1562C Rings constructive algorithms math *1500	0 / 0	5
	1898	P1562D1 Two Hundred Twenty One (easy version) data structures dp math *1700	0 / 0	5
	1897	P1562D2 Two Hundred Twenty One (hard version) data structures math *2200	0 / 0	8
	1896	P1562E Rescue Niwen! dp greedy string suffix structures strings *2500	0 / 0	9
	1895	P1562F Tubular Bells interactive math number theory probabilities *2900	0 / 0	10
	1894	P1566A Median Maximization binary search greedy math *800	0 / 0	3
	1893	P1566B MIN-MEX Cut bitmasks constructive algorithms dp greedy *800	0 / 0	3
	1892	P1566C MAX-MEX Cut bitmasks constructive algorithms dp greedy *1000	0 / 0	3
	1891	P1566D1 Seating Arrangements (easy version) data structures greedy sortings *1100	0 / 0	3
	1890	P1566D2 Seating Arrangements (hard version) data structures greedy implementation sortings two pointers *1600	0 / 0	5
	1889	P1566E Buds Re-hanging constructive algorithms dfs and similar dp greedy trees *2000	0 / 0	7
	1887	P1566F Points Movement data structures dp greedy implementation sortings *2600	0 / 0	10
	1886	P1566G Four Vertices constructive algorithms data structures graphs greedy implementation shortest paths *3100	0 / 0	10
	1883	P1566H Xor-quiz constructive algorithms dp interactive math number theory *3200	0 / 0	10
	1881	P1567A Domino Disaster implementation strings *800	0 / 0	3
	1880	P1567B MEXor Mixup bitmasks greedy *1000	0 / 0	3
	1878	P1567C Carrying Conundrum bitmasks combinatorics dp math *1600	0 / 0	5
	1875	P1567D Expression Evaluation Error constructive algorithms greedy implementation math *2000	0 / 0	7
	1874	P1567E Non-Decreasing Dilemma data structures divide and conquer math *2200	0 / 0	8
	1871	P1567F One-Four Overload 2-sat constructive algorithms dfs and similar dsu graphs implementation *2700	0 / 0	10
	1869	P1569A Balanced Substring implementation *800	0 / 0	3
	1868	P1569B Chess Tournament constructive algorithms *1000	0 / 0	3
	1866	P1569C Jury Meeting combinatorics math *1500	0 / 0	5
	1863	P1569D Inconvenient Pairs binary search data structures implementation sortings two pointers *1900	0 / 0	6
	1861	P1569E Playoff Restoration bitmasks brute force hashing implementation meet-in-the-middle *2600	0 / 0	10
	1859	P1569F Palindromic Hamiltonian Path brute force dfs and similar dp graphs hashing *3000	0 / 0	10
	1857	P1571A Sequence of Comparisons special problem 800	0 / 0	3
	1856	P1571B Epic Novel special problem math 1300	0 / 0	4
	1854	P1571C Rhyme special problem implementation 1800	0 / 0	6
	1852	P1571D Sweepstake special problem brute force constructive algorithms implementation math 1800	0 / 0	6
	1850	P1571E Fix the String special problem bitmasks dp greedy 1700	0 / 0	5
	1848	P1571F Kotlinforces special problem constructive algorithms dp 2000	0 / 0	7
	1845	P1571G A Battle Against a Dragon special problem data structures dp 2500	0 / 0	9
	1843	P1571H Laser Beams special problem geometry probabilities 2900	0 / 0	10
	1841	P1571I Physical Examination special problem binary search data structures 3200	0 / 0	10
	1839	P1571J Two Railroads special problem 3000	0 / 0	10
	1838	P1572A Book binary search brute force data structures dp graphs implementation sortings *1800	0 / 0	6
	1837	P1572B Xor of 3 brute force constructive algorithms greedy two pointers *2500	0 / 0	9
	1836	P1572C Paint dp greedy *2700	0 / 0	10
	1835	P1572D Bridge Club flows graph matchings graphs greedy *2800	0 / 0	10
	1833	P1572E Polygon binary search dp geometry *3000	0 / 0	10
	1830	P1572F Stations data structures *3400	0 / 0	10
	1829	P1573A Countdown greedy *800	0 / 0	3
	1827	P1573B Swaps greedy math sortings *1400	0 / 0	4
	1825	P1574A Regular Bracket Sequences constructive algorithms *800	0 / 0	3
	1823	P1574B Combinatorics Homework combinatorics greedy math *1100	0 / 0	3
	1821	P1574C Slay the Dragon binary search greedy sortings ternary search *1300	0 / 0	4
	1818	P1574D The Strongest Build binary search brute force data structures dfs and similar graphs greedy hashing implementation *2000	0 / 0	7
	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
	1813	P1575A Another Sorting Problem data structures sortings strings *1100	0 / 0	3
	1810	P1575B Building an Amusement Park binary search geometry *2300	0 / 0	8
	1808	P1575C Cyclic Sum data structures fft number theory *3000	0 / 0	10
	1806	P1575D Divisible by Twenty-Five brute force dfs and similar dp *1800	0 / 0	6
	1805	P1575E Eye-Pleasing City Park Tour data structures trees *2600	0 / 0	10
	1803	P1575F Finding Expected Value math *2900	0 / 0	10
	1802	P1575G GCD Festival math number theory *2200	0 / 0	8
	1801	P1575H Holiday Wall Ornaments dp strings *2200	0 / 0	8
	1800	P1575I Illusions of the Desert data structures trees *2300	0 / 0	8
	1799	P1575J Jeopardy of Dropped Balls binary search brute force dsu implementation *1500	0 / 0	5
	1798	P1575K Knitting Batik implementation math *2200	0 / 0	8
	1797	P1575L Longest Array Deconstruction data structures divide and conquer dp sortings *2100	0 / 0	7
	1796	P1575M Managing Telephone Poles data structures geometry *2400	0 / 0	9
	1795	P1576A Communication Routing Challenge *special problem	0 / 0	(None)
	1794	P1578A Anti-Tetris constructive algorithms graphs shortest paths *2800	0 / 0	10
	1793	P1578B Building Forest Trails data structures dsu *2800	0 / 0	10
	1792	P1578C Cactus Lady and her Cing *3500	0 / 0	10
	1790	P1578D Dragon Curve *3200	0 / 0	10
	1788	P1578E Easy Scheduling implementation math *1200	0 / 0	4
	1787	P1578F Framing Pictures geometry *2900	0 / 0	10
	1785	P1578G Game of Chance math probabilities *3500	0 / 0	10
	1784	P1578H Higher Order Functions implementation strings *1700	0 / 0	5
	1783	P1578I Interactive Rays geometry interactive *3300	0 / 0	10
	1782	P1578J Just Kingdom brute force data structures dfs and similar *3100	0 / 0	10
	1779	P1578K Kingdom of Islands brute force graphs implementation *2800	0 / 0	10
	1778	P1578L Labyrinth binary search dsu greedy *2400	0 / 0	9
	1776	P1578M The Mind constructive algorithms interactive probabilities *2700	0 / 0	10
	1773	P1579A Casimir's String Solitaire math strings *800	0 / 0	3
	1772	P1579B Shifting Sort implementation sortings *1100	0 / 0	3
	1771	P1579C Ticks greedy implementation *1500	0 / 0	5

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