Problems

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Total results21,054 problems

LogoHard10
Dynamic programming, Bit manipulation +2No attempts yetTime limit1sMemory limit128 MB
Judgeable
String Palindrome QueriesHard10
String, String matching +1No attempts yetTime limit2sMemory limit256 MB
Judgeable
Suneung FractionsHard10
Math, Number theory +2No attempts yetTime limit1sMemory limit1024 MB
Judgeable
RobotsHard10
Implementation, Bit manipulation +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
HyperrectangleHard10
Math, Divide and conquer +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
Natural ParkHard10
Graph, BFS +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
Dungeon 2Hard10
Graph, BFS +2No attempts yetTime limit1sMemory limit256 MB
Judgeable
Shadow CompanionHard10
Simulation, Bit manipulation +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
Delightful (Easy)Hard10
Implementation, Simulation +2No attempts yetTime limit1sMemory limit512 MB
Judgeable
Xorshift64Hard10
Math, Bit manipulation +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
No Description 2Hard10
ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
HQ0-9+-INCOMPUTABLE?!Hard10
String, Simulation +2No attempts yetTime limit1sMemory limit1024 MB
Judgeable
Beautiful AutomataHard10
Graph, Topological sort +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
Mysterious … HostHard10
Combinatorics, Math +2No attempts yetTime limit2sMemory limit256 MB
Judgeable
Fast BridgesHard10
Shortest path, Sorting +2No attempts yetTime limit2sMemory limit1024 MB
Judgeable
Rational ApproximationUnrated
Not classified yetNo attempts yetTime limit1sMemory limit128 MB
Judgeable
ZuUnrated
Not classified yetNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Star Pattern 15Unrated
Not classified yetNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Star Pattern - 16Unrated
Not classified yetNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Printing Stars 20Unrated
Not classified yetNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Star pattern 22Unrated
Not classified yetNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Project Team Vacation ScheduleUnrated
Not classified yetNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Maximum edge cost on a tree pathUnrated
Not classified yetNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Distinct weights on a tree pathUnrated
Not classified yetNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Glory GraphUnrated
Not classified yetNo attempts yetTime limit3sMemory limit512 MB
Judgeable
CardiologyUnrated
Not classified yetNo attempts yetTime limit2sMemory limit2048 MB
Judgeable
Spiral MatrixUnrated
Not classified yetNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Nice ShapeUnrated
Not classified yetNo attempts yetTime limit4sMemory limit512 MB
Judgeable
City DevelopmentUnrated
Not classified yetNo attempts yetTime limit3sMemory limit512 MB
Judgeable
Distributing the TreasureUnrated
Not classified yetNo attempts yetTime limit4sMemory limit1024 MB
Judgeable
PostmanUnrated
Not classified yetNo attempts yetTime limit8sMemory limit256 MB
Judgeable
Amusement ArcadeUnrated
Not classified yetNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
ABBCUnrated
Not classified yetNo attempts yetTime limit3sMemory limit1024 MB
Judgeable
Special PrizeUnrated
Not classified yetNo attempts yetTime limit2sMemory limit1024 MB
Judgeable
Changing CardsUnrated
Not classified yetNo attempts yetTime limit1.5sMemory limit1024 MB
Judgeable
DigestaUnrated
Not classified yetNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Curious ShiftUnrated
Not classified yetNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
KingdomUnrated
Not classified yetNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
AuthorityUnrated
Not classified yetNo attempts yetTime limit2sMemory limit1024 MB
Judgeable
Keep in TouchUnrated
Not classified yetNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Make an XUnrated
Not classified yetNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Make an X (Hard)Unrated
Not classified yetNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Predicting the grassUnrated
Not classified yetNo attempts yetTime limit2sMemory limit1024 MB
Judgeable
String TowerUnrated
Not classified yetNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Two-dimensional arrayUnrated
Not classified yetNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Chocolate and the King GameUnrated
Not classified yetNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Odd/Even StringsUnrated
Not classified yetNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Check ListUnrated
Not classified yetNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
SGA PresidentUnrated
Not classified yetNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
I Love You, YonseiUnrated
Not classified yetNo attempts yetTime limit1.885sMemory limit1024 MB
Judgeable
Interplanetary Study MeetingUnrated
Not classified yetNo attempts yetTime limit2sMemory limit1024 MB
Judgeable
Unbroken Spirit 3Unrated
Not classified yetNo attempts yetTime limit6sMemory limit1024 MB
Judgeable
Vertical CalendarUnrated
Not classified yetNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Alternating AlgorithmUnrated
Not classified yetNo attempts yetTime limit7sMemory limit1024 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
LogoGiven up to five polyomino patch shapes (each a subset of a 3x3 grid, flippable and rotatable) and up to three grid designs up to 55x5, decide if each design can be tiled exactly by non-overlapping patches and find the minimum patch count, or report NIE.	Hard10	Dynamic programmingBit manipulation+2	No attempts yet	1s	128 MB	Judgeable
String Palindrome QueriesMaintain a lowercase string under block moves, reversals, and single-character insertions, answering after each change whether a given substring reads the same forwards and backwards.	Hard10	StringString matching+1	No attempts yet	2s	256 MB	Judgeable
Suneung FractionsGiven x in [A,B] and y in [C,D] up to 1e12, count pairs where the reduced numerator and denominator sum to at most 999.	Hard10	MathNumber theory+2	No attempts yet	1s	1024 MB	Judgeable
RobotsDesign two robots' instruction tables so they classify a binary string as fine or coarse from its middle third's A and B counts, using four-bit memories, exact-then-wildcard dispatch, and 1000n steps.	Hard10	ImplementationBit manipulation+2	No attempts yet	2s	512 MB	Judgeable
HyperrectangleCompute d!V for the volume of a box with side lengths li where sum xi <= s via characteristic polynomials and Lenstra inclusion of capped orthants.	Hard10	MathDivide and conquer+2	No attempts yet	2s	512 MB	Judgeable
Natural ParkReconstruct the exact edge set of a sparse connected graph with degree at most 7 using at most 45,000 connectivity queries over chosen subsets.	Hard10	GraphBFS+2	No attempts yet	2s	512 MB	Judgeable
Dungeon 2Explore an unknown connected graph through a move-and-color oracle and report, for each i, how many room pairs have shortest-path distance exactly i.	Hard10	GraphBFS+2	No attempts yet	1s	256 MB	Judgeable
Shadow CompanionConstruct a fixed program over a bit tape with a shadow that transforms every input n < 2^10 into n squared.	Hard10	SimulationBit manipulation+2	No attempts yet	2s	512 MB	Judgeable
Delightful (Easy)Write a program of at most 100 commands for a ternary computer with 26 40-trit registers that computes the length of the longest non-decreasing prefix of the input in register X and leaves the answer in Y.	Hard10	ImplementationSimulation+2	No attempts yet	1s	512 MB	Judgeable
Xorshift64Given a start value x, find the 1-based index at which the target value t first appears in the xorshift64 sequence.	Hard10	MathBit manipulation+2	No attempts yet	2s	512 MB	Judgeable
No Description 2The statement gives no task, no input format, and no examples, so nothing about the required algorithm can be determined.	Hard10	Implementation	No attempts yet	2s	512 MB	Judgeable
HQ0-9+-INCOMPUTABLE?!Construct an HQ0-9+-INCOMPUTABLE?! program of at most 10000 commands whose final buffer equals a given target string.	Hard10	StringSimulation+2	No attempts yet	1s	1024 MB	Judgeable
Beautiful AutomataGiven a DAG, find the lexicographically smallest string whose suffix automaton is exactly this graph, or report -1 if none exists.	Hard10	GraphTopological sort+2	No attempts yet	2s	512 MB	Judgeable
Mysterious … HostFor each n up to N, find the minimum number of permutations needed so that every permutation of order n shares its answers to all consecutive-segment queries with one of them, modulo a prime P.	Hard10	CombinatoricsMath+2	No attempts yet	2s	256 MB	Judgeable
Fast BridgesGiven a k by k grid plus n bridges that cut travel time, find the sum of shortest distances over all cell pairs modulo 998244353.	Hard10	Shortest pathSorting+2	No attempts yet	2s	1024 MB	Judgeable
Rational Approximation	Unrated	Not classified yet	No attempts yet	1s	128 MB	Judgeable
Zu	Unrated	Not classified yet	No attempts yet	1s	256 MB	Judgeable
Star Pattern 15	Unrated	Not classified yet	No attempts yet	1s	256 MB	Judgeable
Star Pattern - 16	Unrated	Not classified yet	No attempts yet	1s	256 MB	Judgeable
Printing Stars 20	Unrated	Not classified yet	No attempts yet	1s	256 MB	Judgeable
Star pattern 22	Unrated	Not classified yet	No attempts yet	1s	256 MB	Judgeable
Project Team Vacation Schedule	Unrated	Not classified yet	No attempts yet	1s	512 MB	Judgeable
Maximum edge cost on a tree path	Unrated	Not classified yet	No attempts yet	2s	512 MB	Judgeable
Distinct weights on a tree path	Unrated	Not classified yet	No attempts yet	2s	512 MB	Judgeable
Glory Graph	Unrated	Not classified yet	No attempts yet	3s	512 MB	Judgeable
Cardiology	Unrated	Not classified yet	No attempts yet	2s	2048 MB	Judgeable
Spiral Matrix	Unrated	Not classified yet	No attempts yet	1s	256 MB	Judgeable
Nice Shape	Unrated	Not classified yet	No attempts yet	4s	512 MB	Judgeable
City Development	Unrated	Not classified yet	No attempts yet	3s	512 MB	Judgeable
Distributing the Treasure	Unrated	Not classified yet	No attempts yet	4s	1024 MB	Judgeable
Postman	Unrated	Not classified yet	No attempts yet	8s	256 MB	Judgeable
Amusement Arcade	Unrated	Not classified yet	No attempts yet	1s	1024 MB	Judgeable
ABBC	Unrated	Not classified yet	No attempts yet	3s	1024 MB	Judgeable
Special Prize	Unrated	Not classified yet	No attempts yet	2s	1024 MB	Judgeable
Changing Cards	Unrated	Not classified yet	No attempts yet	1.5s	1024 MB	Judgeable
Digesta	Unrated	Not classified yet	No attempts yet	1s	512 MB	Judgeable
Curious Shift	Unrated	Not classified yet	No attempts yet	1s	1024 MB	Judgeable
Kingdom	Unrated	Not classified yet	No attempts yet	1s	1024 MB	Judgeable
Authority	Unrated	Not classified yet	No attempts yet	2s	1024 MB	Judgeable
Keep in Touch	Unrated	Not classified yet	No attempts yet	1s	1024 MB	Judgeable
Make an X	Unrated	Not classified yet	No attempts yet	1s	1024 MB	Judgeable
Make an X (Hard)	Unrated	Not classified yet	No attempts yet	1s	1024 MB	Judgeable
Predicting the grass	Unrated	Not classified yet	No attempts yet	2s	1024 MB	Judgeable
String Tower	Unrated	Not classified yet	No attempts yet	1s	512 MB	Judgeable
Two-dimensional array	Unrated	Not classified yet	No attempts yet	1s	512 MB	Judgeable
Chocolate and the King Game	Unrated	Not classified yet	No attempts yet	1s	1024 MB	Judgeable
Odd/Even Strings	Unrated	Not classified yet	No attempts yet	1s	1024 MB	Judgeable
Check List	Unrated	Not classified yet	No attempts yet	1s	1024 MB	Judgeable
SGA President	Unrated	Not classified yet	No attempts yet	1s	1024 MB	Judgeable
I Love You, Yonsei	Unrated	Not classified yet	No attempts yet	1.885s	1024 MB	Judgeable
Interplanetary Study Meeting	Unrated	Not classified yet	No attempts yet	2s	1024 MB	Judgeable
Unbroken Spirit 3	Unrated	Not classified yet	No attempts yet	6s	1024 MB	Judgeable
Vertical Calendar	Unrated	Not classified yet	No attempts yet	1s	512 MB	Judgeable
Alternating Algorithm	Unrated	Not classified yet	No attempts yet	7s	1024 MB	Judgeable