Problems

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Total results29,463 problems

CDVII
Medium4
Simulation, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Australian Voting
Medium4
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Crypt Kicker II
Medium4
String, Hash map+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Contest Scoreboard
Medium4
Implementation, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Poker Hands
Medium4
Implementation, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Is Bigger Smarter?
Medium4
Dynamic programming, Sorting
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Status is Not Quo
Medium4
Simulation, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
A Smart Brain is a Tasty Brain
Medium4
String, Stack+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Let the Wookiee Win!
Medium4
Implementation, Brute force+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The History of the Sith Rulers
Medium4
Sorting, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Is the Kid in Green Zelda?
Medium4
Graph, Shortest path+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Symbolic Logic Mechanization
Medium4
String, Recursion+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
PropBot
Medium4
Brute force, Geometry+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
“Ancient” Calculator
Medium4
Brute force, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
This Is Halloween: Saving Money
Medium4
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Wandering Aimlessly
Medium4
Simulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tribute (Editor)
Medium4
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Repeated Rounding
Medium4
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Artificial Strife
Medium4
Simulation, Array+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Relative Relatives
Medium4
Tree, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Jugglefest
Medium4
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Grade School Multiplication
Medium4
String, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sokoban
Medium4
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Image Compression
Medium4
Divide and conquer, Recursion+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
DuLL
Medium4
Simulation, Bit manipulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Persistent Bits
Medium4
Bit manipulation, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Here We Go(relians) Again
Medium4
Graph, Shortest path+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Electronic Document Security
Medium4
Implementation, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Linear Pachinko
Medium4
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Frugal Search
Medium4
String, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Root
Medium4
Binary search, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Pascal's Travels
Medium4
Dynamic programming, Array+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Gargle
Medium4
Math, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Treadmill
Medium4
Implementation, String matching+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Programmer, Rank Thyself
Medium4
Sorting, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Jungle Roads
Medium4
Minimum spanning tree, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Image Perimeters
Medium4
BFS, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Colorville
Medium4
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Instruens Fabulam
Medium4
String, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Myacm Triangles
Medium4
Brute force, Geometry+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Automatic Editing
Medium4
String, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Robot Motion
Medium4
Simulation, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Finding Rectangles
Medium4
Brute force, Geometry+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Oil Deposits
Medium4
Graph, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Mapmaker
Medium4
Array, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Equation Elation
Medium4
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Perfect Cubes
Medium4
Brute force, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
DNA Translation
Medium4
String, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Letter Sequence Analysis
Medium4
String, Hash map+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Forays into Anti-Aliased ASCII Art
Medium4
Implementation, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Underground Cables
Medium4
Minimum spanning tree, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Witness Redaction Plan
Medium4
String, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bulls and Cows
Medium4
Brute force, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Shrew-ology
Medium4
Brute force, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Balanced Budget Initiative
Medium4
Hash map, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Nine
Medium4
Brute force, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Robot Navigation
Medium4
BFS, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
User Names
Medium4
String, Hash map+2
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Ropes
Medium4
Simulation, Greedy+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Portfolio Rebalancing
Medium4
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tree Grafting
Medium4
Tree, Stack+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Baseball
Medium4
Simulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Set-Theoretic Number Notation
Medium4
String, Recursion+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Baskets of Gold Coins
Medium4
Math, Brute force+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Winter Festival
Medium4
Graph, DFS+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Paint Mix
Medium4
Simulation, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Suit Distribution
Medium4
Combinatorics, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Shortest Prefixes
Medium4
Trie, String+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Blackjack
Medium4
Math, Combinatorics+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Shake, Rattle and Roll
Medium4
Simulation, Matrix+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Compress
Medium4
String, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Spreadsheet Circular Reference
Medium4
Graph, DFS+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Triangle Graph
Medium4
Dynamic programming, Graph
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Stable String
Medium4
Stack, Greedy+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tiles of Tetris, NOT!
Medium4
Math, Number theory
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Not So Flat After All
Medium4
Number theory, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Stock Chase
Medium4
Union-find, Graph
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Musical Chairs
Medium4
Math, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
A Day at the Races
Medium4
Simulation, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
A Tale from the Dark Side of the Moon
Medium4
String, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Fermat's Christmas Theorem
Medium4
Number theory, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Wooden Blocks
Medium4
Implementation, String+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Flatten the Expression
Medium4
String, Recursion+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Still Johnny Can't Add
Medium4
Array, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
It's All About Three
Medium4
Number theory, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bertrand's Postulate
Medium4
Number theory, Math+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Pablo Squarson's Headache
Medium4
Simulation, Array+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Amazing Mazes
Medium4
BFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Next Mayor
Medium4
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Ohga's Fortune
Medium4
Simulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Elevator
Medium4
BFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Money Matters
Medium4
Union-find, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Phone List
Medium4
Trie, String+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Web Pages
Medium4
Stack, String+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Maps
Medium4
Brute force, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Discounts
Medium4
Dynamic programming, Greedy+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Matrix Powers
Medium4
Matrix, Divide and conquer+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Armageddon
Medium4
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Preventing Paradoxes
Medium4
Geometry, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Geologic Strata
Medium4
Implementation, Matrix+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
CDVIIPair each vehicle's enter records with the immediately following exit, charge per-kilometre tolls by start hour plus fees, and print sorted totals in dollars.	Medium4	SimulationSorting+2	No attempts yet	1s	128 MB	Judgeable
Australian VotingSimulate multi-round preferential voting: eliminate the lowest candidates each round and transfer their ballots until someone exceeds 50% or a tie remains.	Medium4	SimulationImplementation+2	No attempts yet	1s	128 MB	Judgeable
Crypt Kicker IIOne input line is the pangram 'the quick brown fox jumps over the lazy dog' encrypted by a letter substitution; find it, build the table, and decrypt every line.	Medium4	StringHash map+2	No attempts yet	1s	128 MB	Judgeable
Contest ScoreboardGiven judging queue entries, compute each contestant's solved count and penalty time, then print the standings in rank order.	Medium4	ImplementationSorting+2	No attempts yet	1s	128 MB	Judgeable
Poker HandsCompare two five-card poker hands and decide which ranks higher, handling all standard categories and tie-breaks.	Medium4	ImplementationSorting+1	No attempts yet	1s	128 MB	Judgeable
Is Bigger Smarter?Given pairs of weight and IQ for up to 1000 elephants, find the largest subset whose weights strictly increase while IQs strictly decrease.	Medium4	Dynamic programmingSorting	No attempts yet	1s	128 MB	Judgeable
The Status is Not QuoGiven circuit board squares with wired connection points, trace each exterior start point to the exterior point where its wire path ends.	Medium4	SimulationGraph+1	No attempts yet	1s	128 MB	Judgeable
A Smart Brain is a Tasty BrainParse each of up to 10000 Boolean expressions, evaluate it, and report whether the brain's given answer matches.	Medium4	StringStack+2	No attempts yet	1s	128 MB	Judgeable
Let the Wookiee Win!On a 5x5 board, find the single empty square where playing O neither makes four O in a row nor blocks any of X's winning squares.	Medium4	ImplementationBrute force+2	No attempts yet	1s	128 MB	Judgeable
The History of the Sith RulersGiven up to 50 rulers with the start and end months of each reign, report which rulers held power during each queried year, in order.	Medium4	SortingImplementation+2	No attempts yet	1s	128 MB	Judgeable
Is the Kid in Green Zelda?Find the minimum total cost path from the top-left to the bottom-right cell of an N x N grid where each cell's value is paid when visited.	Medium4	GraphShortest path+2	No attempts yet	1s	256 MB	Judgeable
Symbolic Logic MechanizationParse a prefix logic formula, report the first syntax error left to right, then classify it as a tautology, contradiction, or contingent.	Medium4	StringRecursion+2	No attempts yet	1s	128 MB	Judgeable
PropBotGiven at most 24 seconds, each spent moving 10 cm forward or turning 45 degrees right, find the closest reachable point to a target and print its distance to six decimals.	Medium4	Brute forceGeometry+2	No attempts yet	1s	128 MB	Judgeable
“Ancient” CalculatorCount expressions a Op b = c on a three-digit seven-segment display whose segment currents match the three given readings.	Medium4	Brute forceImplementation+2	No attempts yet	1s	128 MB	Judgeable
This Is Halloween: Saving MoneyFor each box, compute the exact wrapping paper area from its dimensions and truncate the result to a given number of significant digits.	Medium4	MathImplementation+2	No attempts yet	1s	128 MB	Judgeable
Wandering AimlesslySimulate NPC movement scripts on a grid, converting blocked steps into pauses, looping or reversing scripts, and print the map after T turns.	Medium4	SimulationImplementation+1	No attempts yet	1s	128 MB	Judgeable
Tribute (Editor)Simulate a buggy modal editor: given keystrokes, apply insert, delete, duplicate, reverse, and cursor commands, then print the buffer with a caret marking the cursor position.	Medium4	SimulationImplementation+2	No attempts yet	1s	128 MB	Judgeable
Repeated RoundingRound each integer repeatedly at increasing place values (ones, tens, hundreds, ...) using round-half-up until the value no longer exceeds the current threshold.	Medium4	MathImplementation+1	No attempts yet	1s	128 MB	Judgeable
Artificial StrifeSimulate multiple Game of Life rule sets on one grid for T turns, resolving collisions alphabetically, and report each species' maximum and minimum population.	Medium4	SimulationArray+1	No attempts yet	1s	128 MB	Judgeable
Relative RelativesGiven Ted's age of 100 and each descendant's father name plus the father's age at the child's birth, compute every descendant's age and list them oldest first, ties broken by name.	Medium4	TreeDFS+2	No attempts yet	1s	128 MB	Judgeable
JugglefestSimulate the first 20 throws of a siteswap pattern, assigning balls in order of first use, and detect any time two balls are due on the same throw.	Medium4	SimulationImplementation+2	No attempts yet	1s	128 MB	Judgeable
Grade School MultiplicationFormat a grade-school multiplication display column by column, handling zero digits in the second operand and single-line answers.	Medium4	StringSimulation+2	No attempts yet	1s	128 MB	Judgeable
SokobanGiven a Sokoban board and a sequence of key presses, simulate the game and print the final board and whether all boxes reached goals.	Medium4	SimulationImplementation	No attempts yet	1s	128 MB	Judgeable
Image CompressionCompress a binary square bitmap with a quadtree and a majority threshold, then output the image the encoding reconstructs.	Medium4	Divide and conquerRecursion+2	No attempts yet	1s	128 MB	Judgeable
DuLLGiven program sizes, DLL sizes, and a sequence of program start and exit events, find the peak memory use including loaded DLLs.	Medium4	SimulationBit manipulation+1	No attempts yet	1s	128 MB	Judgeable
Persistent BitsStarting from a seed S, repeatedly apply (A*X+B) mod C and report, for each of the 16 bit positions, whether it is always 1, always 0, or varies.	Medium4	Bit manipulationSimulation+1	No attempts yet	1s	128 MB	Judgeable
Here We Go(relians) AgainFind the shortest travel time across a grid of streets with posted integer speeds, one-way rules, and closed roads.	Medium4	GraphShortest path+2	No attempts yet	1s	128 MB	Judgeable
Electronic Document SecurityProcess a log of ACL +, -, = entries in order and print the final rights for each entity, merging entities with identical rights.	Medium4	ImplementationSimulation+2	No attempts yet	1s	128 MB	Judgeable
Linear PachinkoFor each linear Pachinko string, compute the percentage chance that a ball dropped on a uniformly random character exits through a hole or off an end, truncated to an integer.	Medium4	SimulationImplementation+2	No attempts yet	1s	128 MB	Judgeable
Frugal SearchGiven a word list and queries of bar-separated terms with unsigned, plus, and minus letters, output the lexicographically smallest matching word or NONE for each query.	Medium4	StringImplementation+2	No attempts yet	1s	128 MB	Judgeable
RootFor each pair B and N, find the positive integer A that makes A^N as close to B as possible.	Medium4	Binary searchMath+2	No attempts yet	1s	128 MB	Judgeable
Pascal's TravelsCount paths on an n by n digit board from top-left to bottom-right, where each square's digit sets the exact right or down step length.	Medium4	Dynamic programmingArray+2	No attempts yet	1s	128 MB	Judgeable
GarglePrint base-7 digits of N/D from position B through E after the radix point, with leading zeros preserved.	Medium4	MathSimulation+1	No attempts yet	1s	128 MB	Judgeable
TreadmillScan a sample stream for chirp bit patterns and decode each chirp's speed and inclination, printing its start time.	Medium4	ImplementationString matching+1	No attempts yet	1s	128 MB	Judgeable
Programmer, Rank ThyselfRank teams by problems solved, total time, and rounded geometric mean, then print aligned result tables.	Medium4	SortingMath+2	No attempts yet	1s	128 MB	Judgeable
Jungle RoadsGiven a connected weighted graph of villages and roads, find the minimum total maintenance cost of a set of roads that keeps every village connected.	Medium4	Minimum spanning treeGraph+2	No attempts yet	1s	128 MB	Judgeable
Image PerimetersGiven a grid and a click, find all X squares connected to the click by 8-direction adjacency and report the perimeter of that object.	Medium4	BFSDFS+2	No attempts yet	1s	128 MB	Judgeable
ColorvilleSimulate players advancing on a colored board by drawing cards, and report who wins or that the deck ran out.	Medium4	SimulationImplementation+2	No attempts yet	1s	128 MB	Judgeable
Instruens FabulamRead a header specifying each column's alignment, then print each table with borders, sized columns, and aligned cells.	Medium4	StringImplementation+2	No attempts yet	1s	128 MB	Judgeable
Myacm TrianglesAmong 4 to 15 labeled points, find the triangle with the largest area that contains no other point inside or on its edges.	Medium4	Brute forceGeometry+2	No attempts yet	1s	128 MB	Judgeable
Automatic EditingApply a fixed list of find-and-replace rules in order, repeatedly replacing the first occurrence of each find string until it no longer appears, and print the final text.	Medium4	StringSimulation+2	No attempts yet	1s	128 MB	Judgeable
Robot MotionSimulate a robot walking a grid of N/S/E/W arrows from a given top column, and report either the steps to exit or the steps before a loop plus its length.	Medium4	SimulationGraph+1	No attempts yet	1s	128 MB	Judgeable
Finding RectanglesList every axis-aligned rectangle that can be formed from up to 26 labeled points, printing the four vertex labels in clockwise order.	Medium4	Brute forceGeometry+2	No attempts yet	1s	128 MB	Judgeable
Oil DepositsCount connected components of oil pockets (@) in a grid where cells connect in all eight directions; input ends when m is 0.	Medium4	GraphDFS+2	No attempts yet	1s	128 MB	Judgeable
MapmakerGiven array declarations with bounds and element sizes, compute each reference's physical address with the row-major address formula.	Medium4	ArrayMath+2	No attempts yet	1s	128 MB	Judgeable
Equation ElationRepeatedly reduce an arithmetic expression on the left of an equals sign by performing one operation at a time in precedence order, printing each intermediate line.	Medium4	SimulationImplementation+2	No attempts yet	1s	128 MB	Judgeable
Perfect CubesFind all quadruples a, b, c, d with 2 <= a <= N, b < c < d, and a^3 = b^3 + c^3 + d^3, printed in sorted order.	Medium4	Brute forceMath+2	No attempts yet	1s	128 MB	Judgeable
DNA TranslationFor each DNA strand, try all four readings (forward, reverse, complement, reverse complement), translate the first AUG to the first stop codon, and print the lexicographically greatest valid protein or a failure message.	Medium4	StringSimulation+2	No attempts yet	1s	128 MB	Judgeable
Letter Sequence AnalysisRead a text block to EOF and, for each sequence length 1 to 5, list the five most frequent letter sequences with alphabetized ties.	Medium4	StringHash map+2	No attempts yet	1s	128 MB	Judgeable
Forays into Anti-Aliased ASCII ArtFor each line y = mx + b, shade two pixels per integer x by fractional part, round gray levels to tenths, and print a 20x20 character plot.	Medium4	ImplementationSimulation+1	No attempts yet	1s	128 MB	Judgeable
Underground CablesGiven up to 1000 points, connect them all with straight line segments of minimum total length, with no two segments crossing.	Medium4	Minimum spanning treeGraph+2	No attempts yet	1s	128 MB	Judgeable
Witness Redaction PlanReplace every character of each sentence that contains a sensitive word (case-insensitive) with @, keeping the rest of the message unchanged.	Medium4	StringImplementation+1	No attempts yet	1s	128 MB	Judgeable
Bulls and CowsGiven a transcript of Bulls and Cows guesses and replies for codes of length up to 7 with distinct digits, count the codes consistent with all replies and print the smallest one.	Medium4	Brute forceImplementation	No attempts yet	1s	128 MB	Judgeable
Shrew-ologyGiven per-trait dominance rules and adult shrews with sex and trait bits, list every mother-father pair that could produce each juvenile.	Medium4	Brute forceImplementation+2	No attempts yet	1s	128 MB	Judgeable
Balanced Budget InitiativeReconcile a checkbook register against a bank statement, flagging missing, repeated, mis-copied, and miscalculated entries.	Medium4	Hash mapSimulation+1	No attempts yet	1s	128 MB	Judgeable
NineFor each desired microwave time, pick the four-digit MM:SS entry with the most 9s, then the least error under 10%, then lexicographically smallest.	Medium4	Brute forceImplementation+2	No attempts yet	1s	128 MB	Judgeable
Robot NavigationFind the length of the shortest command program that walks a robot from start to destination with turns and moves, and count distinct shortest programs modulo m.	Medium4	BFSGraph+1	No attempts yet	1s	128 MB	Judgeable
User NamesGenerate unique lowercase user names from full names using fixed truncation and numeric suffix collision rules, printing each result.	Medium4	StringHash map+2	No attempts yet	3s	256 MB	Judgeable
RopesGiven pitch lengths of a climb, compute the maximum number of climbers for 50, 60, and 70 meter ropes, or 0 if a rope is unsuitable.	Medium4	SimulationGreedy+2	No attempts yet	1s	128 MB	Judgeable
Portfolio RebalancingSimulate each term's fixed fee, percentage fee, and return per instrument, pool and redistribute every NREBALANCE terms, and print each ending balance to two decimals.	Medium4	SimulationImplementation+2	No attempts yet	1s	128 MB	Judgeable
Tree GraftingGiven a depth-first traversal string of an ordered tree, report its height and the height after converting it to a left-child/right-sibling binary tree.	Medium4	TreeStack+2	No attempts yet	1s	128 MB	Judgeable
BaseballSimulate one or more full baseball games, including a linear congruential generator for hits and sacrifices, and print every hit, run, and final team totals.	Medium4	SimulationImplementation+1	No attempts yet	1s	128 MB	Judgeable
Set-Theoretic Number NotationParse two numbers given as von Neumann ordinal sets, add their values, and print the sum in the same nested-brace notation.	Medium4	StringRecursion+1	No attempts yet	1s	128 MB	Judgeable
Baskets of Gold CoinsGiven the total weight of coins drawn with counts 1..N-1 from N baskets, find which basket holds the lighter coins.	Medium4	MathBrute force+2	No attempts yet	1s	128 MB	Judgeable
Winter FestivalGiven each person's single gift recipient, print every giving cycle in the order their first names appear in the input.	Medium4	GraphDFS+1	No attempts yet	1s	128 MB	Judgeable
Paint MixFor each test case, find how many mix iterations make the black-to-white ratio in both pails within 0.00001 of B/W.	Medium4	SimulationMath	No attempts yet	1s	128 MB	Judgeable
Suit DistributionFor each pair (a, b), compute the probability that the opponents' a+b cards of one suit split a and b between them.	Medium4	CombinatoricsMath+2	No attempts yet	1s	128 MB	Judgeable
Shortest PrefixesFor each word in a list, find the shortest prefix that matches only that word, counting an exact match as unique even if longer words share it.	Medium4	TrieString+2	No attempts yet	1s	128 MB	Judgeable
BlackjackGiven n decks and three visible cards, compute the probability that the player's two-card hand beats the dealer's two-card hand.	Medium4	MathCombinatorics+2	No attempts yet	1s	128 MB	Judgeable
Shake, Rattle and RollFill a square grid with an uppercase message plus padding letters, then apply the key's sequence of shake, rattle, and roll operations and print the final flat string.	Medium4	SimulationMatrix+2	No attempts yet	1s	128 MB	Judgeable
CompressGiven pairs F and R with F < R, print F and the shortest compressed form C that decodes back to R.	Medium4	StringImplementation+1	No attempts yet	1s	128 MB	Judgeable
Spreadsheet Circular ReferenceGiven spreadsheet cell formulas as lines, decide for each defined cell whether evaluating it leads to a circular reference, printing the cell name and circular or ok.	Medium4	GraphDFS+1	No attempts yet	1s	128 MB	Judgeable
Triangle GraphFind the minimum vertex-cost path from top-center to bottom-center in a layered 3-column DAG over N rows.	Medium4	Dynamic programmingGraph	No attempts yet	1s	256 MB	Judgeable
Stable StringGiven a string of braces, find the minimum number of single-character flips that make all brackets correctly balanced.	Medium4	StackGreedy+2	No attempts yet	1s	128 MB	Judgeable
Tiles of Tetris, NOT!Given a tile of width W and height H in fixed orientation, find the smallest square it can tile and count the tiles needed.	Medium4	MathNumber theory	No attempts yet	1s	128 MB	Judgeable
Not So Flat After AllFor each pair of positive integers, find the smallest prime set covering both numbers and the Manhattan distance between their exponent vectors.	Medium4	Number theoryMath+1	No attempts yet	1s	128 MB	Judgeable
Stock ChaseGiven share-purchase transactions between companies in order, count how many must be rejected because they would create a cycle.	Medium4	Union-findGraph	No attempts yet	1s	128 MB	Judgeable
Musical ChairsGiven N children in a circle and a step D, repeatedly remove the D-th child counting around the circle; report the last child left plus N and D.	Medium4	MathSimulation+2	No attempts yet	1s	128 MB	Judgeable
A Day at the RacesRead a season of Grand Prix results and print final standings for drivers and teams, breaking ties by countback and then lexicographically.	Medium4	SimulationSorting+2	No attempts yet	1s	128 MB	Judgeable
A Tale from the Dark Side of the MoonReimplement a lost text filter that applies four ordered string rules per line, including conditional ei to ie and dd to p replacements, stopping at a line reading EOF.	Medium4	StringImplementation+2	No attempts yet	1s	128 MB	Judgeable
Fermat's Christmas TheoremFor each query interval, count the primes in it and how many of those satisfy the sum-of-two-squares criterion.	Medium4	Number theoryMath	No attempts yet	1s	128 MB	Judgeable
Wooden BlocksGiven a string of digit pieces, check whether it forms a valid interlocking arrangement starting with piece 1, ending with piece 2, and matching every adjacent edge pair.	Medium4	ImplementationString+2	No attempts yet	1s	128 MB	Judgeable
Flatten the ExpressionParse a recursively repeated bracketed expression and print its flattened string without spaces.	Medium4	StringRecursion+1	No attempts yet	1s	128 MB	Judgeable
Still Johnny Can't AddDecide whether an N by N grid can be written as row label plus column label for all cells, up to N=10.	Medium4	ArrayMath+2	No attempts yet	1s	128 MB	Judgeable
It's All About ThreeFor each input number, decide whether every prime factor ends in the digit 3.	Medium4	Number theoryMath+1	No attempts yet	1s	128 MB	Judgeable
Bertrand's PostulateFor each n until a terminating 0, count how many primes lie strictly above n and at most 2n.	Medium4	Number theoryMath+1	No attempts yet	1s	256 MB	Judgeable
Pablo Squarson's HeadacheGiven how N unit squares are attached one by one to an existing square in one of four directions, compute the width and height of the resulting figure.	Medium4	SimulationArray+2	No attempts yet	1s	128 MB	Judgeable
Amazing MazesGiven a rectangular grid with walls between cells, find the number of cells on the shortest path from the top-left opening to the bottom-right opening, or 0 if none exists.	Medium4	BFSGraph+2	No attempts yet	1s	128 MB	Judgeable
Next MayorSimulate the pebble-passing game and output the index of the candidate who ends up holding every pebble.	Medium4	SimulationImplementation	No attempts yet	1s	128 MB	Judgeable
Ohga's FortuneFor each dataset, simulate each of up to 100 operations over up to 10 years to find the largest final fund.	Medium4	SimulationImplementation+1	No attempts yet	1s	128 MB	Judgeable
ElevatorAn elevator with buttons that move up U or down D floors, staying within floors 1 to F, needs the minimum presses to go from floor S to floor G.	Medium4	BFSGraph+2	No attempts yet	1s	256 MB	Judgeable
Money MattersGiven each person's balance and a friendship graph, decide whether all debts can be settled by moving money only within connected components.	Medium4	Union-findGraph+1	No attempts yet	1s	128 MB	Judgeable
Phone ListGiven a list of distinct phone numbers, decide whether any number is a prefix of another.	Medium4	TrieString+1	No attempts yet	1s	256 MB	Judgeable
Web PagesFor each line of HTML-looking text, decide whether every opening tag has a matching closing tag and all tags nest properly.	Medium4	StackString+2	No attempts yet	1s	128 MB	Judgeable
MapsFor each scenario, count how many positions in the map contain an exact, non-rotated copy of the rig pattern, with both X and dot cells matching. The image is trimmed, so every position in its bounding box matters.	Medium4	Brute forceImplementation+2	No attempts yet	1s	128 MB	Judgeable
DiscountsFor each product, given buy-B-get-F-free offers and query amounts, find the maximum saving in dollars for each quantity.	Medium4	Dynamic programmingGreedy+2	No attempts yet	1s	128 MB	Judgeable
Matrix PowersGiven a square matrix, a modulus, and an exponent, compute the matrix raised to that power with all entries kept modulo M.	Medium4	MatrixDivide and conquer+1	No attempts yet	1s	128 MB	Judgeable
ArmageddonCompute the time left before firing a missile can no longer deflect two asteroid pieces to miss Earth, given current distance, separation angle, and both speeds.	Medium4	MathImplementation+2	No attempts yet	1s	128 MB	Judgeable
Preventing ParadoxesGiven the vertices of a simple polygon in order, decide whether the traversal orientation is clockwise or counterclockwise.	Medium4	GeometryImplementation	No attempts yet	1s	128 MB	Judgeable
Geologic StrataGiven a grid of sediment strata and fossils, assign each fossil the lowest adjacent stratum and check whether every fossil's period matches the target time.	Medium4	ImplementationMatrix+2	No attempts yet	1s	128 MB	Judgeable