combinatorics - Problem Set - HFOJ

	ID	Problem Show tags Hide tags	AC / Tried	Difficulty
	10279	P1916H1 Matrix Rank (Easy Version) brute force combinatorics dp math matrices *2700	0 / 0	10
	10278	P1916H2 Matrix Rank (Hard Version) combinatorics dp math matrices string suffix structures *2700	0 / 0	10
	10223	P1917B Erase First or Second Letter brute force combinatorics data structures dp strings *1100	0 / 0	3
	10221	P1917D Yet Another Inversions Problem combinatorics data structures divide and conquer math *2300	0 / 0	8
	10273	P1919E Counting Prefixes combinatorics constructive algorithms dp implementation math *2600	0 / 0	10
	10264	P1920E Counting Binary Strings combinatorics dp math *2100	0 / 0	7
	10253	P1922B Forming Triangles combinatorics constructive algorithms math sortings *1200	0 / 0	4
	10337	P1924D Balanced Subsequences combinatorics dp math *2700	0 / 0	10
	10336	P1924E Paper Cutting Again combinatorics probabilities *3100	0 / 0	10
	10332	P1925D Good Trip combinatorics dp math probabilities *1900	0 / 0	6
	10319	P1928F Digital Patterns brute force combinatorics data structures implementation math	0 / 0	(None)
	10436	P1929D Sasha and a Walk in the City combinatorics dp math trees *1900	0 / 0	6
	10434	P1929F Sasha and the Wedding Binary Search Tree brute force combinatorics data structures dfs and similar math trees *2300	0 / 0	8
	10428	P1930E 2..3...4... combinatorics dp math *2400	0 / 0	9
	10424	P1930I Counting Is Fun combinatorics *3500	0 / 0	10
	10420	P1931D Divisible Pairs combinatorics math number theory *1300	0 / 0	4
	10418	P1931F Chat Screenshots combinatorics dfs and similar graphs *1700	0 / 0	5
	10417	P1931G One-Dimensional Puzzle combinatorics math number theory *2000	0 / 0	7
	10403	P1933G Turtle Magic: Royal Turtle Shell Pattern bitmasks brute force combinatorics constructive algorithms dfs and similar math *2300	0 / 0	8
	10393	P1935D Exam in MAC binary search combinatorics implementation math *1800	0 / 0	6
	10525	P1942E Farm Game combinatorics games	0 / 0	(None)
	10523	P1942G Bessie and Cards combinatorics dp math	0 / 0	(None)
	10471	P1943D1 Counting Is Fun (Easy Version) brute force combinatorics dp math *2400	0 / 0	9
	10470	P1943D2 Counting Is Fun (Hard Version) combinatorics dp *2800	0 / 0	10
	10452	P1946E Girl Permutation combinatorics dp math number theory *2200	0 / 0	8
	10349	P1948F Rare Coins combinatorics math probabilities	0 / 0	(None)
	10508	P1951G Clacking Balls combinatorics math probabilities	0 / 0	(None)
	10501	P1952E Sweep Line combinatorics games math	0 / 0	(None)
	10492	P1954D Colored Balls combinatorics dp math sortings	0 / 0	(None)
	10490	P1954F Unique Strings combinatorics dp math	0 / 0	(None)
	10619	P1967C Fenwick Tree bitmasks brute force combinatorics data structures dp math trees *2300	0 / 0	8
	10617	P1967E1 Again Counting Arrays (Easy Version) combinatorics dp fft math *3100	0 / 0	10
	10616	P1967E2 Again Counting Arrays (Hard Version) combinatorics dp math *3500	0 / 0	10
	10561	P1974C Beautiful Triple Pairs combinatorics data structures *1400	0 / 0	4
	10551	P1975F Set bitmasks brute force combinatorics dfs and similar divide and conquer dp math *2600	0 / 0	10
	10544	P1976D Invertible Bracket Sequences binary search combinatorics data structures divide and conquer implementation two pointers	0 / 0	(None)
	10543	P1976E Splittable Permutations combinatorics data structures dfs and similar greedy math trees	0 / 0	(None)
	10690	P1979C Earning on Bets binary search combinatorics constructive algorithms number theory *1200	0 / 0	4
	10674	P1982E Number of k-good subarrays bitmasks brute force combinatorics divide and conquer dp math meet-in-the-middle *2300	0 / 0	8
	10669	P1984C2 Magnitude (Hard Version) combinatorics dp greedy math *1700	0 / 0	5
	10664	P1984H Tower Capturing combinatorics dp geometry *3300	0 / 0	10
	10659	P1985E Secret Box brute force combinatorics math *1200	0 / 0	4
	10657	P1985G D-Function combinatorics math number theory *1600	0 / 0	5
	10648	P1986G1 Permutation Problem (Simple Version) binary search brute force combinatorics data structures math number theory *2200	0 / 0	8
	10750	P1988F Heartbeat combinatorics dp fft math *3000	0 / 0	10
	10632	P1989E Distance to Different combinatorics dp math *2300	0 / 0	8
	10736	P1991G Grid Reset combinatorics constructive algorithms greedy implementation	0 / 0	(None)
	10727	P1992G Ultra-Meow combinatorics dp math *2000	0 / 0	7
	10719	P1994H Fortnite combinatorics constructive algorithms games greedy hashing interactive math number theory strings *3500	0 / 0	10
	10708	P1996D Fun binary search brute force combinatorics math number theory	0 / 0	(None)
	10707	P1996E Decode combinatorics implementation math	0 / 0	(None)

Pick a problem randomly based on the current filter.