Problems

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Total results3,683 problems

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Stock MarketFind the contiguous subarray with the largest sum and report its 1-based start and end indices, breaking ties by smallest start then smallest end.	Medium5	Dynamic programmingGreedy	No attempts yet	1s	256 MB	Judgeable
Venus RoverChoose which stones to collect so total value is maximized, given limits on time and total lifted mass.	Medium5	Dynamic programming	No attempts yet	1s	128 MB	Judgeable
FashionistaFor each day pick any clothing whose temperature range covers that day's high, maximizing the sum of absolute flashiness differences between consecutive days.	Medium5	Dynamic programmingArray+2	No attempts yet	1s	128 MB	Judgeable
JOI FlagCount fillings of an M by N grid with J, O, I (some cells fixed) that contain at least one L shape: J with O to its right and I below, modulo 100000.	Medium5	Dynamic programmingCombinatorics+2	No attempts yet	5s	128 MB	Judgeable
Commute RouteCount monotone lattice paths from (1,1) to (w,h) that never turn at two consecutive intersections, modulo 100000.	Medium5	Dynamic programmingArray+2	No attempts yet	1s	128 MB	Judgeable
StrollSimulate the letters on a grid as N successive walks from the top-left, and report the endpoint of the N-th walk.	Medium5	SimulationDynamic programming+1	No attempts yet	2s	128 MB	Judgeable
Longest Common SubstringGiven two uppercase strings of length up to 4000, find the length of the longest substring that occurs contiguously in both.	Medium5	Dynamic programmingString+2	No attempts yet	2s	256 MB	Judgeable
FloodgatesEach gate drains Fi per hour at fixed cost Ci when opened. For each query (V, T), find the minimum total cost whose combined capacity Fi*T covers V.	Medium5	Brute forceGreedy+2	No attempts yet	1s	128 MB	Judgeable
Child PlayGiven domino-like slabs, orient and order them so both rows sum equally, discarding one slab only if necessary and preferring the smallest minimum half.	Medium5	Dynamic programmingGreedy+2	No attempts yet	1s	128 MB	Judgeable
SupermarketGiven a shopping list and products in path order, buy the list items in order from later positions at minimum total cost, or report impossible.	Medium5	Dynamic programmingArray+2	No attempts yet	1s	128 MB	Judgeable
Milk SchedulingGiven task durations and precedence constraints that form a DAG, find the minimum makespan when unlimited workers milk cows in parallel.	Medium5	GraphTopological sort+2	No attempts yet	1s	128 MB	Judgeable
BookshelfPartition the books in order into shelves whose widths sum to at most L, minimizing the total of each shelf's maximum height.	Medium5	Dynamic programmingArray+2	No attempts yet	1s	128 MB	Judgeable
Hay For SaleGiven a wagon capacity and a list of hay bale volumes, find the largest total volume not exceeding the capacity that can be formed by choosing whole bales.	Medium5	Dynamic programmingArray+2	No attempts yet	1s	128 MB	Judgeable
Cow Digit GameFor each starting number, players alternately subtract its largest or smallest nonzero digit, and the player who reaches 0 wins; decide if the first player wins.	Medium5	Dynamic programmingGame theory+2	No attempts yet	1s	128 MB	Judgeable
Cow CashCount the number of unordered ways to make an amount N using V coin denominations, where each coin can be used any number of times.	Medium5	Dynamic programmingCombinatorics+1	No attempts yet	1s	128 MB	Judgeable
Charm BraceletChoose a subset of N charms, each with a weight and a desirability, so that total weight stays within M and total desirability is maximized.	Medium5	Dynamic programmingArray+2	No attempts yet	1s	128 MB	Judgeable
Cow ContestGiven the winners of head-to-head matches, count how many cows have a skill rank that is fully forced by the results.	Medium5	GraphDFS+2	No attempts yet	1s	128 MB	Judgeable
Cow TravellingCount the number of walks of exactly T steps on a grid from a start cell to a target cell, where each step moves to a vertically or horizontally adjacent open cell.	Medium5	Dynamic programmingMatrix+2	No attempts yet	1s	128 MB	Judgeable
ATM PIN TheftGiven a sequence of observed key presses (digits and at most one backspace), count the four-digit PINs that could produce exactly that sequence of pressed keys.	Medium5	Dynamic programmingCombinatorics+2	No attempts yet	1s	128 MB	Judgeable
Hopeless CoachGiven past win, draw, and loss counts, find the probability that the team earns at least P points over the next N matches.	Medium5	Dynamic programmingProbability+2	No attempts yet	1s	128 MB	Judgeable
String ComputerCompute the minimum number of single-character insert, delete, or change operations needed to turn one string into another.	Medium5	Dynamic programmingString+2	No attempts yet	1s	128 MB	Judgeable
Extrapolation Using a Difference TableExtend a sequence by k steps using a polynomial difference table, always assuming the highest-order differences stay constant, and print the (n+k)-th term.	Medium5	MathDynamic programming+2	No attempts yet	1s	128 MB	Judgeable
El DoradoCount the increasing subsequences of length exactly k in a sequence of n distinct numbers, for several test cases.	Medium5	Dynamic programmingArray+1	No attempts yet	1s	128 MB	Judgeable
A Game with MarblesEach move takes one marble from a bowl and, if it is not bowl 1, adds one marble to every lower-numbered bowl; count the total moves until all bowls are empty.	Medium5	Dynamic programmingMath+1	No attempts yet	1s	128 MB	Judgeable
France '98Given win probabilities for every pair of 16 teams and a fixed bracket, compute each team's probability of winning the single-elimination tournament.	Medium5	Dynamic programmingProbability+2	No attempts yet	1s	128 MB	Judgeable
Humble NumbersFor each n up to 5842, print the nth number whose only prime factors are 2, 3, 5, or 7, formatted with the correct English ordinal suffix.	Medium5	Dynamic programmingMath+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
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
Choose Your Own ArithmeticGiven working digits and exactly W add-or-multiply steps applied left to right from a single digit, decide whether each target value is reachable.	Medium5	Brute forceDynamic programming+2	No attempts yet	2s	512 MB	Judgeable
NukitGiven counts of particles A, B, C, D, two players alternately remove one of five fixed multisets; find who wins under optimal play.	Medium5	Game theoryDynamic programming+2	No attempts yet	1s	128 MB	Judgeable
Super PlumberFind the maximum total coin value on a path from the bottom-left to the bottom-right of a grid where SP moves right, up, or down without revisiting cells.	Medium5	Dynamic programmingImplementation	No attempts yet	1s	128 MB	Judgeable
King Thrór's GoldCount the ways to choose exactly k distinct bar values summing to T, and list all solutions in lexicographic order when there are at most 20.	Medium5	Dynamic programmingBacktracking+2	No attempts yet	1s	128 MB	Judgeable
The Millionaire and the OrphansGiven three orphanages with fixed basket areas and children counts, compute the expected total gift value each orphanage catches as gifts are thrown in order.	Medium5	ProbabilityMath+1	No attempts yet	1s	1024 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
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
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
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
Balanced ChangeGiven counts of five coin types in a drawer and an amount, choose coins to give out so that the imbalance of the remaining coins is minimized.	Medium5	Dynamic programmingBrute force+1	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
Apocalyptic AlignmentGiven two A/B strings of equal length, find the minimum number of operations that repaint a contiguous segment with one fruit type to turn the first string into the second.	Medium5	Dynamic programmingGreedy+1	No attempts yet	1s	128 MB	Judgeable
Game DiceGiven up to 13 dice with various face counts and a target total, compute the probability of rolling exactly that sum, to five decimals.	Medium5	Dynamic programmingProbability+1	No attempts yet	1s	128 MB	Judgeable
FootballGiven pairwise win probabilities, find the team most likely to win a fixed single-elimination bracket of 2^n teams.	Medium5	Dynamic programmingProbability+1	No attempts yet	1s	128 MB	Judgeable
Three Bit ComputerGiven a string over {a,b,c}, decide whether an all-uninitialized memory can be initialized to exactly that string with the two given operations.	Medium5	Dynamic programmingGreedy	No attempts yet	1s	32 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
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
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
Afternoon TeaTrack the tea and milk levels in a cup over a sequence of half drinks and refills, and report which ingredient was consumed more.	Medium5	Dynamic programmingMath+1	No attempts yet	3s	32 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
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
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
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
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
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
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
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
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
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
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
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
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
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
TaekwondoSort both weight lists and pair players to minimize the total absolute weight difference across all matches.	Medium5	Dynamic programmingSorting	No attempts yet	1s	128 MB	Judgeable
Message BroadcastingCompute the fewest rounds to spread a message from the root when each informed node calls at most one child per round.	Medium5	GreedyTree+2	No attempts yet	1s	128 MB	Judgeable
Servicing ClientsChoose clients whose distance-times-demand costs fit the budget to maximize total priority.	Medium5	Dynamic programmingShortest path	No attempts yet	1s	128 MB	Judgeable
Tug of WarDecide whether N student weights (4 to 30) split into two teams whose total strengths differ by at most X.	Medium5	Dynamic programming	No attempts yet	1s	128 MB	Judgeable
Tiling Up BlocksFind the largest subset of blocks that stacks so both knob counts never decrease from bottom to top.	Medium5	Dynamic programmingSorting	No attempts yet	1s	128 MB	Judgeable
Project staffingAssign at most n hired workers to m projects so the total expected profit from rewards, fines, and conditional wages is maximal.	Medium5	Dynamic programmingProbability+1	No attempts yet	1s	128 MB	Judgeable
77377Split a digit string into dictionary words whose telephone-keypad encoding matches each segment.	Medium5	Dynamic programmingTrie+1	No attempts yet	1s	128 MB	Judgeable
Nested Shrubbery BoxesChoose the largest subset of boxes that nest when every box is rotated to fit strictly inside the next box.	Medium5	Dynamic programmingSorting	No attempts yet	1s	128 MB	Judgeable
Family TreesEach person lists two parents, so answer each query with the inherited share one person contributes to another as a reduced fraction, or report no relation.	Medium5	GraphDynamic programming+1	No attempts yet	1s	128 MB	Judgeable
Reconstructing the Longest Common SubsequenceFind the length of the longest common subsequence of two uppercase strings and output the lexicographically smallest one.	Medium5	Dynamic programmingGreedy	No attempts yet	0.1s	256 MB	Judgeable
PointsPick a subset of targets in a row to maximize the total where each picked target scores based on how many neighbors are also picked.	Medium5	Dynamic programming	No attempts yet	3s	128 MB	Judgeable
The Hopeless QueueCount fillings of the movable spots with equal coin totals so every prefix keeps at least as many 50 coins as 100 coins, modulo 1000000.	Medium5	Dynamic programmingCombinatorics	No attempts yet	2s	128 MB	Judgeable
Frozen SprinklersCut pipes with minimum total force so no water flows from the central node to any leaf sprinkler in the tree.	Medium5	Dynamic programmingTree+1	No attempts yet	3s	128 MB	Judgeable
Freeing Up CapacityChoose RAID-1 sets to convert so the gained capacity reaches e GB while the total size of converted sets is minimal.	Medium5	Dynamic programming	No attempts yet	2s	512 MB	Judgeable
Wrestling Team SelectionSplit up to 100 wrestlers into two teams of nearly equal size so the total weights differ as little as possible.	Medium5	Dynamic programming	No attempts yet	1s	128 MB	Judgeable
Prefix-Free SubsetsCount the subsets of the given word set in which no word is a prefix of another word.	Medium5	TrieDynamic programming+1	No attempts yet	1s	128 MB	Judgeable
Minimum Cost SortingFind the cheapest total of moved values needed to sort the array when moving one element to any position costs its value.	Medium5	Dynamic programmingSorting	No attempts yet	1s	128 MB	Judgeable
Cut the ListSplit the list into K consecutive pieces to minimize the sum of each piece's max minus min.	Medium5	Dynamic programmingIntervals	No attempts yet	2s	128 MB	Judgeable
Number of LocksCount length-n strings over heights 1 to 4 that use at least three distinct heights and have an adjacent pair differing by exactly 3.	Medium5	Dynamic programmingCombinatorics	No attempts yet	1s	128 MB	Judgeable
Tutor SimulationChoose a sequence of teaching, training, and book-buying actions within the time limit that maximizes final cash.	Medium5	Dynamic programmingBrute force	No attempts yet	2s	512 MB	Judgeable
InvestChoose one of five products to buy each month, respecting minimum holding periods, to maximize the total resale value at the end.	Medium5	Dynamic programming	No attempts yet	2s	512 MB	Judgeable
HoleFind the side length of the largest all-zero square in an n by n binary grid given by the positions of its ones.	Medium5	Dynamic programmingMatrix	No attempts yet	2s	512 MB	Judgeable
The Umbrella ProblemEach turn the lemming steps one row down while laser beams rotate, and the task asks whether any grass square in the last row is reachable alive.	Medium5	Dynamic programmingSimulation+1	No attempts yet	1s	128 MB	Judgeable
Club ScheduleCount attendance and key-passing schedules over N days where each day's leader attends and the key stays with attendees.	Medium5	Dynamic programmingCombinatorics	No attempts yet	1s	128 MB	Judgeable
Shark TourSteer a car through a grid tunnel with blocked cells to collect the most sharks and print the tie-breaking action sequence.	Medium5	Dynamic programmingMatrix	No attempts yet	1s	256 MB	Judgeable
Heracles and the Stables of AugeasPick rivers whose water totals at least W so the sum of straight-line digging distances from the stable is smallest.	Medium5	Dynamic programmingGeometry	No attempts yet	1s	256 MB	Judgeable
Distinct Subarray GCDsCount the distinct GCD values taken over all contiguous subarrays for each test case.	Medium5	Number theoryDynamic programming+1	No attempts yet	5s	256 MB	Judgeable
EquatorEach test case gives city profits around a circle and asks for the most profitable contiguous block, or zero when all are losses.	Medium5	Dynamic programmingArray	No attempts yet	1s	256 MB	Judgeable
ShopsPick cells with no shared side in an N by 5 profit grid to maximize the summed profit.	Medium5	Dynamic programmingBit manipulation	No attempts yet	2s	256 MB	Judgeable
Chomsky Normal Form GrammarDecide whether a given string of up to 1000 lowercase letters belongs to the language generated from start symbol S by a CNF grammar.	Medium5	Dynamic programmingIntervals	No attempts yet	5s	256 MB	Judgeable
Zeroing a Binary SequenceCount ordered flip sequences of exactly K moves that turn a given binary sequence into all zeroes.	Medium5	CombinatoricsDynamic programming	No attempts yet	1s	256 MB	Judgeable
Restaurant RatingsCount how many nonnegative score sheets rank no better than the given sheet under total sum first and critic order second.	Medium5	CombinatoricsDynamic programming	No attempts yet	1s	256 MB	Judgeable
Travel CardGiven daily bus and train ride counts, compute the cheapest mix of single fares and 1, 7, and 30 day bus and travel passes.	Medium5	Dynamic programmingPrefix sum	No attempts yet	1s	256 MB	Judgeable
Narrow Art GalleryClose exactly k rooms with no row fully closed and no diagonal closures to keep the maximum total value of open rooms.	Medium5	Dynamic programming	No attempts yet	2s	256 MB	Judgeable
A Walk TogetherTwo walkers follow turn-by-turn routes on a grid, and you compute the most blocks they can walk together by waiting and matching identical directed blocks.	Medium5	Dynamic programmingSimulation	No attempts yet	1s	256 MB	Judgeable
Cent SavingsSplit up to 2000 item prices in order into at most d+1 consecutive groups so the sum of each group rounded to the nearest 10 cents is smallest.	Medium5	Dynamic programmingPrefix sum	No attempts yet	5s	512 MB	Judgeable
Super Pipes and Ant FeedingFind the smallest amount of liquid to pour into the root of a tree so percentage splits with optional squaring pipes still meet every leaf demand.	Medium5	Dynamic programmingTree+1	No attempts yet	1s	32 MB	Judgeable