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Total results2,362 problems

Quake Live (Small2)
Easy2
Brute force, Combinatorics
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Card Shuffle (Small)
Easy2
Simulation, Array
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Program within a Program (Small)
Easy2
Implementation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Investing at the Market
Easy2
Brute force, Array
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Investing at the Market (Large)
Easy2
Brute force
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Odd Man Out
Easy2
Bit manipulation, Array+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Reverse Word Order
Easy2
String, Implementation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Reverse Words (Large)
Easy2
String, Implementation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
T9 Spelling (Small)
Easy2
String, Implementation+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Immigrate to the CTP principality
Easy2
Implementation, String+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tojaengi's Walk to School
Easy2
Combinatorics, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Mini Fantasy War
Easy2
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Starman
Easy2
Array, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bitwise Operations on Binary Numbers
Easy2
String, Bit manipulation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
XORXORXOR
Easy2
Bit manipulation, Math
No attempts yet
Time limit
0.2s
Memory limit
512 MB
Judgeable
Changyong's Clock
Easy2
Simulation, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Lobby
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Cameras
Easy2
String, Implementation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Three Sums
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Formula
Easy2
Geometry, Math+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Adding god to nicknames
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Router 4
Easy2
Implementation, Simulation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Manhattan Taxi
Easy2
Implementation, Brute force+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Matches
Easy2
Geometry, Math+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Chop Cup
Easy2
Simulation, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Divisor Count
Easy2
Number theory, Brute force
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Tic Tac Toe
Easy2
Implementation, Matrix+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
The real Manhattan distance
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Palindrome
Easy2
String, Two pointers+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Collatz Sequence
Easy2
Simulation, Implementation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Chessboard
Easy2
Array, Implementation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Least Common Multiple
Easy2
Math, Number theory+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
A New Alphabet
Easy2
String, Hash map+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Quick Estimates
Easy2
String, Math+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Room Assignment
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Jumbled Compass
Easy2
Math, Implementation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Math Contest
Easy2
Number theory, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Stock Investment
Easy2
Array, Greedy
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Four Arithmetic Operations
Easy2
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Graph Maximum Matching
Easy2
Graph, Backtracking+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
László Babai
Easy2
Graph, Brute force+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Anniversary Cake
Easy2
Geometry, Implementation+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Boys and Girls
Easy2
Implementation, Brute force+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Data Plan
Easy2
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
Cleaning Stations
Easy2
Implementation, Array+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Walking in time
Easy2
Brute force, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
The Funniest Digital Laughter
Easy2
String, Two pointers
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Dangerous Dive
Easy2
Array, Hash map
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Lost Boots
Easy2
Hash map, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Optical mark reading
Easy2
Implementation, Brute force
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Alarm Clock
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Sub-prime
Easy2
Array, Implementation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Dividing Nlogônia
Easy2
Implementation, Math
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Pokemon GO
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
32 MB
Judgeable
Second Cheapest Present
Easy2
Sorting, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Holes
Easy2
String, Implementation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Olympic Games
Easy2
Implementation, Math
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Virus
Easy2
String, Simulation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Alpha Puzzle
Easy2
Simulation, String+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Splitting into Two Teams
Easy2
Brute force, Math+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Farm robot scarecrow
Easy2
Simulation, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Unit Conversion
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Magic Squares
Easy2
Implementation, Matrix
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Fuel
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Luhn Algorithm
Easy2
String, Implementation+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Telephone
Easy2
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Enlarging the Cow Signal
Easy2
Implementation, Array
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Income tax
Easy2
Implementation, Math
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Key Maker
Easy2
Array, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Grades
Easy2
Array, Math+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Bridge Honor Points
Easy2
Implementation, String+1
No attempts yet
Time limit
1s
Memory limit
32 MB
Judgeable
Sitting (Small)
Easy2
Brute force, Implementation
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Country Leader (Small)
Easy2
String, Implementation+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Country Leader
Easy2
String, Sorting+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Counting Sheep (Large)
Easy2
Math, Simulation+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
String Set
Easy2
Hash map
No attempts yet
Time limit
2s
Memory limit
1536 MB
Judgeable
Microwave
Easy2
Math, Implementation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Refreshment Area
Easy2
Array, Implementation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
One Hundred to Ten
Easy2
Math, Number theory+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Base 9
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Fibonacci-like Sequence
Easy2
Dynamic programming, Math+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Bovine Genomics (Bronze)
Easy2
Implementation, Brute force+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Birthday Graph
Easy2
Array, String+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Grid Pattern
Easy2
Implementation, Simulation+1
No attempts yet
Time limit
10s
Memory limit
512 MB
Judgeable
Speed Limit
Easy2
Implementation, Math+1
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Outer Triangle Sum
Easy2
Implementation, Array+2
No attempts yet
Time limit
10s
Memory limit
512 MB
Judgeable
Linear Equation
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
X X glued
Easy2
String, Implementation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Card Game Contest
Easy2
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Perfect, deficient, or abundant
Easy2
Math, Brute force+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
2017 Yonsei University Programming Contest
Easy2
Brute force, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Hongjun surrounded by fans
Easy2
Implementation, String
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
We Lost Again Today
Easy2
Implementation, Simulation+1
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
2017 Ajou University Programming Contest (Small)
Easy2
Sorting, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
2017 Ajou Programming Contest (Large)
Easy2
Sorting
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Empathy
Easy2
Math, String+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Jeonbuk National University
Easy2
Implementation, Simulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Recovering a Damaged ISBN Digit
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
I am happy~
Easy2
Math, Implementation+2
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Fox Sign
Easy2
Implementation, Array
No attempts yet
Time limit
0.5s
Memory limit
512 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Quake Live (Small2)Split the given players into two equal teams so the two skill totals differ as little as possible.	Easy2	Brute forceCombinatorics	No attempts yet	5s	512 MB	Judgeable
Card Shuffle (Small)Simulate C segment-to-top cuts on a deck of M ordered cards and report the card at position W.	Easy2	SimulationArray	No attempts yet	5s	512 MB	Judgeable
Program within a Program (Small)Given N, output the fixed 27-line robot program with nine lines filled in from the binary digits of N.	Easy2	Implementation	No attempts yet	5s	512 MB	Judgeable
Investing at the MarketChoose a buy month and a later sell month from 12 prices to maximize whole-unit profit, breaking ties by lower buy price.	Easy2	Brute forceArray	No attempts yet	5s	512 MB	Judgeable
Investing at the Market (Large)Choose one buy month and a later sell month from 12 monthly prices to maximize profit from whole shares bought with fixed money.	Easy2	Brute force	No attempts yet	5s	512 MB	Judgeable
Odd Man OutGiven an odd-length list of invitation codes where every value appears twice except one, find the value that appears once.	Easy2	Bit manipulationArray+1	No attempts yet	5s	512 MB	Judgeable
Reverse Word OrderGiven N lines of space-separated words, print each line's words in reverse order prefixed with the case number.	Easy2	StringImplementation	No attempts yet	5s	512 MB	Judgeable
Reverse Words (Large)Read each line of words and print the words in reverse order, prefixed by the case number.	Easy2	StringImplementation	No attempts yet	5s	512 MB	Judgeable
T9 Spelling (Small)Map each letter of a short message to its keypad digit and repeat count, inserting a space between consecutive letters that share the same key.	Easy2	StringImplementation+2	No attempts yet	5s	512 MB	Judgeable
Immigrate to the CTP principalityConvert each item between uppercase letters and their alphabet positions (A=1 to Z=26), in the direction given by the mode character.	Easy2	ImplementationString+2	No attempts yet	1s	128 MB	Judgeable
Tojaengi's Walk to SchoolCount monotone lattice paths from (1,1) to (w,h) that pass through a given shop, modulo 1000007.	Easy2	CombinatoricsMath	No attempts yet	1s	128 MB	Judgeable
Mini Fantasy WarFor each character, add gear changes to the four base stats, clamp HP and MP to at least 1 and attack to at least 0, then print the weighted combat power.	Easy2	ImplementationMath	No attempts yet	1s	128 MB	Judgeable
StarmanGiven up to 100 year ranges, print the Bowie albums released within each range, in release order, with a count first.	Easy2	ArrayImplementation	No attempts yet	1s	128 MB	Judgeable
Bitwise Operations on Binary NumbersGiven two equal-length binary strings, output their bitwise AND, OR, XOR, and the complemented forms of each, keeping length and leading zeros.	Easy2	StringBit manipulation+1	No attempts yet	2s	512 MB	Judgeable
XORXORXORXOR the value B into A exactly C times and print the result.	Easy2	Bit manipulationMath	No attempts yet	0.2s	512 MB	Judgeable
Changyong's ClockTrack a clock's time on a 24-hour dial, turning it forward or backward by c seconds and answering queries for the current time.	Easy2	SimulationMath+1	No attempts yet	1s	512 MB	Judgeable
LobbyGiven the seat counts of two parties, find how many independents must vote yes for a strict majority.	Easy2	MathImplementation	No attempts yet	2s	512 MB	Judgeable
CamerasRead n eight-character plates and print each one that matches a fixed pattern of digits and a capital letter, in input order.	Easy2	StringImplementation+1	No attempts yet	2s	512 MB	Judgeable
Three SumsFor each N, print the sum of the first N positive integers, the first N odd numbers, and the first N even numbers.	Easy2	MathImplementation	No attempts yet	2s	512 MB	Judgeable
FormulaGiven triangle vertex coordinates and a measured incircle radius, compute the radius from the formula and print the percentage difference.	Easy2	GeometryMath+1	No attempts yet	2s	512 MB	Judgeable
Adding god to nicknamesGiven N nicknames split into syllables by spaces, replace the first syllable with god and print the result.	Easy2	StringImplementation	No attempts yet	1s	512 MB	Judgeable
Router 4Print the fixed two-layer router built from N inputs, r merge nodes, r split nodes, and N outputs, with M = 2N + r^2 connections.	Easy2	ImplementationSimulation	No attempts yet	2s	512 MB	Judgeable
Manhattan TaxiGiven your waiting intersection and up to 100 taxi positions on a 100x100 grid, print the coordinates of the taxi with the smallest Manhattan distance.	Easy2	ImplementationBrute force+2	No attempts yet	2s	512 MB	Judgeable
MatchesFor each match length, decide whether it fits in a W by H box, meaning its length is at most the diagonal sqrt(W^2+H^2).	Easy2	GeometryMath+1	No attempts yet	2s	512 MB	Judgeable
Chop CupTrack which of three cups hides the ball after a sequence of swaps given as letters A, B, and C.	Easy2	SimulationImplementation	No attempts yet	2s	512 MB	Judgeable
Divisor CountFor each of up to 10 values of n below 10000, print n and its divisor count.	Easy2	Number theoryBrute force	No attempts yet	2s	512 MB	Judgeable
Tic Tac ToeRead a 3x3 board of X, O, and dots and print YES if some row, column, or diagonal has three equal non-dot symbols.	Easy2	ImplementationMatrix+1	No attempts yet	2s	512 MB	Judgeable
The real Manhattan distanceGiven two points (x, y, floor), compute the walking distance: down from each floor, plus Manhattan street distance.	Easy2	MathImplementation	No attempts yet	2s	512 MB	Judgeable
PalindromeGiven a lowercase word of at most 20 characters, decide whether it reads the same forwards and backwards.	Easy2	StringTwo pointers+1	No attempts yet	2s	512 MB	Judgeable
Collatz SequenceStarting from n, repeatedly apply the Collatz rule (halve evens, 3n+1 for odds) and print every value from n down to 1 on one line.	Easy2	SimulationImplementation+1	No attempts yet	2s	512 MB	Judgeable
ChessboardPrint an N by M grid of asterisks and dots where the top left cell is an asterisk and adjacent cells always differ.	Easy2	ArrayImplementation+2	No attempts yet	2s	512 MB	Judgeable
Least Common MultipleGiven two integers below 100,000,000, print their least common multiple, which can exceed the 32-bit range.	Easy2	MathNumber theory+1	No attempts yet	2s	512 MB	Judgeable
A New AlphabetReplace each English letter with its fixed symbol string from a 26-entry table, leaving all other characters unchanged.	Easy2	StringHash map+1	No attempts yet	2s	512 MB	Judgeable
Quick EstimatesRead N integers up to 10^100 and print the number of digits in each, counting 0 as one digit.	Easy2	StringMath+1	No attempts yet	2s	512 MB	Judgeable
Room AssignmentCount boys and girls per grade and sum the ceiling of each count divided by the room capacity K.	Easy2	MathImplementation	No attempts yet	2s	512 MB	Judgeable
Jumbled CompassGiven two compass directions from 0 to 359, print the signed rotation with the smallest magnitude that moves the needle from the first direction to the second, breaking ties toward clockwise.	Easy2	MathImplementation+1	No attempts yet	2s	512 MB	Judgeable
Math ContestGiven a huge decimal integer x, print YES if x is divisible by 9 and NO otherwise.	Easy2	Number theoryMath+1	No attempts yet	1s	512 MB	Judgeable
Stock InvestmentGiven each day's profit for three stocks, pick at most one stock per day and maximize the total profit.	Easy2	ArrayGreedy	No attempts yet	1s	128 MB	Judgeable
Four Arithmetic OperationsEach line gives an expression a op b = c with single-digit spacing, and you print correct or wrong answer depending on whether the arithmetic matches the claimed result.	Easy2	MathImplementation+2	No attempts yet	1s	128 MB	Judgeable
Graph Maximum MatchingGiven a small graph, decide whether some edges can be kept so every vertex has degree exactly 1.	Easy2	GraphBacktracking+1	No attempts yet	2s	512 MB	Judgeable
László BabaiFor each of up to 100 test cases, decide whether two simple graphs on 3 vertices given by their edge lists are isomorphic.	Easy2	GraphBrute force+1	No attempts yet	1s	256 MB	Judgeable
Anniversary CakeGiven a rectangle and two interior candles, output the specific cut described by a fixed rule that separates the candles.	Easy2	GeometryImplementation+1	No attempts yet	2s	256 MB	Judgeable
Boys and GirlsArrange n children in a circle with B/G so that exactly x stand next to a boy and exactly y next to a girl, output the lexicographically smallest.	Easy2	ImplementationBrute force+1	No attempts yet	2s	256 MB	Judgeable
Data PlanTrack monthly data allowance that rolls over, subtract each month's usage, and report the megabytes available in month N+1.	Easy2	ImplementationMath	No attempts yet	1s	64 MB	Judgeable
Cleaning StationsGiven weights and a feature matrix, print the indices of the rows whose weighted sum is largest, in ascending order, for each of K data sets.	Easy2	ImplementationArray+1	No attempts yet	2s	512 MB	Judgeable
Walking in timeGiven three credit values, decide whether choosing some of them with signs (+ or -) sums to zero using at least one credit.	Easy2	Brute forceMath+1	No attempts yet	1s	512 MB	Judgeable
The Funniest Digital LaughterGiven a string, ignore the consonants and decide whether the remaining vowels read the same forwards and backwards.	Easy2	StringTwo pointers	No attempts yet	1s	512 MB	Judgeable
Dangerous DiveGiven N volunteers and the R identifiers that returned, list the missing identifiers in ascending order, or print * if all returned.	Easy2	ArrayHash map	No attempts yet	2s	512 MB	Judgeable
Lost BootsCount how many left-right pairs of boots share the same size, reading several test cases until EOF.	Easy2	Hash mapImplementation	No attempts yet	2s	512 MB	Judgeable
Optical mark readingFor each question, read five grey levels; print the single alternative whose value is at most 127, or * if zero or more than one qualify.	Easy2	ImplementationBrute force	No attempts yet	2s	512 MB	Judgeable
Alarm ClockFor each case, compute how many minutes pass from the current time until the alarm time, rolling over to the next day when needed.	Easy2	MathImplementation	No attempts yet	2s	512 MB	Judgeable
Sub-primeGiven each bank's reserve and a list of debentures between banks, check whether every bank ends with a nonnegative balance after all debentures settle at once.	Easy2	ArrayImplementation+1	No attempts yet	2s	512 MB	Judgeable
Dividing NlogôniaGiven a divider point, classify each house coordinate into one of four quadrants or as lying on a dividing line.	Easy2	ImplementationMath	No attempts yet	2s	512 MB	Judgeable
Pokemon GOFor each species, compute how many net 10-candy evolutions are possible, sum them, and find the species with the most evolutions.	Easy2	MathImplementation	No attempts yet	1s	32 MB	Judgeable
Second Cheapest PresentGiven a list of distinct prices, print the second cheapest one, formatted with two decimal places.	Easy2	SortingImplementation	No attempts yet	2s	512 MB	Judgeable
HolesCount the holes in each of N lines of uppercase text, where B counts as two, A D O P Q R count as one, and the rest count as zero.	Easy2	StringImplementation+2	No attempts yet	2s	512 MB	Judgeable
Olympic GamesFor each year, decide whether it is a summer Olympic year, and if so whether the games were held, cancelled by a war, or not yet assigned a city.	Easy2	ImplementationMath	No attempts yet	2s	512 MB	Judgeable
VirusGiven a key and one line of ciphertext, undo a Caesar variant whose shift grows by one per letter and resets after 25.	Easy2	StringSimulation+1	No attempts yet	2s	512 MB	Judgeable
Alpha PuzzleAssign numbers 1 to 26 to letters by scanning the grid and numbering each letter at its first appearance.	Easy2	SimulationString+1	No attempts yet	2s	512 MB	Judgeable
Splitting into Two TeamsGiven four sorted skill levels, split them into two pairs of two and print the smallest possible difference between the two pair sums.	Easy2	Brute forceMath+1	No attempts yet	2s	512 MB	Judgeable
Farm robot scarecrowCount how many times a robot moving clockwise or counter-clockwise around N stations visits a given station, starting at station 1.	Easy2	SimulationImplementation	No attempts yet	2s	512 MB	Judgeable
Unit ConversionGiven x of unit A equals y of unit B, convert each listed amount to the other unit and print the result to six decimals.	Easy2	MathImplementation	No attempts yet	2s	512 MB	Judgeable
Magic SquaresGiven a 4x4 grid, check whether all four row sums and all four column sums are equal, then print whether it is magic.	Easy2	ImplementationMatrix	No attempts yet	2s	512 MB	Judgeable
FuelConvert fuel consumption from miles per gallon to liters per 100 kilometers using the given conversion constants.	Easy2	MathImplementation	No attempts yet	1s	512 MB	Judgeable
Luhn AlgorithmGiven a sixteen-digit card number as a string, check whether it passes the Luhn checksum and print DA or NE.	Easy2	StringImplementation+2	No attempts yet	1s	512 MB	Judgeable
TelephoneFind the base between 2 and 10 whose representation of N has the fewest adjacent digit changes, breaking ties by the largest base.	Easy2	MathImplementation+1	No attempts yet	1s	128 MB	Judgeable
Enlarging the Cow SignalPrint an M by N grid of dots and X characters with each cell repeated K times in both directions.	Easy2	ImplementationArray	No attempts yet	2s	512 MB	Judgeable
Income taxFor each income, subtract 0, 10 percent, or 20 percent tax depending on whether income is at most 1,000,000, at most 5,000,000, or larger.	Easy2	ImplementationMath	No attempts yet	2s	512 MB	Judgeable
Key MakerFor each test case, count how many trash keys have the same cut count and can be deepened, or already match, the customer key.	Easy2	ArrayImplementation	No attempts yet	2s	512 MB	Judgeable
GradesGiven a list of grades, compare the midpoint of the maximum and minimum against the overall average, and report whether they differ by less than 1.	Easy2	ArrayMath+1	No attempts yet	2s	512 MB	Judgeable
Bridge Honor PointsGiven N strings of 13 card characters, add up honor points (A=4, K=3, Q=2, J=1) across all hands and print the total.	Easy2	ImplementationString+1	No attempts yet	1s	32 MB	Judgeable
Sitting (Small)Given a grid of R rows and C columns with R,C at most 5, find the largest set of seats so that no occupied seat has occupied neighbors on both its left and right or both its front and back.	Easy2	Brute forceImplementation	No attempts yet	5s	512 MB	Judgeable
Country Leader (Small)For each test case, find the name with the most distinct letters, breaking ties by ASCII alphabetical order, and print it.	Easy2	StringImplementation+2	No attempts yet	5s	512 MB	Judgeable
Country LeaderFor each test case, pick the name with the most distinct letters, breaking ties by lexicographic order where a space sorts before any letter.	Easy2	StringSorting+2	No attempts yet	5s	512 MB	Judgeable
Counting Sheep (Large)For each N, find the first multiple of N that contains all ten digits, or report that no such multiple exists (only N = 0).	Easy2	MathSimulation+1	No attempts yet	5s	512 MB	Judgeable
String SetCount how many of M query strings appear in a given set S of N strings.	Easy2	Hash map	No attempts yet	2s	1536 MB	Judgeable
MicrowaveGiven a start temperature below target, compute total heating time using per-degree rates for frozen and unfrozen states plus a fixed thawing time.	Easy2	MathImplementation+1	No attempts yet	2s	512 MB	Judgeable
Refreshment AreaCount the number of D-long horizontal or vertical runs of empty cells in an N by M grid.	Easy2	ArrayImplementation+2	No attempts yet	2s	512 MB	Judgeable
One Hundred to TenParse a ratio written as n:m, divide both numbers by their greatest common divisor, and print the reduced ratio in the same format.	Easy2	MathNumber theory+1	No attempts yet	2s	512 MB	Judgeable
Base 9Convert a given decimal integer between 1 and 10000 into its base 9 representation.	Easy2	MathImplementation	No attempts yet	2s	512 MB	Judgeable
Fibonacci-like SequenceGiven n up to 116, compute the n-th term of the recurrence f(n) = f(n-1) + f(n-3) with f(1)=f(2)=f(3)=1.	Easy2	Dynamic programmingMath+1	No attempts yet	2s	512 MB	Judgeable
Bovine Genomics (Bronze)Count genome positions where the set of characters in spotty cows and the set in plain cows do not overlap.	Easy2	ImplementationBrute force+1	No attempts yet	2s	512 MB	Judgeable
Birthday GraphRead dates in dd mm yyyy form and print a star per birthday for each of the twelve months, in a numbered case format.	Easy2	ArrayString+1	No attempts yet	5s	512 MB	Judgeable
Grid PatternFor each case, print a text grid with pipe, minus, and plus lines and asterisk-filled cells of size w by h.	Easy2	ImplementationSimulation+1	No attempts yet	10s	512 MB	Judgeable
Speed LimitFor each log entry, multiply the speed by the time since the previous entry, sum these products, and print the total distance in miles.	Easy2	ImplementationMath+1	No attempts yet	5s	512 MB	Judgeable
Outer Triangle SumFor each triangle, add the first and last value of every row plus all values of the last row, counting shared corners once, and print the total.	Easy2	ImplementationArray+2	No attempts yet	10s	512 MB	Judgeable
Linear EquationFor each linear equation ax + b = c, decide whether it has no, one, or infinitely many solutions and print the root truncated to six decimals.	Easy2	MathImplementation	No attempts yet	2s	512 MB	Judgeable
X X gluedFor each registration number, print every run of two or more identical digits in the four-digit group, in left-to-right order.	Easy2	StringImplementation+1	No attempts yet	2s	512 MB	Judgeable
Card Game ContestFor each of N games, Meiji has A_i decks, or gets one basic deck if A_i is 0. Count the number of distinct ways to enter, modulo M.	Easy2	MathImplementation+2	No attempts yet	1s	256 MB	Judgeable
Perfect, deficient, or abundantFor each of T numbers below 10000, sum its proper divisors and classify it as Perfect, Deficient, or Abundant.	Easy2	MathBrute force+1	No attempts yet	1s	128 MB	Judgeable
2017 Yonsei University Programming ContestCount triples (A, B, C) with A+B+C = N, all at least 1, C at least B+2, and A even.	Easy2	Brute forceMath+1	No attempts yet	1s	128 MB	Judgeable
Hongjun surrounded by fansGiven Hongjun's id, print a 3 by 3 grid of emoticons with :id: in the center and :fan: in the other eight cells.	Easy2	ImplementationString	No attempts yet	1s	64 MB	Judgeable
We Lost Again TodayGiven the runs each team scored in all nine innings, decide whether the Ullim Geminis ever held a lead during a game they ended up losing.	Easy2	ImplementationSimulation+1	No attempts yet	1s	64 MB	Judgeable
2017 Ajou University Programming Contest (Small)Given up to three contestants' scores, submission counts, and last scoring upload times, output the number of the top-ranked contestant by the tie-break rules.	Easy2	SortingImplementation	No attempts yet	1s	512 MB	Judgeable
2017 Ajou Programming Contest (Large)Given each contestant's score, submission count, and last scoring upload time, print the number of the first-place contestant.	Easy2	Sorting	No attempts yet	1s	512 MB	Judgeable
EmpathyMultiply two binary numbers up to 30 bits long and print the product in binary without leading zeros.	Easy2	MathString+2	No attempts yet	2s	256 MB	Judgeable
Jeonbuk National UniversityPrint an ASCII symbol of width N when N is odd, following fixed spacing rules; print "I LOVE CBNU" when N is even.	Easy2	ImplementationSimulation	No attempts yet	1s	128 MB	Judgeable
Recovering a Damaged ISBN DigitOne digit of a 13-digit ISBN is replaced by '*', and you print the digit that makes the weighted checksum divisible by 10.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
I am happy~Given the height N, width M, and a seat number K in row-major order, print the row and column of that seat.	Easy2	MathImplementation+2	No attempts yet	2s	256 MB	Judgeable
Fox SignGiven up to 10 touching pairs among five fingers, decide whether the pattern matches the fox sign: thumb, middle, and ring all touch, while index and little touch nothing.	Easy2	ImplementationArray	No attempts yet	0.5s	512 MB	Judgeable