Interview core

Mediums from real onsites

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Total results3,610 problems

The Die Is Cast
Medium5
Graph, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Spiderman's Workout
Medium5
Dynamic programming, Greedy+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tournament Ranking
Medium5
Graph, Topological sort+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Traffic Planning
Medium5
Graph, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Median Weight Bead
Medium5
Graph, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Alice Through the Looking Glass
Medium5
Recursion, Divide and conquer+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Putnam Rank Range
Medium5
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Spies Like Us
Medium5
Graph, Hash map+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Barking Dogs!
Medium5
Simulation, Graph+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Shuffle
Medium5
Implementation, Math+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
CN Tower
Medium5
Sorting, Two pointers+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bananas
Medium5
String, Recursion+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Pinball Ranking
Medium5
Binary search, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Spreadsheet
Medium5
Graph, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Scribble
Medium5
String, Hash map+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cookies
Medium5
Geometry, Brute force+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Subsets
Medium5
Graph, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Divided Fractals
Medium5
Recursion, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Pattern Generator
Medium5
Backtracking, Recursion+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
All Roads Lead Where?
Medium5
Tree, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tree Cutting
Medium5
Tree, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Journey of a Knight
Medium5
BFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Gears
Medium5
Math, Number theory+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Tax System
Medium5
Prefix sum, Binary search+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Mõttemeister
Medium5
Brute force, Implementation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Tähekabe
Medium5
Backtracking, DFS+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Go-Kart
Medium5
Binary search, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Sawtooth Sequence
Medium5
Greedy, Sorting+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Animals
Medium5
Intervals, Implementation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Courier
Medium5
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Chocolate
Medium5
Matrix, Implementation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Spacecraft Malfunction
Medium5
Brute force, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Parentheses Encoding Conversion
Medium5
Stack, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Space Ant
Medium5
Geometry, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Wooden Sticks
Medium5
Sorting, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Repeated Permutation Cipher
Medium5
Array, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Card Game Cheater
Medium5
Greedy, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Investment
Medium5
Dynamic programming, Greedy
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Gunman
Medium5
Geometry, Binary search+2
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Divisibility
Medium5
Dynamic programming, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
False Coin
Medium5
Brute force, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Spell Checker
Medium5
String, Hash map+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bin Packing
Medium5
Greedy, Two pointers+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Dancers
Medium5
Sorting, Geometry+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Playground Hideout
Medium5
Shortest path, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Olympic Games
Medium5
Greedy, Sorting+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Relocation
Medium5
Dynamic programming, Binary search+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Number Tricks
Medium5
Number theory, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Betting Sets
Medium5
Dynamic programming, Bit manipulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Polling Stations
Medium5
Graph, Greedy
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Deepest Station
Medium5
Geometry, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Outlets
Medium5
Greedy, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Digit Sum Over a Range
Medium5
Math, Dynamic programming+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Avoiding Financial Nightmare
Medium5
Binary search, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
No Pause Telegraph
Medium5
Dynamic programming, String+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Romantic Date
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Nearest number - 2
Medium5
BFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Pearls
Medium5
Dynamic programming, Prefix sum+1
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
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
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
Monochromatic Triangles
Medium5
Combinatorics, Graph+2
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
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
Library
Medium5
Greedy, Heap
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
Galactic Container Ship
Medium5
Greedy, Sorting+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
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
Chemical Reactions
Medium5
BFS, Graph+1
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
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

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
The Die Is CastRead a pixel image, split non-background pixels into dice connected by shared edges, count the dot regions inside each die, and print the counts sorted.	Medium5	GraphDFS+2	No attempts yet	1s	128 MB	Judgeable
Spiderman's WorkoutAssign plus or minus signs to the distances so the partial sums stay at or above 0 and return to 0 at the end, minimizing the peak height.	Medium5	Dynamic programmingGreedy+2	No attempts yet	1s	128 MB	Judgeable
Tournament RankingGiven game results between teams, produce the lexicographically smallest topological order, or report that no valid ranking exists due to a cycle.	Medium5	GraphTopological sort+2	No attempts yet	1s	128 MB	Judgeable
Traffic PlanningGiven a directed graph and a start node, list the nodes not reachable from the start by a path of one or more edges; print OK if none.	Medium5	GraphDFS+2	No attempts yet	1s	128 MB	Judgeable
Median Weight BeadGiven weighted comparisons between beads, count how many beads cannot be the median because at least (N+1)/2 beads are known heavier or lighter.	Medium5	GraphDFS+2	No attempts yet	1s	128 MB	Judgeable
Alice Through the Looking GlassGiven a magnification level and a cell coordinate, decide whether that cell of the 5^m by 5^m self-similar grid is filled or empty.	Medium5	RecursionDivide and conquer+1	No attempts yet	2s	512 MB	Judgeable
Putnam Rank RangeGiven the average rank for each distinct score, find the rank range occupied by the block of contestants holding your score.	Medium5	MathImplementation	No attempts yet	2s	512 MB	Judgeable
Spies Like UsGiven a bipartite graph, decide whether any two vertices on the same side share at most one common neighbor on the other side.	Medium5	GraphHash map+2	No attempts yet	2s	512 MB	Judgeable
Barking Dogs!Given dogs with wake-up delays and a directed hearing graph, simulate who barks each second from 0 to T and count each dog's barks.	Medium5	SimulationGraph+2	No attempts yet	2s	512 MB	Judgeable
ShuffleGiven a permutation of 27 characters, apply it N times to a short string and print the result.	Medium5	ImplementationMath+2	No attempts yet	2s	512 MB	Judgeable
CN TowerGiven angles of landmarks around a rotating restaurant that turns 360 degrees every 72 minutes, find the shortest time window covering all distinct angles.	Medium5	SortingTwo pointers+2	No attempts yet	1s	128 MB	Judgeable
BananasDecide for each word whether it fits the recursive grammar of a monkey language, where words wrap other words in N and in B...S.	Medium5	StringRecursion+2	No attempts yet	1s	128 MB	Judgeable
Pinball RankingGiven scores in play order, compute each game's rank as one plus the number of earlier-or-later scores strictly above it, then output the average rank as a reduced fraction.	Medium5	Binary searchSorting+2	No attempts yet	1s	128 MB	Judgeable
SpreadsheetEvaluate each spreadsheet cell, treating formula cells as sums of other cells, and mark any cell involved in a dependency cycle as undefined.	Medium5	GraphDFS+2	No attempts yet	1s	128 MB	Judgeable
ScribbleGiven seven tiles with letter values and a dictionary of up to 100000 words, find the highest-scoring dictionary word formable from the tiles, or 0 if none is.	Medium5	StringHash map+2	No attempts yet	1s	128 MB	Judgeable
CookiesGiven up to 10 points, find the diameter of the smallest enclosing circle.	Medium5	GeometryBrute force+2	No attempts yet	1s	128 MB	Judgeable
SubsetsGiven inequalities where a set name contains either an element or another set name, find each named set's minimal required elements.	Medium5	GraphDFS+2	No attempts yet	1s	128 MB	Judgeable
Divided FractalsPrint a rectangle of an iterated square fractal, with rows numbered bottom to top and cells joined by spaces.	Medium5	RecursionImplementation+2	No attempts yet	1s	128 MB	Judgeable
Pattern GeneratorFor each (n, k) pair, print all n-bit strings with exactly k ones in decreasing numeric order, separated by blank lines.	Medium5	BacktrackingRecursion+2	No attempts yet	1s	128 MB	Judgeable
All Roads Lead Where?Given a tree of cities rooted at Rome and query pairs, print the unique shortest path between each pair as the first letters of the cities on the route.	Medium5	TreeDFS+2	No attempts yet	1s	128 MB	Judgeable
Tree CuttingOn a tree of N nodes, print every node whose removal leaves each connected piece with at most floor(N/2) nodes, or NONE.	Medium5	TreeDFS+2	No attempts yet	1s	128 MB	Judgeable
Journey of a KnightGiven an n by m board, find the minimum number of knight moves from cell (1,1) to cell (i,j), or report that it is unreachable.	Medium5	BFSGraph+2	No attempts yet	1s	128 MB	Judgeable
GearsCount how many distinct fractions a/b exist with both a and b in the range M to N.	Medium5	MathNumber theory+2	No attempts yet	1s	1024 MB	Judgeable
Tax SystemEach client's income is taxed through N progressive brackets with given widths and rates; compute the total tax for M clients, printed to two decimals.	Medium5	Prefix sumBinary search+2	No attempts yet	1s	1024 MB	Judgeable
MõttemeisterGiven several guesses and their correct-digit counts A and position counts B, list every 4-digit secret number consistent with all clues.	Medium5	Brute forceImplementation+2	No attempts yet	1s	1024 MB	Judgeable
TähekabeOn an N x N letter grid, decide for each of up to 10 query words whether a simple path from the start cell spells it, without reusing a cell.	Medium5	BacktrackingDFS+2	No attempts yet	1s	1024 MB	Judgeable
Go-KartFind the smallest fuel-tank capacity that lets a kart refuel at given stations and travel at least K kilometers.	Medium5	Binary searchGreedy+1	No attempts yet	1s	1024 MB	Judgeable
Sawtooth SequenceGiven N distinct numbers, arrange all of them into a zigzag sequence and output the lexicographically smallest such arrangement.	Medium5	GreedySorting+2	No attempts yet	1s	1024 MB	Judgeable
AnimalsGiven N daily active intervals, some crossing midnight, find whether all overlap at some moment and output the longest common sub-interval.	Medium5	IntervalsImplementation+2	No attempts yet	1s	1024 MB	Judgeable
CourierSimulate orders arriving over time: assign each to the free courier who delivers fastest, or drop it if all couriers are busy, and total each courier's earnings.	Medium5	SimulationImplementation+2	No attempts yet	1s	1024 MB	Judgeable
ChocolateGiven an M by N grid of labels, decide whether every label occupies exactly one solid axis-aligned rectangle.	Medium5	MatrixImplementation+1	No attempts yet	1s	1024 MB	Judgeable
Spacecraft MalfunctionGiven each unit's check reports on two others, exactly one faulty unit, and a faulty unit may lie, find the unique faulty unit or print impossible.	Medium5	Brute forceImplementation+2	No attempts yet	1s	128 MB	Judgeable
Parentheses Encoding ConversionGiven the P-sequence encoding of a well-formed parenthesis string, compute its W-sequence encoding.	Medium5	StackSimulation+1	No attempts yet	1s	128 MB	Judgeable
Space AntGiven N points with distinct x and y coordinates, output the order produced by repeatedly picking the most clockwise remaining point from the current one.	Medium5	GeometrySorting+2	No attempts yet	1s	128 MB	Judgeable
Wooden SticksGiven n sticks with length and weight, order them to minimize the number of setup steps, where a setup is needed unless both length and weight are nondecreasing from the previous stick.	Medium5	SortingGreedy+1	No attempts yet	1s	128 MB	Judgeable
Repeated Permutation CipherGiven a permutation key and a repeat count k, apply the permutation to each padded message k times and print the result.	Medium5	ArrayImplementation+2	No attempts yet	1s	128 MB	Judgeable
Card Game CheaterEve knows Adam's card order and must permute her own cards to maximize the number of positions where her card beats his.	Medium5	GreedySorting+2	No attempts yet	1s	128 MB	Judgeable
InvestmentStarting capital grows over at most 40 years by rebuying a portfolio of bonds each year; maximize the final amount.	Medium5	Dynamic programmingGreedy	No attempts yet	1s	128 MB	Judgeable
GunmanEach window is a rectangle at a distinct depth; decide whether one straight ray fired from the X axis can pass through all of them.	Medium5	GeometryBinary search+2	No attempts yet	2s	128 MB	Judgeable
DivisibilityGiven a sequence and a modulus K, decide whether some choice of + or - before each later element makes the total divisible by K.	Medium5	Dynamic programmingMath+2	No attempts yet	1s	128 MB	Judgeable
False CoinGiven recorded balance weighings of N coins with exactly one false coin, output the coin number if the results identify it uniquely, otherwise 0.	Medium5	Brute forceImplementation+2	No attempts yet	1s	128 MB	Judgeable
Spell CheckerGiven a dictionary and query words, mark each query correct, or list dictionary words reachable by one deletion, replacement, or insertion.	Medium5	StringHash map+2	No attempts yet	1s	128 MB	Judgeable
Bin PackingPack items into identical bins holding at most two items each so that the number of bins is minimized.	Medium5	GreedyTwo pointers+2	No attempts yet	1s	128 MB	Judgeable
DancersRepeatedly pair the two closest unpaired dancers, breaking ties by smaller indices, and output all pairs sorted.	Medium5	SortingGeometry+2	No attempts yet	1s	128 MB	Judgeable
Playground HideoutGiven a directed graph with weighted edges and direct ground costs per node, find the index of the node with the largest shortest-path distance from ground, breaking ties by smallest index.	Medium5	Shortest pathGraph+2	No attempts yet	1s	128 MB	Judgeable
Olympic GamesGiven each event's date and start and end times in hhmm, find the maximum number of events a person can attend without overlap, moving freely between venues.	Medium5	GreedySorting+2	No attempts yet	2s	256 MB	Judgeable
RelocationSplit up to 10 furniture items between two cars with capacity limits so that every item gets moved in the fewest number of paired trips.	Medium5	Dynamic programmingBinary search+2	No attempts yet	1s	128 MB	Judgeable
Number TricksFor each query, count the trailing zeros of n! in base b by factoring b and finding the minimum over primes of each exponent's count in n!.	Medium5	Number theoryMath+2	No attempts yet	1s	128 MB	Judgeable
Betting SetsPartition an N by M table of probabilities into groups of one cell per column to maximize the expected number of all-heads groups.	Medium5	Dynamic programmingBit manipulation+2	No attempts yet	1s	128 MB	Judgeable
Polling StationsGiven an undirected graph, find the smallest set of vertices such that every edge touches at least one chosen vertex.	Medium5	GraphGreedy	No attempts yet	1s	64 MB	Judgeable
Deepest StationGiven a surface point (x, y) and depth d, decide whether a single 45-degree staircase reaches (0,0,d), it is impossible, or print the shallowest intermediate lobby.	Medium5	GeometryMath+1	No attempts yet	1s	128 MB	Judgeable
OutletsGiven power strips that swap between standard A and B outlets, find the maximum number of standard-A outlets that can end up powering computers.	Medium5	GreedySorting+2	No attempts yet	1s	128 MB	Judgeable
Digit Sum Over a RangeGiven l and u up to 2e9, find the total of the digit sums of every integer in that inclusive range.	Medium5	MathDynamic programming+2	No attempts yet	1s	128 MB	Judgeable
Avoiding Financial NightmareGiven a loan principal, a term in months, and a monthly interest rate, find the fixed monthly payment so the balance hits zero at term end.	Medium5	Binary searchSimulation+2	No attempts yet	1s	128 MB	Judgeable
No Pause TelegraphGiven a string of dots and dashes and seven fixed letter codes, split it into codewords that minimize the resulting message alphabetically, or report that no split exists.	Medium5	Dynamic programmingString+2	No attempts yet	1s	128 MB	Judgeable
Romantic DateGiven Wibowo's 26 cards, find the maximum number of rounds he can win by pairing his cards against his opponent's 26 cards in the best order.	Medium5	GreedySorting+1	No attempts yet	1s	128 MB	Judgeable
Nearest number - 2Replace each zero with the nearest nonzero value using Manhattan distance, but leave zeros that are tied between two or more nearest values unchanged.	Medium5	BFSGraph+2	No attempts yet	1s	128 MB	Judgeable
PearlsGiven demand and price per pearl for classes in increasing quality order, find the cheapest way to buy all pearls when each class's order may be upgraded to a higher class, paying 10 extra pearls' worth per purchase.	Medium5	Dynamic programmingPrefix sum+1	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
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
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
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
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
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
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
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
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
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
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
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
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
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