Problems

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Total results29,453 problems

Ricochet Robots
Medium5
BFS, Simulation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Ssari and Bird's Pyramid
Medium5
Math, Prefix sum
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Salary Inequity
Medium5
Segment tree, Tree
No attempts yet
Time limit
10s
Memory limit
256 MB
Judgeable
Top 25 Poll Comparison
Medium5
Greedy, Hash map
No attempts yet
Time limit
10s
Memory limit
256 MB
Judgeable
Wrench Size
Medium5
Math, Brute force
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Burrito King
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Permutation with no spaces
Medium5
Backtracking, Brute force+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Killing Dragons
Medium5
Graph, Greedy
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Super Pipes and Ant Feeding
Medium5
Dynamic programming, Tree+1
No attempts yet
Time limit
1s
Memory limit
32 MB
Judgeable
Magneto Magnets
Medium5
Graph, DFS
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
The One Dollar Gambler
Medium5
Probability, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Breadth-First Search by Foxpower
Medium5
Tree, BFS
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Mushroom tractor
Medium5
Hash map, Math
No attempts yet
Time limit
2s
Memory limit
32 MB
Judgeable
Piggy Back
Medium5
Shortest path, BFS
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Marathon 2
Medium5
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Cow Jog
Medium5
Greedy, Array
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Learning by Example
Medium5
Sorting, Intervals
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Ancient Dictionary Order
Medium5
Topological sort, Graph+1
No attempts yet
Time limit
8s
Memory limit
256 MB
Judgeable
Texas Hold 'em Win Probability
Medium5
Brute force, Implementation
No attempts yet
Time limit
8s
Memory limit
256 MB
Judgeable
Stampede
Medium5
Intervals, Sorting+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Cow Routing
Medium5
Shortest path, Graph
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Meeting Time
Medium5
Dynamic programming, Graph
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Cow Routing II
Medium5
Brute force, Hash map
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Finding the Two Bases
Medium5
Math, Brute force
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Restore Calculation
Medium5
Dynamic programming, Math
No attempts yet
Time limit
8s
Memory limit
512 MB
Judgeable
Nicole
Medium5
Brute force, Bit manipulation+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Arctic Polar Explorer
Medium5
Sorting, Simulation+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Sandcastle
Medium5
BFS, Simulation+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Two-Area Database
Medium5
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
The Light King and the Mirror Maze 1
Medium5
Brute force, Simulation
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
XOR Triples
Medium5
Brute force, Bit manipulation
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Follower of I 1
Medium5
Brute force, Stack+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Censoring
Medium5
String matching, Stack
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Censoring
Medium5
Stack, String matching
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Moocryption
Medium5
Brute force, Matrix+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Pi Day Pie Distribution
Medium5
Dynamic programming, Combinatorics
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Empire
Medium5
Shortest path, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Honey Butter Chip
Medium5
Dynamic programming, Array
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Window
Medium5
Prefix sum, Brute force
No attempts yet
Time limit
8s
Memory limit
256 MB
Judgeable
Color Balls
Medium5
Sorting, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Square Piece Cut
Medium5
Dynamic programming
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Maximize Differences
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Card Game
Medium5
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Cake Corner Trimming
Medium5
Geometry, Math+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Change of Scenery
Medium5
Shortest path, Graph
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Sequence Artisan
Medium5
Greedy, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Travel between two islands
Medium5
Union-find, Math
No attempts yet
Time limit
1s
Memory limit
16 MB
Judgeable
Cactus or not
Medium5
DFS, Graph
No attempts yet
Time limit
1s
Memory limit
32 MB
Judgeable
Great Pow!
Medium5
Number theory, Math
No attempts yet
Time limit
10s
Memory limit
64 MB
Judgeable
Inherited disease
Medium5
Math, Combinatorics
No attempts yet
Time limit
1s
Memory limit
16 MB
Judgeable
Museum wall construction
Medium5
Geometry, Sorting
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Quaternion inverse
Medium5
Number theory, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Uniting Departments
Medium5
Math, Combinatorics
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Pipes
Medium5
DFS, Graph
No attempts yet
Time limit
2s
Memory limit
32 MB
Judgeable
Traveling Salesman Tour 2
Medium5
Dynamic programming, Bit manipulation+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Counting Cafeteria Menus
Medium5
String matching, Array+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Lucky Cookie Bakery
Medium5
Dynamic programming
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
The Hunter
Medium5
Geometry, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Explosive Materials
Medium5
Graph, BFS+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
The Missing Permutation
Medium5
Greedy, Dynamic programming+1
No attempts yet
Time limit
15s
Memory limit
256 MB
Judgeable
Butterfly Ballot
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
The Sorting Hat
Medium5
Bit manipulation, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Attendance Award
Medium5
Dynamic programming, Combinatorics
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Next Unique-Digit Number
Medium5
Backtracking, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Palindrome??
Medium5
String matching, Prefix sum
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Longest Bitonic Subsequence
Medium5
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Criboard Max A
Medium5
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Football scorelines
Medium5
Dynamic programming, Combinatorics
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
All about that base
Medium5
Brute force, Math+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Cantina of Babel
Medium5
Graph, DFS
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Vampire Dice
Medium5
Probability, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
TV War
Medium5
Dynamic programming, Sorting+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Traffic Volume
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Box Betting
Medium5
Prefix sum, Binary search
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Marble Madness
Medium5
Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Robberies
Medium5
Dynamic programming, Probability
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Guarding the Border
Medium5
Binary search, Greedy+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Mobile Gaming
Medium5
Geometry, Intervals+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Combat Odds
Medium5
Probability, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Cross Country Race
Medium5
Simulation, Greedy+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Rotating Penguin Maze
Medium5
BFS, Simulation+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Dimensions
Medium5
Implementation, Hash map+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Krusty's Burger
Medium5
Combinatorics, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Base-2 Palindromes
Medium5
Bit manipulation, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Three Digits
Medium5
Number theory, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Car Game
Medium5
String matching, Array
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Bank Queue
Medium5
Greedy, Heap+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Rock Paper Scissors Lizard Spock
Medium5
Brute force, Math+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Carrot
Medium5
Number theory, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
GCD of Fibonacci Numbers
Medium5
Number theory, Math+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Find the Hidden Word
Medium5
String matching, Trie
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Lineage
Medium5
Sorting, Binary search
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Atomic Computer
Medium5
Dynamic programming, Bit manipulation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Chasing
Medium5
Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Entertainment Box
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Goblin Garden Guards
Medium5
Geometry, Hash map
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Wonowon Numbers
Medium5
Number theory, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Mobile
Medium5
Tree, Math+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Numbers are Easy
Medium5
BFS, Graph+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Matrix
Medium5
Shortest path, Graph
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Ricochet RobotsSlide up to four robots on a grid with walls and use the fewest moves within the given limit to stop robot 1 on the target cell.	Medium5	BFSSimulation	No attempts yet	1s	256 MB	Judgeable
Ssari and Bird's PyramidCount how many times a given letter appears in a requested pyramid row filled by repeating a word in alternating directions.	Medium5	MathPrefix sum	No attempts yet	1s	256 MB	Judgeable
Salary InequitySubtree raises add an amount to every salary below an employee, and each query asks for the max minus min salary in that subtree.	Medium5	Segment treeTree	No attempts yet	10s	256 MB	Judgeable
Top 25 Poll ComparisonSplit two rankings of the same teams into the smallest consecutive groups that hold the same teams and print each size.	Medium5	GreedyHash map	No attempts yet	10s	256 MB	Judgeable
Wrench SizeGiven a printed decimal, find the fraction with the smallest power-of-two denominator that rounds to it by truncation, rounding up, or rounding to nearest.	Medium5	MathBrute force	No attempts yet	5s	256 MB	Judgeable
Burrito KingChoose fractional amounts of capped ingredients to maximize joy without exceeding the unhappiness budget, and print every value as a reduced fraction.	Medium5	GreedySorting+1	No attempts yet	1s	256 MB	Judgeable
Permutation with no spacesRecover the permutation from 1 to N whose decimal forms concatenate to the given digit string, choosing the lexicographically smallest one on ties.	Medium5	BacktrackingBrute force+1	No attempts yet	1s	256 MB	Judgeable
Killing DragonsCompute the smallest number of warriors who move along roads and cut heads faster than dragons regrow them to kill all dragons.	Medium5	GraphGreedy	No attempts yet	2s	256 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
Magneto MagnetsDecide whether all magnets can join into one closed chain with matching polarities at every joint.	Medium5	GraphDFS	No attempts yet	1s	256 MB	Judgeable
The One Dollar GamblerStarting from one dollar, compute the expected capital after T fair coin bets of fraction F and round it to six decimal places.	Medium5	ProbabilityMath	No attempts yet	1s	256 MB	Judgeable
Breadth-First Search by FoxpowerCompute the total distance walked visiting every vertex of a rooted tree in BFS order starting at the root.	Medium5	TreeBFS	No attempts yet	2s	128 MB	Judgeable
Mushroom tractorMushrooms appear one per second, and the goal is the earliest second when some row, column, or diagonal contains at least K of them.	Medium5	Hash mapMath	No attempts yet	2s	32 MB	Judgeable
Piggy BackBessie from field 1 and Elsie from field 2 must both reach the barn at field N, walking alone or meeting in one field to share the rest of the trip.	Medium5	Shortest pathBFS	No attempts yet	1s	256 MB	Judgeable
Marathon 2Run checkpoints 1 to N in order while skipping at most K middle checkpoints to minimize total Manhattan distance.	Medium5	Dynamic programming	No attempts yet	1s	256 MB	Judgeable
Cow JogCount the groups of cows that end at the same position after T minutes when no cow can pass the cow ahead.	Medium5	GreedyArray	No attempts yet	1s	256 MB	Judgeable
Learning by ExampleCount how many integer weights from A to B the nearest-neighbor classifier labels as spotted from N labeled training weights.	Medium5	SortingIntervals	No attempts yet	1s	256 MB	Judgeable
Ancient Dictionary OrderDecide whether some alphabet order makes each given word list sorted lexicographically.	Medium5	Topological sortGraph+1	No attempts yet	8s	256 MB	Judgeable
Texas Hold 'em Win ProbabilityGiven both hole cards and the flop, enumerate all 990 turn and river pairs and report the share where your best five-card hand beats the opponent's.	Medium5	Brute forceImplementation	No attempts yet	8s	256 MB	Judgeable
StampedeCount how many moving segments are ever the closest to the origin while crossing the positive y-axis.	Medium5	IntervalsSorting+1	No attempts yet	1s	256 MB	Judgeable
Cow RoutingFind the cheapest itinerary from city A to city B using ordered routes that charge full price per boarding, breaking ties by fewest flights.	Medium5	Shortest pathGraph	No attempts yet	1s	256 MB	Judgeable
Meeting TimeFind the smallest total travel time that both cows can achieve on separate downhill paths from field 1 to field N.	Medium5	Dynamic programmingGraph	No attempts yet	1s	256 MB	Judgeable
Cow Routing IIFind the cheapest fare from city A to city B using at most two ordered flight routes, paying each used route full fare.	Medium5	Brute forceHash map	No attempts yet	1s	256 MB	Judgeable
Finding the Two BasesFind the two bases between 10 and 15000 where the two given 3-digit sequences represent the same number.	Medium5	MathBrute force	No attempts yet	1s	256 MB	Judgeable
Restore CalculationCount ways to fill each ? in equal-length strings A, B, and C with digits, leading digits nonzero, so A plus B equals C, modulo 1,000,000,007.	Medium5	Dynamic programmingMath	No attempts yet	8s	512 MB	Judgeable
NicolePick at least two locations with no hearing pair among them to maximize total satisfaction.	Medium5	Brute forceBit manipulation+1	No attempts yet	1s	256 MB	Judgeable
Arctic Polar ExplorerWrite an APECODE program that makes a robot with two grippers sort a line of rocks by weight using only balance comparisons.	Medium5	SortingSimulation+2	No attempts yet	1s	256 MB	Judgeable
SandcastleEach wave washes away every sand cell whose empty count among its eight neighbors reaches its firmness, so count the waves until no cell collapses.	Medium5	BFSSimulation+1	No attempts yet	1s	256 MB	Judgeable
Two-Area DatabaseRead a fixed sequence of data kinds using a one-slot cache that loads at cost c and serves hits for free, and minimize total read cost.	Medium5	Dynamic programming	No attempts yet	1s	256 MB	Judgeable
The Light King and the Mirror Maze 1Count assignments to the undecided cells that send a laser entering at border x out through border y.	Medium5	Brute forceSimulation	No attempts yet	2s	256 MB	Judgeable
XOR TriplesChoose the largest subset of 1 to N with no three distinct values xoring to zero, breaking ties by smallest lexicographic order.	Medium5	Brute forceBit manipulation	No attempts yet	5s	256 MB	Judgeable
Follower of I 1Sum, over every distinct ordering of the push, add, and multiply cards, the entries in the top K stack positions after evaluating the RPN process.	Medium5	Brute forceStack+1	No attempts yet	3s	256 MB	Judgeable
CensoringRepeatedly delete the first occurrence of T from S, including matches formed by earlier deletions, and print what remains.	Medium5	String matchingStack	No attempts yet	1s	256 MB	Judgeable
CensoringRepeatedly delete the first occurrence of pattern T from string S until none remains and print the result.	Medium5	StackString matching	No attempts yet	1s	256 MB	Judgeable
MoocryptionFind the substitution cipher with no fixed letters that yields the most MOO strings in all eight grid directions.	Medium5	Brute forceMatrix+1	No attempts yet	1s	256 MB	Judgeable
Pi Day Pie DistributionCount the nondecreasing distributions of n pie pieces among k people with each person getting at least one piece.	Medium5	Dynamic programmingCombinatorics	No attempts yet	1s	256 MB	Judgeable
EmpireFind the fastest route from A to B whose total hull damage stays strictly below K.	Medium5	Shortest pathDynamic programming	No attempts yet	1s	256 MB	Judgeable
Honey Butter ChipArrange the M extra bags within the N fixed bags and pick no two adjacent bags to maximize the chip total.	Medium5	Dynamic programmingArray	No attempts yet	5s	256 MB	Judgeable
WindowFind the largest interior grid-aligned square whose border runs only along domino edges and report its size and top-left corner.	Medium5	Prefix sumBrute force	No attempts yet	8s	256 MB	Judgeable
Color BallsFor each ball, add up the sizes of all strictly smaller balls with a different color.	Medium5	SortingPrefix sum+1	No attempts yet	1s	256 MB	Judgeable
Square Piece CutCut an n by m integer-sided rectangle with guillotine cuts into the fewest integer-sided squares.	Medium5	Dynamic programming	No attempts yet	2s	256 MB	Judgeable
Maximize DifferencesReorder the given array so the sum of absolute differences between neighbors is as large as possible.	Medium5	GreedySorting+1	No attempts yet	1s	256 MB	Judgeable
Card GameTwo piles of N cards are compared from the top, and the program finds the largest score earned by discarding a smaller right card.	Medium5	Dynamic programming	No attempts yet	1s	256 MB	Judgeable
Cake Corner TrimmingChoose the largest corner-trim parameter s so the convex polygon keeps at most fraction a of its area.	Medium5	GeometryMath+1	No attempts yet	1s	256 MB	Judgeable
Change of SceneryDecide whether a second shortest route from junction 1 to N exists that differs from the given one by at least one street.	Medium5	Shortest pathGraph	No attempts yet	3s	256 MB	Judgeable
Sequence ArtisanFind the largest product of any contiguous block in an array with values from -2 to 2, then report it modulo 1000000007.	Medium5	GreedyDynamic programming+1	No attempts yet	1s	256 MB	Judgeable
Travel between two islandsAfter each bridge joins two neighboring islands, report how many island pairs are mutually reachable and the total bridge crossings summed over those pairs.	Medium5	Union-findMath	No attempts yet	1s	16 MB	Judgeable
Cactus or notDecide whether a connected undirected graph is a cactus where each vertex lies on at most one simple cycle.	Medium5	DFSGraph	No attempts yet	1s	32 MB	Judgeable
Great Pow!Compute the tower of k+1 copies of a modulo a+1, where a is minus one so only the parity of the upper tower matters.	Medium5	Number theoryMath	No attempts yet	10s	64 MB	Judgeable
Inherited diseaseFollow the birth-order path down D generations where a generation g member has g+1 children and print each breadth-first number modulo 1000000007.	Medium5	MathCombinatorics	No attempts yet	1s	16 MB	Judgeable
Museum wall constructionFind the shortest closed curve enclosing N disjoint equal circles of radius R.	Medium5	GeometrySorting	No attempts yet	1s	256 MB	Judgeable
Quaternion inverseGiven a prime M and up to 100000 quaternions with components modulo M, output the modular inverse of each or zeros if none exists.	Medium5	Number theoryMath	No attempts yet	1s	256 MB	Judgeable
Uniting DepartmentsMerge departments pairwise at product-of-sizes cost and report the total cost and the number of ordered merge sequences modulo 1000000007.	Medium5	MathCombinatorics	No attempts yet	1s	256 MB	Judgeable
PipesFind every pipe whose removal disconnects the spring network and print them sorted by endpoint numbers.	Medium5	DFSGraph	No attempts yet	2s	32 MB	Judgeable
Traveling Salesman Tour 2Find the cheapest tour that starts at one city, visits each of N cities exactly once, and returns to the start using the given directed costs.	Medium5	Dynamic programmingBit manipulation+1	No attempts yet	2s	256 MB	Judgeable
Counting Cafeteria MenusCount how many distinct dish sets appear when the current set of N out of M dishes shifts forward by one each meal.	Medium5	String matchingArray+1	No attempts yet	2s	256 MB	Judgeable
Lucky Cookie BakeryAssign each dough ball to one of two ovens with different baking times to minimize the time the slower oven finishes.	Medium5	Dynamic programming	No attempts yet	5s	128 MB	Judgeable
The HunterFind the shortest rope between two points outside a circle that never enters it, straight when clear and two tangents joined by an arc otherwise.	Medium5	GeometryMath	No attempts yet	1s	128 MB	Judgeable
Explosive MaterialsSplit conflicting materials into two safe boxes and minimize the fuller box size.	Medium5	GraphBFS+1	No attempts yet	3s	256 MB	Judgeable
The Missing PermutationFill the zeros with the missing values to maximize the length of the longest increasing subsequence.	Medium5	GreedyDynamic programming+1	No attempts yet	15s	256 MB	Judgeable
Butterfly BallotDecide whether the candidates can be ordered so candidate 1 finishes first when half of each ballot position's supporters spill to the next position.	Medium5	GreedySorting+1	No attempts yet	1s	256 MB	Judgeable
The Sorting HatFind the department of student n by counting the set bits in n-1 and taking the remainder modulo p.	Medium5	Bit manipulationMath	No attempts yet	1s	256 MB	Judgeable
Attendance AwardCount length-N strings over L, O and A with at most one L and no three consecutive As for each N up to 3000.	Medium5	Dynamic programmingCombinatorics	No attempts yet	1s	256 MB	Judgeable
Next Unique-Digit NumberFind the smallest integer above N that uses no zero and repeats none of the digits 1 to 9, printing 0 when none exists.	Medium5	BacktrackingCombinatorics+1	No attempts yet	1s	256 MB	Judgeable
Palindrome??Answer up to a million queries asking whether a subarray of the given number sequence reads the same forward and backward.	Medium5	String matchingPrefix sum	No attempts yet	1s	256 MB	Judgeable
Longest Bitonic SubsequenceGiven a sequence of up to 1000 numbers, find the length of its longest subsequence that strictly rises then strictly falls.	Medium5	Dynamic programming	No attempts yet	1s	256 MB	Judgeable
Criboard Max APress A, select all, copy, and paste within N keystrokes to show the most As possible.	Medium5	Dynamic programming	No attempts yet	1s	256 MB	Judgeable
Football scorelinesCount the ordered scoring sequences by both teams that reach the given final score under the listed play values, modulo 1000000009.	Medium5	Dynamic programmingCombinatorics	No attempts yet	2s	256 MB	Judgeable
All about that baseTest every base from 1 to 36 and list the bases where the given addition, subtraction, multiplication, or division holds.	Medium5	Brute forceMath+1	No attempts yet	2s	256 MB	Judgeable
Cantina of BabelGiven each character's spoken and understood languages, remove as few characters as possible so every remaining pair can exchange messages through translators.	Medium5	GraphDFS	No attempts yet	2s	256 MB	Judgeable
Vampire DiceCompute the success probability of scoring at least y points from x exploding ten-sided dice where 8 to 10 score and 10 grants an extra roll.	Medium5	ProbabilityDynamic programming	No attempts yet	1s	256 MB	Judgeable
TV WarPick non-overlapping weekly TV programs to maximize the total preference score.	Medium5	Dynamic programmingSorting+2	No attempts yet	1s	256 MB	Judgeable
Traffic VolumeCount how many cars came from the left from the unordered times in two boxes with offsets of 500, 1000, and 1500.	Medium5	GreedySorting+1	No attempts yet	1s	256 MB	Judgeable
Box BettingThe driver picks a random contiguous run of boxes, and the program reports how often its item sum lands below L, within L to U, or above U.	Medium5	Prefix sumBinary search	No attempts yet	1s	256 MB	Judgeable
Marble MadnessGiven starting counts of black and white marbles and the two-draw replacement rules, print the probability the last remaining marble is black or white.	Medium5	Math	No attempts yet	1s	256 MB	Judgeable
RobberiesPick a subset of banks that maximizes the stolen money while the combined capture probability stays strictly below the given limit.	Medium5	Dynamic programmingProbability	No attempts yet	1s	256 MB	Judgeable
Guarding the BorderAdd up to M towers anywhere on a circular border of length L so the largest gap between neighboring towers is as small as possible.	Medium5	Binary searchGreedy+1	No attempts yet	3s	256 MB	Judgeable
Mobile GamingTwo rectangles move at constant speed from time 0 to 1; report the first moment they touch or overlap, or report no collision.	Medium5	GeometryIntervals+1	No attempts yet	1s	256 MB	Judgeable
Combat OddsGiven N independent battles with win chance p, compute the chance that a losing run of at least L occurs.	Medium5	ProbabilityDynamic programming	No attempts yet	1s	256 MB	Judgeable
Cross Country RaceRunners start one minute apart and stick together once a chaser catches the runner ahead, and the task asks how many repeat races the grouped runners need.	Medium5	SimulationGreedy+1	No attempts yet	1s	256 MB	Judgeable
Rotating Penguin MazePrint the compass moves that walk the penguin along the single maze path while each pressure plate rotates the maze 90 degrees.	Medium5	BFSSimulation+1	No attempts yet	1s	256 MB	Judgeable
DimensionsConvert defined units and evaluate each expression, printing results in SI base units or Incompatible for mismatched dimensions.	Medium5	ImplementationHash map+1	No attempts yet	1s	256 MB	Judgeable
Krusty's BurgerCount burger combinations of size, bun, cheeses, toppings and sauces whose size plus extra-item cost is at most B.	Medium5	CombinatoricsMath	No attempts yet	1s	256 MB	Judgeable
Base-2 PalindromesFind the M-th positive integer whose binary representation reads the same forward and backward and print it in decimal.	Medium5	Bit manipulationMath	No attempts yet	1s	256 MB	Judgeable
Three DigitsGiven n up to 10^7, print the last three digits of n! after removing every trailing zero, keeping leading zeros.	Medium5	Number theoryMath	No attempts yet	1s	256 MB	Judgeable
Car GameFind the first dictionary word that contains each three-letter plate as a subsequence, or report that none exists.	Medium5	String matchingArray	No attempts yet	2s	256 MB	Judgeable
Bank QueuePick at most one person per minute before each deadline to maximize the total cash collected.	Medium5	GreedyHeap+1	No attempts yet	1s	256 MB	Judgeable
Rock Paper Scissors Lizard SpockLeo recovers the computer's hidden move generator from n observed throws and prints the winning reply to each of the next m throws.	Medium5	Brute forceMath+1	No attempts yet	1s	256 MB	Judgeable
CarrotFor each N, count the steps to reach zero by subtracting one when the pile splits into equal piles of at least two and subtracting two otherwise.	Medium5	Number theoryDynamic programming	No attempts yet	1s	256 MB	Judgeable
GCD of Fibonacci NumbersCompute the greatest common divisor of the Nth and Mth Fibonacci numbers and print it modulo 1000000007.	Medium5	Number theoryMath+1	No attempts yet	1s	256 MB	Judgeable
Find the Hidden WordGiven a list of known words and several messages, find which listed words occur as substrings in each message and report NO, the unique word, or AMBIGUOUS.	Medium5	String matchingTrie	No attempts yet	1s	256 MB	Judgeable
LineagePick a father and a mother from the given gene values so the nearest of the three pups' gene values to R is as close as possible.	Medium5	SortingBinary search	No attempts yet	1s	256 MB	Judgeable
Atomic ComputerCount the length-y signed-binary strings over -1, 0 and 1 whose digits weighted by powers of two sum to x.	Medium5	Dynamic programmingBit manipulation	No attempts yet	1s	256 MB	Judgeable
ChasingCompute how many turns pass until a tortoise moving one section per turn and a hare moving two meet on a circular track.	Medium5	Math	No attempts yet	1s	256 MB	Judgeable
Entertainment BoxSchedule the most TV shows on k recorders so no recorder tapes overlapping shows.	Medium5	GreedySorting+1	No attempts yet	2s	256 MB	Judgeable
Goblin Garden GuardsCount how many of up to 100000 points remain uncovered by 20000 sprinkler circles of radius at most 100.	Medium5	GeometryHash map	No attempts yet	3s	256 MB	Judgeable
Wonowon NumbersCount primes p up to n, except 2 and 5, whose smallest alternating one-zero multiple starting and ending with 1 has exactly p minus 2 digits.	Medium5	Number theoryMath	No attempts yet	1s	256 MB	Judgeable
MobileGiven a tree of balanced arms with arm-length ratios, compute the minimum total weight when all weights are integers and one weight has a lower bound.	Medium5	TreeMath+1	No attempts yet	1s	256 MB	Judgeable
Numbers are EasyFind the smallest positive multiple of N whose decimal digits are only 0 and 1 for each test case.	Medium5	BFSGraph+1	No attempts yet	1s	256 MB	Judgeable
MatrixCompute each agent's earliest arrival time, then find Neo's shortest safe route to a telephone that beats every agent there.	Medium5	Shortest pathGraph	No attempts yet	2s	256 MB	Judgeable