Problems

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Total results29,455 problems

Yum Yum
Medium5
Math, Number theory+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sorting
Medium5
Sorting, Array+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Chocolate Wholesaler
Medium5
Probability, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cash Dispenser
Medium5
String, Dynamic programming+1
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Piggy Banks
Medium5
Graph, DFS+2
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
k-Even-Sum Sequence
Medium5
Greedy, Math+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Passage
Medium5
Dynamic programming, Bit manipulation+1
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Chocolate
Medium5
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tiles
Medium5
Number theory, Union-find+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Island
Medium5
Two pointers, Prefix sum+1
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Insulator
Medium5
Greedy, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Protocols
Medium5
Dynamic programming, Combinatorics+2
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Balance
Medium5
Dynamic programming, Sorting+2
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Ants and the Ladybug
Medium5
Tree, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Lollobrigida
Medium5
Greedy, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Repetitions
Medium5
String, Binary search+2
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Promotion
Medium5
Heap, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bitmap
Medium5
BFS, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
ATMs
Medium5
Bit manipulation, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Number of N-k-special Sets
Medium5
Dynamic programming, Combinatorics
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Monochromatic Triangles
Medium5
Combinatorics, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Building Blocks
Medium5
Dynamic programming, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Building Blocks
Medium5
Sliding window, Prefix sum+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Take-out
Medium5
Stack, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Matches
Medium5
Bit manipulation, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Non-consecutive Summands
Medium5
Greedy, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Orienteering
Medium5
Array, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Map
Medium5
Sorting, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Rectangles 2
Medium5
Math, Combinatorics+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Logarithmic Paprika
Medium5
Greedy, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Apples and Apple Trees
Medium5
Sorting, Binary search+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Balloons
Medium5
Greedy, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Electricity
Medium5
Dynamic programming, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Encyclopedia
Medium5
Greedy, Array+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sawmills
Medium5
Greedy, Stack+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Game
Medium5
Greedy, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Library
Medium5
Greedy, Heap
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sum of Divisor Counts
Medium5
Math, Number theory+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Crime at Piccadilly Circus
Medium5
Intervals, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Rubik's Cube Similarity
Medium5
Simulation, Brute force+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Dice
Medium5
Combinatorics, Dynamic programming+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Galactic Container Ship
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Super-Fast Circular Races
Medium5
Graph, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Viewing Terraces
Medium5
Sliding window, Two pointers+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Highways
Medium5
Minimum spanning tree, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Rural Postman
Medium5
Math, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Two Words
Medium5
Segment tree, String
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
The Traveler
Medium5
Simulation, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Buttons
Medium5
Simulation, Array
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Matches
Medium5
Dynamic programming, Prefix sum
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Brothers
Medium5
Greedy, Intervals+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Merchant
Medium5
Greedy, Prefix sum
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Car Workshops
Medium5
Simulation, Array
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Palindrome Numbers
Medium5
Math, String+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Warehouses
Medium5
Tree, Greedy+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Chemical Reactions
Medium5
BFS, Graph+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Telephone Exchange
Medium5
Geometry, Sorting+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Bitocja
Medium5
Shortest path, Graph
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Distance
Medium5
Greedy, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cities
Medium5
Array, Prefix sum
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Balls in a Binary Tree
Medium5
Bit manipulation, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Children
Medium5
Graph, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Raffle Tickets
Medium5
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Traffic Lanes
Medium5
Shortest path, BFS+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Paper Strip
Medium5
Hash map, Prefix sum
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Radiotelegraph
Medium5
Sliding window, Hash map
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Planting Potatoes
Medium5
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Equalizing Water in Glasses
Medium5
Greedy, Prefix sum
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Chinese Restaurants
Medium5
Tree, BFS
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Domino Tiles
Medium5
Graph, Hash map
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Board
Medium5
Greedy, Two pointers+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tower
Medium5
Binary search, Prefix sum
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Paper Rolls
Medium5
Sorting, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Forest
Medium5
Binary search, BFS+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Binary Sum
Medium5
Math, Bit manipulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bubu
Medium5
Shortest path, Graph
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Crossing
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Watchtowers
Medium5
Dynamic programming, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Neighborhood Rivalry
Medium5
Sliding window, Matrix+1
No attempts yet
Time limit
2.5s
Memory limit
128 MB
Judgeable
More Garden Troubles
Medium5
Greedy, Math+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Poetry with an Asterisk
Medium5
Hash map, String
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Konkotenacja
Medium5
Dynamic programming, Prefix sum+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Jas the Worm
Medium5
Tree, Binary search
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Word Translation Lookup
Medium5
Union-find, Hash map+1
No attempts yet
Time limit
12s
Memory limit
128 MB
Judgeable
Boards
Medium5
Bit manipulation, Greedy
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Reconstruct the Queue
Medium5
Segment tree
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Portal Kombat
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Miners
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Memory Bit Electrode Operations
Medium5
Greedy, String
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Neon Sign
Medium5
Combinatorics, Graph
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
The Lord of the Rings
Medium5
Simulation, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sizeof
Medium5
Recursion, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
MCS
Medium5
Sliding window, Hash map
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Salesmen
Medium5
Dynamic programming, Graph
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Phone Plot
Medium5
Geometry, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Meteor
Medium5
Intervals, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Symmetry
Medium5
Hash map, Geometry+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Graceful Prime Decomposition
Medium5
Dynamic programming, Number theory
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Math Notebook
Medium5
Brute force, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Parcel Delivery
Medium5
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Yum YumFind the minimum number of straight lines needed to cover every integer-coordinate point in an (n+1) by (m+1) grid, excluding the frog's one starting point.	Medium5	MathNumber theory+2	No attempts yet	1s	128 MB	Judgeable
SortingCount the swaps made by a given selection-style double loop on an array.	Medium5	SortingArray+1	No attempts yet	1s	128 MB	Judgeable
Chocolate WholesalerGiven n independent bars with individual surprise probabilities, find the probability that a carton has at least k surprises.	Medium5	ProbabilityDynamic programming	No attempts yet	1s	128 MB	Judgeable
Cash DispenserCount 4-digit PINs whose digits appear as a subsequence of every recorded finger-movement sequence.	Medium5	StringDynamic programming+1	No attempts yet	3s	128 MB	Judgeable
Piggy BanksEach key i sits in some bank; opening a bank frees its keys. Find the minimum number of banks to smash to reach all N banks.	Medium5	GraphDFS+2	No attempts yet	3s	128 MB	Judgeable
k-Even-Sum SequenceChange the fewest elements so that every contiguous block of length k in the sequence has an even sum.	Medium5	GreedyMath+2	No attempts yet	1s	256 MB	Judgeable
PassageSplit n people into groups whose total weight is at most W, minimizing the sum of each group's slowest crossing time.	Medium5	Dynamic programmingBit manipulation+1	No attempts yet	3s	128 MB	Judgeable
ChocolateFind the minimum total cost to split an m by n chocolate bar into unit squares, where each vertical or horizontal cut costs a fixed price regardless of the piece size.	Medium5	GreedySorting	No attempts yet	1s	128 MB	Judgeable
TilesGiven n, k, l, find the number of equivalence classes of positions 1..n under the equivalence generated by steps of ±k and ±l.	Medium5	Number theoryUnion-find+1	No attempts yet	1s	128 MB	Judgeable
IslandGiven the edge lengths of a cycle, find the maximum over all pairs of towns of the shorter of the two arc distances.	Medium5	Two pointersPrefix sum+1	No attempts yet	3s	512 MB	Judgeable
InsulatorGiven n positive coefficients, reorder them so that the sum plus the total of positive rises between adjacent layers is as large as possible, and print that maximum.	Medium5	GreedySorting+2	No attempts yet	1s	128 MB	Judgeable
ProtocolsCount the length-m strings over k symbols with no run of l equal symbols, then output floor((n/m) * log2(count)).	Medium5	Dynamic programmingCombinatorics+2	No attempts yet	3s	128 MB	Judgeable
BalanceGiven weights, split some into two equal-sum disjoint groups; find the largest weight that can be the heaviest used one.	Medium5	Dynamic programmingSorting+2	No attempts yet	3s	128 MB	Judgeable
Ants and the LadybugSimulate guards moving on a tree toward successive ladybug landings, respecting blocking rules, and report each ant's final place and chase count.	Medium5	TreeSimulation+2	No attempts yet	1s	128 MB	Judgeable
LollobrigidaGiven a multiset of block heights, decide whether the blocks can be arranged so the sequence alternates up and down at every position.	Medium5	GreedySorting+2	No attempts yet	1s	128 MB	Judgeable
RepetitionsGiven up to five lowercase words of length at most 2000, find the length of the longest substring that appears as a contiguous fragment in every word.	Medium5	StringBinary search+2	No attempts yet	3s	128 MB	Judgeable
PromotionEach day, receipts are added to a box, then the largest and smallest are removed and the difference is paid out; find the total payout.	Medium5	HeapImplementation+2	No attempts yet	1s	128 MB	Judgeable
BitmapFor each black pixel in an n by m bitmap, output the Manhattan distance to the closest white pixel.	Medium5	BFSGraph+1	No attempts yet	1s	128 MB	Judgeable
ATMsFor each amount under 10^30, find a subset of the 100 ATMs whose signed sum equals the amount and another equal to its negation.	Medium5	Bit manipulationGreedy+1	No attempts yet	1s	128 MB	Judgeable
The Number of N-k-special SetsCount subsets of {1,...,n} with no two consecutive numbers whose sum exceeds k, for n up to 100.	Medium5	Dynamic programmingCombinatorics	No attempts yet	1s	128 MB	Judgeable
Monochromatic TrianglesGiven n points and a list of red edges (all other pairs are black), count the triangles whose three sides share one color.	Medium5	CombinatoricsGraph+2	No attempts yet	1s	128 MB	Judgeable
Building BlocksRemove blocks from a tower so the most remaining blocks sit at an altitude equal to their printed number.	Medium5	Dynamic programmingGreedy+1	No attempts yet	1s	128 MB	Judgeable
Building BlocksFind the minimum number of add/remove block moves so that some k consecutive columns end up with equal height.	Medium5	Sliding windowPrefix sum+2	No attempts yet	1s	128 MB	Judgeable
Take-outA white block is 'b' and a black block is 'c'. Scan a row of blocks with a stack; whenever the top k+1 blocks hold k white and one black, pop and record them, then print the recorded groups in reverse order.	Medium5	StackSimulation+1	No attempts yet	1s	128 MB	Judgeable
MatchesGiven m match lineups that each split n boys into two teams, decide whether every pair of boys is separated at least once.	Medium5	Bit manipulationCombinatorics+1	No attempts yet	1s	128 MB	Judgeable
Non-consecutive SummandsSplit a positive integer into the most distinct parts possible, none of which are consecutive.	Medium5	GreedyMath+1	No attempts yet	1s	128 MB	Judgeable
OrienteeringGiven the cyclic sequence of stage difficulties around a loop, decide whether some starting point and direction make the difficulties non-increasing.	Medium5	ArrayGreedy+1	No attempts yet	1s	128 MB	Judgeable
MapCount the marked points that have at least one point strictly below-left, above-right, below-right, and above-left of them.	Medium5	SortingArray	No attempts yet	1s	128 MB	Judgeable
Rectangles 2Count axis-aligned rectangles with vertices on grid points of an n x m grid whose perimeter is at least p.	Medium5	MathCombinatorics+2	No attempts yet	2s	512 MB	Judgeable
Logarithmic PaprikaGiven counts of paprika weighing 1, 2, 4, ..., 2^k grams, find the smallest positive weight that cannot be formed from whole pieces.	Medium5	GreedyMath+2	No attempts yet	1s	128 MB	Judgeable
Apples and Apple TreesGiven positions of n trees and m apples on a line, find the minimum distance from any apple to its nearest tree.	Medium5	SortingBinary search+2	No attempts yet	1s	128 MB	Judgeable
BalloonsGiven stock counts for n balloon colors and m orders, decide whether each child can receive the requested number of distinct-colored balloons.	Medium5	GreedySorting+2	No attempts yet	1s	128 MB	Judgeable
ElectricityGiven k lines between n homes and m windmills on parallel lines, count subsets of non-crossing lines where every home and windmill has degree at most one, modulo r.	Medium5	Dynamic programmingSorting+1	No attempts yet	1s	128 MB	Judgeable
EncyclopediaGiven a stack of n pages and n sleeves, swap adjacent elements to make the two types alternate, and output the minimum number of swaps.	Medium5	GreedyArray+2	No attempts yet	1s	128 MB	Judgeable
SawmillsGiven a string of g and t points along a line, pair every g with a distinct t using non-crossing north-side arcs so the summed distance is minimal, or report NIE.	Medium5	GreedyStack+2	No attempts yet	1s	128 MB	Judgeable
The GameFor n black and n white pawns on a line of 2n+1 squares with one gap, find the minimum number of shifts and jumps to swap the two colors.	Medium5	GreedyMath+1	No attempts yet	1s	128 MB	Judgeable
LibraryMerge n files two at a time, where each merge costs the sum of the two lengths, and minimize the total cost.	Medium5	GreedyHeap	No attempts yet	1s	128 MB	Judgeable
Sum of Divisor CountsGiven n up to 10^12, compute the sum of divisor counts d(1)+d(2)+...+d(n) efficiently.	Medium5	MathNumber theory+1	No attempts yet	1s	128 MB	Judgeable
Crime at Piccadilly CircusFor each integer moment in [p, k], count how many people's inclusive intervals cover it, and report the minimum and maximum counts.	Medium5	IntervalsSorting+2	No attempts yet	1s	128 MB	Judgeable
Rubik's Cube SimilarityGiven two unfolded cube nets, find the smallest number of stickers to repaint on the second cube over all 24 rotations to match the first.	Medium5	SimulationBrute force+2	No attempts yet	1s	128 MB	Judgeable
DiceFind the k-th non-decreasing sequence of length m with values from 1 to n, in lexicographic order.	Medium5	CombinatoricsDynamic programming+2	No attempts yet	1s	128 MB	Judgeable
Galactic Container ShipGiven M rails with height limits 1..M and N plates each worth its quality w and having height h, choose plates to maximize total quality so that each chosen plate fits some distinct rail.	Medium5	GreedySorting+1	No attempts yet	1s	128 MB	Judgeable
Super-Fast Circular RacesGiven a directed graph where each vertex has out-degree and in-degree at most two, count the ways to cover every vertex with vertex-disjoint simple directed cycles, modulo 10000, or report NIE if impossible.	Medium5	GraphDFS+2	No attempts yet	1s	128 MB	Judgeable
Viewing TerracesIn a chain of terraces where climbing up costs height difference and descending is free, find the most distinct terraces reachable on k credits without returning to ground.	Medium5	Sliding windowTwo pointers+1	No attempts yet	1s	128 MB	Judgeable
HighwaysFind a spanning tree of a connected weighted graph that minimizes the maximum edge weight, and report that weight.	Medium5	Minimum spanning treeGraph+2	No attempts yet	1s	128 MB	Judgeable
The Rural PostmanStart at village 1 and cover every road and village to maximize order-based village payments minus one euro per move.	Medium5	MathGraph+1	No attempts yet	1s	128 MB	Judgeable
Two WordsAfter each swap of one character between the two strings, report which string is lexicographically larger.	Medium5	Segment treeString	No attempts yet	1s	512 MB	Judgeable
The TravelerCompute the height and width of the smallest axis-aligned rectangle containing a walk given in repeated direction blocks.	Medium5	SimulationPrefix sum+1	No attempts yet	1s	512 MB	Judgeable
ButtonsSimulate single counter increments and global max-fill operations to find the final counter values.	Medium5	SimulationArray	No attempts yet	1s	512 MB	Judgeable
MatchesFlip the fewest matches in a row so fire lit at the left end spreads through every neighboring pair.	Medium5	Dynamic programmingPrefix sum	No attempts yet	1s	512 MB	Judgeable
BrothersChoose the largest set of families whose position spans never overlap so each kept family stands together.	Medium5	GreedyIntervals+1	No attempts yet	1s	512 MB	Judgeable
MerchantBuy in one city and sell in another along a line to maximize selling price minus buying price minus travel cost.	Medium5	GreedyPrefix sum	No attempts yet	1s	512 MB	Judgeable
Car WorkshopsCars pass through workshops in order and each one repaints color a to b on a match, so compute every final color.	Medium5	SimulationArray	No attempts yet	1s	512 MB	Judgeable
Palindrome NumbersGiven a decimal integer with up to 1000 digits, print its representation in each base from 2 to 10 where it reads as a palindrome.	Medium5	MathString+1	No attempts yet	1s	128 MB	Judgeable
WarehousesMove goods along tree roads so every warehouse holds the average amount at minimum transport cost.	Medium5	TreeGreedy+1	No attempts yet	1s	512 MB	Judgeable
Chemical ReactionsCount unowned compounds that become producible by repeatedly firing reactions whose substrates are all available.	Medium5	BFSGraph+1	No attempts yet	1s	512 MB	Judgeable
Telephone ExchangePick an integer tower height so the fees from houses fully covered by the circle exceed the height-dependent maintenance cost by as much as possible.	Medium5	GeometrySorting+2	No attempts yet	1s	512 MB	Judgeable
BitocjaThe program accepts each proposed road in order only when it strictly shortens the shortest travel time from city 1 to city n.	Medium5	Shortest pathGraph	No attempts yet	1s	512 MB	Judgeable
DistanceChoose two array elements, possibly the same element twice, to maximize the sum of the two values plus the distance between their positions.	Medium5	GreedyArray	No attempts yet	1s	128 MB	Judgeable
CitiesCount for each city on a directed line how many other cities are reachable through one-way and two-way roads.	Medium5	ArrayPrefix sum	No attempts yet	1s	128 MB	Judgeable
Balls in a Binary TreeFollow the n-th ball down h levels of toggling switches, going left on odd visits and right on even visits, to find its leaf number.	Medium5	Bit manipulationSimulation+1	No attempts yet	1s	128 MB	Judgeable
ChildrenGiven a permutation on n cells, find the fewest adjacent swaps so every walk visits all cells.	Medium5	GraphArray	No attempts yet	1s	128 MB	Judgeable
Raffle TicketsBuy tickets from baskets with known winning and losing counts to guarantee at least g wins with the fewest tickets.	Medium5	Dynamic programming	No attempts yet	1s	128 MB	Judgeable
Traffic LanesFind the fewest lane changes needed to drive across an n by m grid of blocked and free cells, starting and ending in any lane.	Medium5	Shortest pathBFS+1	No attempts yet	1s	128 MB	Judgeable
Paper StripFind the longest contiguous block of numbers that adds up to exactly s, or print BRAK when none exists.	Medium5	Hash mapPrefix sum	No attempts yet	1s	128 MB	Judgeable
RadiotelegraphGiven n integers and at most w changes to any values, find the longest run of equal numbers achievable.	Medium5	Sliding windowHash map	No attempts yet	1s	128 MB	Judgeable
Planting PotatoesDistribute up to m potatoes over fields capped at b_i so the sum of squared counts is as large as possible.	Medium5	GreedySorting	No attempts yet	1s	128 MB	Judgeable
Equalizing Water in GlassesGiven the water levels in n adjacent glasses, find the fewest pours between neighbors that make all levels equal.	Medium5	GreedyPrefix sum	No attempts yet	1s	128 MB	Judgeable
Chinese RestaurantsPick the intersection that minimizes the farthest distance to a marked restaurant and report that distance, or -1 when no restaurant exists.	Medium5	TreeBFS	No attempts yet	1s	128 MB	Judgeable
Domino TilesCount pip frequencies to find the two odd endpoints of the domino chain, or report ambiguity when the chain can start anywhere.	Medium5	GraphHash map	No attempts yet	1s	128 MB	Judgeable
The BoardFind the longest string of zeros followed by ones that appears as a subsequence of both given binary sequences.	Medium5	GreedyTwo pointers+1	No attempts yet	1s	128 MB	Judgeable
TowerEach resident climbs the steps from the bottom and stops before the first step whose height reaches their own.	Medium5	Binary searchPrefix sum	No attempts yet	1s	128 MB	Judgeable
Paper RollsSet every roll to one shared unrolled length within each total length using the fewest 1-cm moves.	Medium5	SortingMath	No attempts yet	1s	128 MB	Judgeable
ForestFind the smallest possible oldest-tree age among all edge-connected groups of exactly d trees in an n by n age grid.	Medium5	Binary searchBFS+1	No attempts yet	1s	128 MB	Judgeable
Binary SumGiven k, print in binary the sum of all integers from 1 to the largest k-digit binary number.	Medium5	MathBit manipulation	No attempts yet	1s	128 MB	Judgeable
BubuFind Bubu's fastest route to clearing 1 that reaches every clearing before any ranger does, or report -1.	Medium5	Shortest pathGraph	No attempts yet	1s	128 MB	Judgeable
The CrossingPair at most two riders per shared boat within the weight limit or send each alone, and find the lowest total fare.	Medium5	GreedySorting+1	No attempts yet	2s	128 MB	Judgeable
WatchtowersFind the maximum sum over any nonempty block of consecutive towers arranged in a circle.	Medium5	Dynamic programmingArray	No attempts yet	1s	128 MB	Judgeable
Neighborhood RivalryEach cell of the grid needs the maximum value inside the square of radius R centered on it.	Medium5	Sliding windowMatrix+1	No attempts yet	2.5s	128 MB	Judgeable
More Garden TroublesFind the fewest flamethrower shots that clear every plot when each shot halves a plot and its two neighbors, rounding down.	Medium5	GreedyMath+1	No attempts yet	2s	128 MB	Judgeable
Poetry with an AsteriskCount for each one-asterisk query how many dictionary words start with its prefix and end with its suffix without overlap.	Medium5	Hash mapString	No attempts yet	5s	128 MB	Judgeable
KonkotenacjaCount the ways to split the word into nonempty pieces joined by the literal separator kot, modulo 1000000007.	Medium5	Dynamic programmingPrefix sum+1	No attempts yet	2s	128 MB	Judgeable
Jas the WormA rooted tree grows one leaf at a time while Jas steps once toward each queried vertex, and the task reports his landing vertex after every move.	Medium5	TreeBinary search	No attempts yet	1s	128 MB	Judgeable
Word Translation LookupGiven pairs of directly translated words, list every target-language word linked to each query word through translation chains.	Medium5	Union-findHash map+1	No attempts yet	12s	128 MB	Judgeable
BoardsFrom the smallest power of two at least K, find the fewest board halvings so some pieces sum to exactly K.	Medium5	Bit manipulationGreedy	No attempts yet	1s	128 MB	Judgeable
Reconstruct the QueueGiven each arrival's insertion spot in a growing queue, compute every person's final position at dispersal.	Medium5	Segment tree	No attempts yet	1s	128 MB	Judgeable
Portal KombatHektor absorbs the strength of each weaker opponent he beats, and the goal is the fewest wins that let him defeat the strongest opponent.	Medium5	GreedySorting+1	No attempts yet	5s	128 MB	Judgeable
MinersAssign each miner to a leaf chamber whose path from the entrance stays tall enough and fit as many miners as possible.	Medium5	GreedySorting+1	No attempts yet	2s	128 MB	Judgeable
Memory Bit Electrode OperationsYou receive start and target binary strings and compute the fewest prefix or suffix flips that turn the start into the target.	Medium5	GreedyString	No attempts yet	1s	128 MB	Judgeable
Neon SignCount the triples of vertices whose three connecting tubes all share the same color in a red-blue complete graph.	Medium5	CombinatoricsGraph	No attempts yet	3s	256 MB	Judgeable
The Lord of the RingsDecide whether a fixed attacker force can conquer all letter-named countries on a grid by choosing a suitable attack order.	Medium5	SimulationGraph+1	No attempts yet	1s	128 MB	Judgeable
SizeofRead a word size and a nested struct declaration and compute its storage size with word alignment.	Medium5	RecursionImplementation+1	No attempts yet	1s	128 MB	Judgeable
MCSCount every length-k substring of a DNA string by its letter composition and report the size of the largest group.	Medium5	Sliding windowHash map	No attempts yet	5s	128 MB	Judgeable
SalesmenGiven a graph and a reported vertex sequence, find the fewest entries to change so consecutive vertices stay put or follow an edge.	Medium5	Dynamic programmingGraph	No attempts yet	1s	128 MB	Judgeable
Phone PlotClassify each phone number as EXCELLENT, GOOD, or BAD by counting the fewest straight segments that cover its keypad trace.	Medium5	GeometrySimulation+1	No attempts yet	1s	128 MB	Judgeable
MeteorThe task counts the largest number of meteors strictly inside a fixed rectangle at one moment as each meteor moves along a straight path.	Medium5	IntervalsSorting+1	No attempts yet	1s	128 MB	Judgeable
SymmetryDecide whether the given dots mirror exactly across some vertical line, printing YES or NO for each test case.	Medium5	Hash mapGeometry+1	No attempts yet	1s	128 MB	Judgeable
Graceful Prime DecompositionCount ordered sums of N from primes up to K where no two neighboring primes are equal.	Medium5	Dynamic programmingNumber theory	No attempts yet	1s	128 MB	Judgeable
Math NotebookChoose a contiguous block from both sequences to maximize its dot product with the reversed second block.	Medium5	Brute forceArray	No attempts yet	1s	128 MB	Judgeable
Parcel DeliveryChoose how many boxes of each shipment to load onto a one-way truck of capacity C to maximize total delivered boxes.	Medium5	GreedySorting	No attempts yet	1s	128 MB	Judgeable