Problems

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Total results29,478 problems

Alien Socks
Easy3
Math, Greedy+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Attendance Check
Easy3
Implementation, Simulation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Shampoo
Easy3
Implementation, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Fishing
Easy3
Sliding window, Array+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Pyramids
Easy3
Greedy, Math+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Sled
Easy3
Simulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Animals
Easy3
Intervals, Implementation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Couriers
Easy3
Simulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Encryption
Easy3
Implementation, Math+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Sorting
Easy3
Sorting, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Equations
Easy3
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Elevator
Easy3
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Laundry
Easy3
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Bus
Easy3
Implementation, Simulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Ancient Keyboard
Easy3
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Scrabble Scoring
Easy3
Implementation, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
A DP Problem
Easy3
String, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Skew Binary
Easy3
Math, Greedy+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Number Steps
Easy3
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Polynomial Remainder Operation
Easy3
Math, Bit manipulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Web Navigation
Easy3
Stack, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Undercut
Easy3
Implementation, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Currency Exchange
Easy3
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Ride My Bicycle
Easy3
Sorting, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sequence
Easy3
Math, Brute force
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Untidy Desktops
Easy3
Geometry, Brute force
No attempts yet
Time limit
7s
Memory limit
128 MB
Judgeable
Box
Easy3
Implementation, Sorting+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Easy Trading
Easy3
Array, Prefix sum+2
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Factoring a Polynomial
Easy3
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Social Networking Application
Easy3
Union-find, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Prehistoric Operating Systems
Easy3
Dynamic programming, Combinatorics+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Kick-Tipp
Easy3
Implementation, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Stamps
Easy3
Greedy, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Incomplete chess boards
Easy3
Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Strategies
Easy3
Simulation, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Yeehaa!
Easy3
Geometry, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Ancient Plates
Easy3
Implementation, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cramer's Rule
Easy3
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Automatic Poetry
Easy3
String, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Body Size Ranking
Easy3
Array, Brute force
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
On the Bus
Easy3
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Noughts & Crosses
Easy3
Simulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Brackets
Easy3
Stack, String
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Anagrams
Easy3
Hash map, String+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tennis
Easy3
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Outfits
Easy3
Array, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Matryoshka Dolls
Easy3
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Scrabble
Easy3
Array, String+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Election
Easy3
Simulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Nash Equilibrium
Easy3
Brute force, Matrix+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Pseudographical Recognizer
Easy3
Implementation, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Kingdom Subdivision
Easy3
Geometry, Math+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
In Queries
Easy3
Array, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Chosen Sub Matrix
Easy3
Brute force, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Email from the Professor
Easy3
Implementation, Array+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sudoku Checker
Easy3
Hash map, Implementation+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
ACM Rank Table
Easy3
Sorting, Implementation+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Circle Drawing
Easy3
Simulation, Geometry+1
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Simple Prefix Compression
Easy3
String, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Very Simple Problem
Easy3
Implementation, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Big Number
Easy3
Math, Number theory+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Supermarket
Easy3
Sorting, Array+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sequences without Stammers
Easy3
String, Combinatorics+1
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Intervals
Easy3
Sorting, Intervals+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Subdivision of Kingdom
Easy3
Brute force, Bit manipulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Intelligence Test
Easy3
Array, Two pointers+1
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Table and Chairs
Easy3
Math, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Rectilinear Polygon With Area Equal to Its Vertex Count
Easy3
Implementation, Geometry+2
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Rectangles
Easy3
Math, Brute force+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tables
Easy3
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Computation of a Road Network Plan
Easy3
Tree, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Can You Exponentiate?
Easy3
Math, Number theory+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Jasio
Easy3
String, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Dance
Easy3
Graph, DFS
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Chaos and the Stonki
Easy3
String, Hash map+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sticks
Easy3
Hash map, Array+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Binary Scale
Easy3
Sorting
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Network Investment
Easy3
DFS, Tree
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Program
Easy3
Stack
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
The Hare
Easy3
BFS, Graph+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Necklaces
Easy3
Simulation, String
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Statistics
Easy3
String, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Postcard
Easy3
Combinatorics, Array
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
The Tape
Easy3
Greedy, Array
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
List
Easy3
Math, Array
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Smallest Missing Multiple
Easy3
Hash map, Math
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Sorting the Jewelry
Easy3
Sorting
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Shop
Easy3
Hash map
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Smallest Perfect-Square Multiple
Easy3
Number theory
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Lottery
Easy3
Greedy, String
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Passing Cars
Easy3
Prefix sum, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Grasshopper
Easy3
Greedy, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Bet
Easy3
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Nails
Easy3
Sorting, Greedy
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Grasshopper 2
Easy3
Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Forest
Easy3
Hash map
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Dividers
Easy3
Array, Greedy
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Taps
Easy3
Greedy, Sorting
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Two Towers
Easy3
Greedy, Two pointers+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Divisor Set Inclusion
Easy3
Number theory
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Alien SocksGiven counts of socks in s colors, find the smallest number of socks to draw to guarantee k socks of one color, or -1 if impossible.	Easy3	MathGreedy+1	No attempts yet	1s	1024 MB	Judgeable
Attendance CheckGiven a permutation forming one cycle, find the student who responds last when the calling chain starts at student k.	Easy3	ImplementationSimulation+2	No attempts yet	1s	1024 MB	Judgeable
ShampooGiven N days and a sorted list of holidays, count how many days residents wash their hair under the stated daily rules.	Easy3	ImplementationSimulation	No attempts yet	1s	1024 MB	Judgeable
FishingFind the starting day among the first N days whose window of k consecutive days contains the most rainy days, choosing the smallest index on a tie.	Easy3	Sliding windowArray+1	No attempts yet	1s	1024 MB	Judgeable
PyramidsGiven N blocks, repeatedly take out the largest triangular number that fits, and print the resulting pyramid heights in decreasing order.	Easy3	GreedyMath+2	No attempts yet	1s	1024 MB	Judgeable
SledSimulate a sled whose speed changes by a_i on each segment and drops by 1 at junctions whenever it exceeds S; report the final speed.	Easy3	SimulationImplementation+1	No attempts yet	1s	1024 MB	Judgeable
AnimalsGiven N active time intervals, find whether they share a common moment and, if so, the longest interval when all animals are active.	Easy3	IntervalsImplementation+2	No attempts yet	1s	1024 MB	Judgeable
CouriersSimulate two couriers who each take an incoming order if free, preferring the faster one, and total each courier's earnings.	Easy3	SimulationImplementation+1	No attempts yet	1s	1024 MB	Judgeable
EncryptionGiven a string encrypted with the rule x -> x^3 mod 29 + 1, recover and print the original symbols.	Easy3	ImplementationMath+2	No attempts yet	1s	1024 MB	Judgeable
SortingA full comparison table between two hidden permutations of 1..N is given; recover the value on every card.	Easy3	SortingImplementation	No attempts yet	1s	1024 MB	Judgeable
EquationsGiven sums of each number paired with the last number, plus the total sum, recover all N original numbers.	Easy3	MathImplementation+1	No attempts yet	1s	1024 MB	Judgeable
ElevatorRusnė goes from floor 0 to floor N using the elevator for at most K segments; minimize the total height of the segments she climbs on foot.	Easy3	GreedySorting+1	No attempts yet	1s	1024 MB	Judgeable
LaundryGiven colors partitioned into washable groups and counts of clothes per color, find how many machine loads of capacity M are needed.	Easy3	MathImplementation+2	No attempts yet	1s	1024 MB	Judgeable
BusTrack how many passengers are on the bus after each stop and report the largest number of them that exceeds the seat count K.	Easy3	ImplementationSimulation+1	No attempts yet	1s	1024 MB	Judgeable
Ancient KeyboardSimulate a keyboard where each of up to 26 keys toggles an LED at two given times, and output the letter matching the LED count at each time step until all intervals end.	Easy3	SimulationImplementation+2	No attempts yet	1s	128 MB	Judgeable
Scrabble ScoringScore each Scrabble play by parsing its start square and direction, applying letter and word bonus multipliers from the fixed 15x15 board.	Easy3	ImplementationSimulation+2	No attempts yet	1s	128 MB	Judgeable
A DP ProblemParse each linear equation without parentheses, solve for x, and report the floored solution or whether it is impossible or an identity.	Easy3	StringImplementation+1	No attempts yet	1s	128 MB	Judgeable
Skew BinaryConvert each decimal number into its unique skew binary representation, printed as the sorted ranks of its nonzero digits.	Easy3	MathGreedy+2	No attempts yet	1s	128 MB	Judgeable
Number StepsGiven a point, print the number written there by a fixed boustrophedon path over the plane, or No Number if the point is empty.	Easy3	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Polynomial Remainder OperationMultiply two binary polynomials over GF(2) and print the remainder modulo a third polynomial, all given as bit strings.	Easy3	MathBit manipulation+1	No attempts yet	1s	128 MB	Judgeable
Web NavigationSimulate browser back and forward navigation using two stacks, printing the current URL after each command.	Easy3	StackSimulation+1	No attempts yet	1s	128 MB	Judgeable
UndercutScore a five-round card game where players reveal numbered cards each round, applying undercut and tie rules, and print both totals.	Easy3	ImplementationSimulation+2	No attempts yet	1s	128 MB	Judgeable
Currency ExchangeGiven a 5x5 exchange-rate table where every conversion rounds to the nearest hundredth, simulate each trip and report the final dollar amount rounded to cents.	Easy3	SimulationImplementation+2	No attempts yet	1s	128 MB	Judgeable
Ride My BicycleCompute the ratio of each of the 21 front and back gear pairs, round to two decimals, and print them sorted by ratio then chain ring.	Easy3	SortingImplementation+1	No attempts yet	1s	128 MB	Judgeable
SequenceGiven up to five strictly increasing numbers, find the smallest base at most 10 in which their values, read as base-b numerals, form an arithmetic sequence.	Easy3	MathBrute force	No attempts yet	1s	128 MB	Judgeable
Untidy DesktopsGiven n axis-aligned rectangles, count how many overlap at least one other rectangle, boundaries included.	Easy3	GeometryBrute force	No attempts yet	7s	128 MB	Judgeable
BoxGiven six rectangles that can be rotated, decide whether they form the three pairs of opposite faces of a rectangular box.	Easy3	ImplementationSorting+1	No attempts yet	2s	128 MB	Judgeable
Easy TradingGiven daily prices, compute moving averages over the last m and n days and print a buy or sell signal whenever the trend between them reverses.	Easy3	ArrayPrefix sum+2	No attempts yet	2s	128 MB	Judgeable
Factoring a PolynomialGiven a polynomial with integer coefficients of degree at most 20, decide whether it is irreducible over the reals.	Easy3	MathImplementation+1	No attempts yet	1s	512 MB	Judgeable
Social Networking ApplicationGiven a friendship graph, answer queries asking whether two users lie in the same connected component.	Easy3	Union-findGraph+2	No attempts yet	1s	128 MB	Judgeable
Prehistoric Operating SystemsCount binary strings of length n with no two adjacent D's, where D means DOORS and O means any other brand, for up to 40 test values of n.	Easy3	Dynamic programmingCombinatorics+2	No attempts yet	1s	128 MB	Judgeable
Kick-TippGiven each participant's predicted scores and the actual results over several rounds, compute total points, award round dots to top scorers, and print the sorted standings.	Easy3	ImplementationSorting+1	No attempts yet	1s	128 MB	Judgeable
StampsGiven a needed stamp count and each friend's offer, find the fewest friends whose offers sum to at least the needed amount, or report impossible.	Easy3	GreedySorting+2	No attempts yet	1s	128 MB	Judgeable
Incomplete chess boardsFor each pair of removed squares on an 8x8 board, decide whether the remaining 62 squares can be tiled by 31 dominoes.	Easy3	Math	No attempts yet	1s	128 MB	Judgeable
StrategiesGiven contest time and problem times, simulate three orderings (input, ascending, descending) and pick the winner by problems solved, then score, then Steve.	Easy3	SimulationSorting+1	No attempts yet	1s	128 MB	Judgeable
Yeehaa!Given the large circle radius R and the count n of equal small circles packed around the inside rim, compute the small circle radius r.	Easy3	GeometryMath+1	No attempts yet	1s	128 MB	Judgeable
Ancient PlatesApply given PERM and SHIFT rules to lines, words, or characters of a block of text, then print the result.	Easy3	ImplementationSimulation+1	No attempts yet	1s	128 MB	Judgeable
Cramer's RuleGiven several 3x3 linear systems, compute four determinants by Cramer's rule and either print the unique solution rounded to three decimals or report none.	Easy3	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Automatic PoetryGiven a bracketed first line and a truncated second line ending in dots, rebuild the second line by splicing the bracket contents in the order s4s3s2s5.	Easy3	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Body Size RankingFor each person, count how many others are both heavier and taller, and print that count plus one.	Easy3	ArrayBrute force	No attempts yet	1s	128 MB	Judgeable
On the BusTrack passengers boarding and alighting over a series of stops, never exceeding the bus capacity, and report the final count.	Easy3	SimulationImplementation	No attempts yet	1s	128 MB	Judgeable
Noughts & CrossesReplay each game from its recorded moves and report the winner (X or O) or Draw, ignoring moves after the win.	Easy3	SimulationImplementation+1	No attempts yet	1s	128 MB	Judgeable
BracketsFor each line of code until the '#' line, decide whether its round, square, and curly brackets are matched and correctly nested.	Easy3	StackString	No attempts yet	1s	128 MB	Judgeable
AnagramsGiven several word lists, print the first word in each list that has the most anagrams, along with that count.	Easy3	Hash mapString+1	No attempts yet	1s	128 MB	Judgeable
TennisRead a sequence of tennis points (A/B), split it into completed games using the 15-30-40-deuce rules, and output the final game count.	Easy3	SimulationImplementation	No attempts yet	1s	128 MB	Judgeable
OutfitsGiven two wardrobes numbered from opposite ends with at most one removal each, report for each day whether both girls picked the same physical outfit.	Easy3	ArrayImplementation+1	No attempts yet	1s	128 MB	Judgeable
Matryoshka DollsGiven doll heights, nest each doll inside a strictly taller doll, each holding at most one, to minimize the number of outermost dolls.	Easy3	GreedySorting+1	No attempts yet	1s	128 MB	Judgeable
ScrabbleGiven up to 1000 short dictionary words and a set of letter and blank tiles, count how many words the tiles can spell.	Easy3	ArrayString+2	No attempts yet	1s	128 MB	Judgeable
ElectionSimulate instant-runoff voting over at most 5 candidates and 20 preference groups, eliminating the lowest scorer each round.	Easy3	SimulationImplementation+1	No attempts yet	1s	128 MB	Judgeable
Nash EquilibriumGiven two m by n payoff matrices for players A and B, list every action pair where each player's action is a best response to the other's.	Easy3	Brute forceMatrix+1	No attempts yet	1s	128 MB	Judgeable
Pseudographical RecognizerGiven a small grid of line and dot characters, decide whether the drawn characters form exactly one connected straight segment.	Easy3	ImplementationSimulation+1	No attempts yet	1s	128 MB	Judgeable
Kingdom SubdivisionGiven a simple polygon's integer vertices, output half its area as a reduced fraction p/q.	Easy3	GeometryMath+1	No attempts yet	2s	256 MB	Judgeable
In QueriesMaintain a 5-column table with seeded initial rows and process insert, remove, max, min, and range-count queries over the columns.	Easy3	ArrayImplementation+2	No attempts yet	1s	128 MB	Judgeable
The Chosen Sub MatrixFor each N x N matrix, find the M x M sub matrix with the fewest distinct values, breaking ties by larger descending value lists, then by smaller top-left row and column.	Easy3	Brute forceImplementation+2	No attempts yet	1s	128 MB	Judgeable
Email from the ProfessorWrite each message row by row into a grid of width k, then read columns in the order given by a permutation key, dropping padding cells.	Easy3	ImplementationArray+2	No attempts yet	1s	128 MB	Judgeable
Sudoku CheckerGiven an N^2 by N^2 grid with zeros for blanks, decide whether every row, column, and N by N square holds distinct nonzero numbers.	Easy3	Hash mapImplementation+1	No attempts yet	2s	128 MB	Judgeable
ACM Rank TableAggregate each team's runs under ACM penalty rules, then sort teams by solved count, total time, and team number.	Easy3	SortingImplementation+1	No attempts yet	2s	128 MB	Judgeable
Circle DrawingPaint circles onto a grid, later circles overwriting earlier ones, then print the final color of every pixel.	Easy3	SimulationGeometry+1	No attempts yet	3s	128 MB	Judgeable
Simple Prefix CompressionSum stored lengths after prefix compression: each string stores a control byte plus the part not shared as a prefix with the previous string.	Easy3	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Very Simple ProblemFind problems that more than half of the jury rated with its minimum score and that no jury member rated with its maximum score.	Easy3	ImplementationArray	No attempts yet	1s	128 MB	Judgeable
Big NumberFor each m up to 10^7, print the number of decimal digits in m factorial.	Easy3	MathNumber theory+1	No attempts yet	2s	128 MB	Judgeable
SupermarketFind the k-th smallest value among n amounts spent, with values bounded by 100000.	Easy3	SortingArray+2	No attempts yet	1s	128 MB	Judgeable
Sequences without StammersPrint the smallest alphabet size for which a square-free (stammer-free) string of length n exists.	Easy3	StringCombinatorics+1	No attempts yet	3s	128 MB	Judgeable
IntervalsGiven n closed intervals, merge all overlapping or touching ones and print the resulting disjoint intervals in ascending order.	Easy3	SortingIntervals+2	No attempts yet	1s	128 MB	Judgeable
Subdivision of KingdomSplit n towns (n even, n <= 26) into two halves of equal size so that the number of roads crossing between the halves is minimized.	Easy3	Brute forceBit manipulation+1	No attempts yet	1s	128 MB	Judgeable
Intelligence TestGiven a fixed sequence and several queries, decide for each query sequence whether it is a subsequence of the fixed sequence.	Easy3	ArrayTwo pointers+1	No attempts yet	3s	512 MB	Judgeable
Table and ChairsGiven a rectangular tabletop A by B and square chairs of side K, find the maximum number of non-overlapping chairs whose backrest lies along a table edge.	Easy3	MathGreedy+1	No attempts yet	1s	128 MB	Judgeable
Rectilinear Polygon With Area Equal to Its Vertex CountGiven n, print a canonical rectilinear polygon outline with n vertices and area n, or NIE when n is odd or below 4.	Easy3	ImplementationGeometry+2	No attempts yet	5s	128 MB	Judgeable
RectanglesCount axis-aligned rectangles on an n by m grid of points whose perimeter is at least p.	Easy3	MathBrute force+1	No attempts yet	1s	128 MB	Judgeable
TablesGiven box screw counts, find the fewest boxes whose screws total at least s*k.	Easy3	GreedySorting	No attempts yet	1s	128 MB	Judgeable
Computation of a Road Network PlanGiven the number of cities n and a target diameter d, print a specific tree: a path of length d with all remaining cities hung off its middle vertex.	Easy3	TreeImplementation+1	No attempts yet	1s	128 MB	Judgeable
Can You Exponentiate?Given a and b up to 1e9, print the last decimal digit of a^b.	Easy3	MathNumber theory+1	No attempts yet	1s	128 MB	Judgeable
JasioCount words that contain a palindrome substring of length at least 2, both literally and with i=j and p=b=d treated as equal.	Easy3	StringImplementation+1	No attempts yet	1s	128 MB	Judgeable
The DanceFind the largest number of boy-girl pairs that can dance at once when each boy may only invite a girl he knows.	Easy3	GraphDFS	No attempts yet	1s	128 MB	Judgeable
Chaos and the StonkiEach entry is a name with hyphens inserted anywhere and letters possibly lowercased; count how many distinct real names (uppercase only) appear.	Easy3	StringHash map+1	No attempts yet	1s	128 MB	Judgeable
SticksGiven stick lengths, repeatedly merge pairs of equal length into doubled sticks and report how many distinct sticks remain.	Easy3	Hash mapArray+1	No attempts yet	1s	128 MB	Judgeable
Binary ScaleSort the given (reading, precision) pairs by reading divided by 2 to the precision, breaking ties by smaller reading.	Easy3	Sorting	No attempts yet	1s	128 MB	Judgeable
Network InvestmentFind the tree edge whose removal maximizes the product of the two component sizes.	Easy3	DFSTree	No attempts yet	1s	128 MB	Judgeable
ProgramCheck whether the bracket string is correct and print its maximum nesting depth, or NIE when it is not.	Easy3	Stack	No attempts yet	1s	512 MB	Judgeable
The HareFind the fewest knight jumps from the start cell to the burrow on a grid with blocked cells, or output NIE when unreachable.	Easy3	BFSGraph+1	No attempts yet	1s	512 MB	Judgeable
NecklacesSplit each circular necklace string into runs of equal size and shade and report the longest and shortest run, preferring larger then lighter beads on ties.	Easy3	SimulationString	No attempts yet	1s	512 MB	Judgeable
StatisticsCount how many times each requested item appears in the article: spaces, digit runs, letter runs, period-ended sentences with a word, and palindromic words.	Easy3	StringImplementation	No attempts yet	1s	512 MB	Judgeable
PostcardCount the contiguous segments that keep at least one mountain of height m or more after trimming both ends.	Easy3	CombinatoricsArray	No attempts yet	1s	512 MB	Judgeable
The TapeFind the largest distance between two positions holding different values in each test case, printing BRAK if all values are equal.	Easy3	GreedyArray	No attempts yet	1s	512 MB	Judgeable
ListAfter moving the last k numbers of 1 to n to the front, sum the entries from position i to position j.	Easy3	MathArray	No attempts yet	1s	512 MB	Judgeable
Smallest Missing MultipleFind the smallest positive multiple of k that is absent from the given set of n distinct integers.	Easy3	Hash mapMath	No attempts yet	1s	512 MB	Judgeable
Sorting the JewelrySort up to 150 lowercase strings by increasing length, breaking ties in lexicographic order.	Easy3	Sorting	No attempts yet	1s	512 MB	Judgeable
ShopAdd up the quantities for each product number and print the totals in first-appearance order.	Easy3	Hash map	No attempts yet	2s	512 MB	Judgeable
Smallest Perfect-Square MultipleRead n and print the smallest multiple of n that is a perfect square.	Easy3	Number theory	No attempts yet	1s	128 MB	Judgeable
LotteryChange as few letters of the given A, B, or C string as possible so no two neighbors match.	Easy3	GreedyString	No attempts yet	1s	128 MB	Judgeable
Passing CarsCount pairs of cars moving toward each other where an eastbound car stands west of a westbound car.	Easy3	Prefix sumArray	No attempts yet	1s	128 MB	Judgeable
GrasshopperThe grasshopper crosses width x with the fewest jumps, starting at length s and halving each later jump rounded down, with 1 always allowed.	Easy3	GreedySimulation+1	No attempts yet	1s	128 MB	Judgeable
The BetTurn the fewest dice so exactly k of the six faces appear, keeping the most frequent faces and adding missing ones.	Easy3	GreedySorting+1	No attempts yet	1s	128 MB	Judgeable
NailsLower at most k nails to match a chosen height and maximize how many nails share that height.	Easy3	SortingGreedy	No attempts yet	1s	128 MB	Judgeable
Grasshopper 2Decide whether jumps of lengths s, s/2, s/4, and so on can reach or pass distance x in finitely many jumps.	Easy3	Math	No attempts yet	1s	128 MB	Judgeable
ForestCount distinct species, since the thickest tree of each species could be the oldest.	Easy3	Hash map	No attempts yet	1s	128 MB	Judgeable
DividersCount the positions where the first k entries hold exactly 1 to k by tracking the running maximum.	Easy3	ArrayGreedy	No attempts yet	1s	128 MB	Judgeable
TapsClose the fewest flowing taps so the average temperature of the water still flowing reaches at least w.	Easy3	GreedySorting	No attempts yet	1s	128 MB	Judgeable
Two TowersRemove the fewest blocks from the tops of two towers so the remaining towers have equal height.	Easy3	GreedyTwo pointers+1	No attempts yet	1s	128 MB	Judgeable
Divisor Set InclusionDecide for each pair whether every divisor of a also divides b, which holds exactly when a divides b.	Easy3	Number theory	No attempts yet	1s	128 MB	Judgeable