Problems

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Total results21,417 problems

#include <Google I/O.h>Easy2
Implementation, String +1No attempts yetTime limit5sMemory limit512 MB
Judgeable
Dreary Design (Small)Easy2
Brute force, MathNo attempts yetTime limit5sMemory limit512 MB
Judgeable
GBus Count (Small)Easy2
Brute force, IntervalsNo attempts yetTime limit5sMemory limit512 MB
Judgeable
GBus Count (Large)Easy2
Brute force, Intervals +1No attempts yetTime limit5sMemory limit512 MB
Judgeable
New Lottery Game (Small)Easy2
Brute force, Bit manipulationNo attempts yetTime limit5sMemory limit512 MB
Judgeable
Read Phone Number (Small)Easy2
Simulation, String +1No attempts yetTime limit5sMemory limit512 MB
Judgeable
Tic-Tac-Toe-Tomek (Small)Easy2
Implementation, MatrixNo attempts yetTime limit5sMemory limit512 MB
Judgeable
Tic-Tac-Toe-Tomek (Large)Easy2
Implementation, Brute force +1No attempts yetTime limit5sMemory limit512 MB
Judgeable
Fair and Square (Small)Easy2
Brute force, Math +1No attempts yetTime limit5sMemory limit512 MB
Judgeable
Proprietary ProblemEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Hedgemony (Small)Easy2
Simulation, MathNo attempts yetTime limit5sMemory limit512 MB
Judgeable
Dr. Spaceman's height algorithmEasy2
Implementation, MathNo attempts yetTime limit5sMemory limit512 MB
Judgeable
Quake Live (Small2)Easy2
Brute force, CombinatoricsNo attempts yetTime limit5sMemory limit512 MB
Judgeable
Card Shuffle (Small)Easy2
Simulation, ArrayNo attempts yetTime limit5sMemory limit512 MB
Judgeable
Program within a Program (Small)Easy2
ImplementationNo attempts yetTime limit5sMemory limit512 MB
Judgeable
Investing at the MarketEasy2
Brute force, ArrayNo attempts yetTime limit5sMemory limit512 MB
Judgeable
Investing at the Market (Large)Easy2
Brute forceNo attempts yetTime limit5sMemory limit512 MB
Judgeable
Odd Man OutEasy2
Bit manipulation, Array +1No attempts yetTime limit5sMemory limit512 MB
Judgeable
Reverse Word OrderEasy2
String, ImplementationNo attempts yetTime limit5sMemory limit512 MB
Judgeable
Reverse Words (Large)Easy2
String, ImplementationNo attempts yetTime limit5sMemory limit512 MB
Judgeable
T9 Spelling (Small)Easy2
String, Implementation +2No attempts yetTime limit5sMemory limit512 MB
Judgeable
Immigrate to the CTP principalityEasy2
Implementation, String +2No attempts yetTime limit1sMemory limit128 MB
Judgeable
Tojaengi's Walk to SchoolEasy2
Combinatorics, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Mini Fantasy WarEasy2
Implementation, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
StarmanEasy2
Array, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Bitwise Operations on Binary NumbersEasy2
String, Bit manipulation +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
XORXORXOREasy2
Bit manipulation, MathNo attempts yetTime limit0.2sMemory limit512 MB
Judgeable
Changyong's ClockEasy2
Simulation, Math +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
LobbyEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
CamerasEasy2
String, Implementation +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Three SumsEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
FormulaEasy2
Geometry, Math +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Adding god to nicknamesEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Router 4Easy2
Implementation, SimulationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Manhattan TaxiEasy2
Implementation, Brute force +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
MatchesEasy2
Geometry, Math +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Chop CupEasy2
Simulation, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Divisor CountEasy2
Number theory, Brute forceNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Tic Tac ToeEasy2
Implementation, Matrix +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
The real Manhattan distanceEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
PalindromeEasy2
String, Two pointers +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Collatz SequenceEasy2
Simulation, Implementation +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
ChessboardEasy2
Array, Implementation +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
Least Common MultipleEasy2
Math, Number theory +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
A New AlphabetEasy2
String, Hash map +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Quick EstimatesEasy2
String, Math +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Room AssignmentEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Jumbled CompassEasy2
Math, Implementation +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Math ContestEasy2
Number theory, Math +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Stock InvestmentEasy2
Array, GreedyNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Four Arithmetic OperationsEasy2
Math, Implementation +2No attempts yetTime limit1sMemory limit128 MB
Judgeable
Graph Maximum MatchingEasy2
Graph, Backtracking +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
László BabaiEasy2
Graph, Brute force +1No attempts yetTime limit1sMemory limit256 MB
Judgeable
Anniversary CakeEasy2
Geometry, Implementation +1No attempts yetTime limit2sMemory limit256 MB
Judgeable
Boys and GirlsEasy2
Implementation, Brute force +1No attempts yetTime limit2sMemory limit256 MB
Judgeable
Data PlanEasy2
Implementation, MathNo attempts yetTime limit1sMemory limit64 MB
Judgeable
Cleaning StationsEasy2
Implementation, Array +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Walking in timeEasy2
Brute force, Math +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
The Funniest Digital LaughterEasy2
String, Two pointersNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Dangerous DiveEasy2
Array, Hash mapNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Lost BootsEasy2
Hash map, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Optical mark readingEasy2
Implementation, Brute forceNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Alarm ClockEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Sub-primeEasy2
Array, Implementation +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Dividing NlogôniaEasy2
Implementation, MathNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Pokemon GOEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit32 MB
Judgeable
Second Cheapest PresentEasy2
Sorting, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
HolesEasy2
String, Implementation +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
Olympic GamesEasy2
Implementation, MathNo attempts yetTime limit2sMemory limit512 MB
Judgeable
VirusEasy2
String, Simulation +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Alpha PuzzleEasy2
Simulation, String +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Splitting into Two TeamsEasy2
Brute force, Math +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Farm robot scarecrowEasy2
Simulation, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Unit ConversionEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Magic SquaresEasy2
Implementation, MatrixNo attempts yetTime limit2sMemory limit512 MB
Judgeable
FuelEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Luhn AlgorithmEasy2
String, Implementation +2No attempts yetTime limit1sMemory limit512 MB
Judgeable
TelephoneEasy2
Math, Implementation +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Enlarging the Cow SignalEasy2
Implementation, ArrayNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Income taxEasy2
Implementation, MathNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Key MakerEasy2
Array, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
GradesEasy2
Array, Math +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Bridge Honor PointsEasy2
Implementation, String +1No attempts yetTime limit1sMemory limit32 MB
Judgeable
Sitting (Small)Easy2
Brute force, ImplementationNo attempts yetTime limit5sMemory limit512 MB
Judgeable
Country Leader (Small)Easy2
String, Implementation +2No attempts yetTime limit5sMemory limit512 MB
Judgeable
Country LeaderEasy2
String, Sorting +2No attempts yetTime limit5sMemory limit512 MB
Judgeable
Counting Sheep (Large)Easy2
Math, Simulation +1No attempts yetTime limit5sMemory limit512 MB
Judgeable
String SetEasy2
Hash mapNo attempts yetTime limit2sMemory limit1536 MB
Judgeable
MicrowaveEasy2
Math, Implementation +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Refreshment AreaEasy2
Array, Implementation +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
One Hundred to TenEasy2
Math, Number theory +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Base 9Easy2
Math, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Fibonacci-like SequenceEasy2
Dynamic programming, Math +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Bovine Genomics (Bronze)Easy2
Implementation, Brute force +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Birthday GraphEasy2
Array, String +1No attempts yetTime limit5sMemory limit512 MB
Judgeable
Grid PatternEasy2
Implementation, Simulation +1No attempts yetTime limit10sMemory limit512 MB
Judgeable
Speed LimitEasy2
Implementation, Math +1No attempts yetTime limit5sMemory limit512 MB
Judgeable
Outer Triangle SumEasy2
Implementation, Array +2No attempts yetTime limit10sMemory limit512 MB
Judgeable
Linear EquationEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
X X gluedEasy2
String, Implementation +1No attempts yetTime limit2sMemory limit512 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
#include <Google I/O.h>Decode each block of eight I and O letters as one ASCII byte and print the message for every test case.	Easy2	ImplementationString+1	No attempts yet	5s	512 MB	Judgeable
Dreary Design (Small)Count RGB triples with each component in 0 to K whose largest and smallest values differ by at most V.	Easy2	Brute forceMath	No attempts yet	5s	512 MB	Judgeable
GBus Count (Small)Count, for each queried city, how many of the given inclusive ranges cover it.	Easy2	Brute forceIntervals	No attempts yet	5s	512 MB	Judgeable
GBus Count (Large)Count, for each queried city, how many of the given inclusive intervals cover it.	Easy2	Brute forceIntervals+1	No attempts yet	5s	512 MB	Judgeable
New Lottery Game (Small)Count pairs (a, b) with a below A and b below B whose bitwise AND is below K.	Easy2	Brute forceBit manipulation	No attempts yet	5s	512 MB	Judgeable
Read Phone Number (Small)Split each digit string into the given group lengths and read each run of equal digits with count words such as double and triple.	Easy2	SimulationString+1	No attempts yet	5s	512 MB	Judgeable
Tic-Tac-Toe-Tomek (Small)Given a 4 by 4 tic-tac-toe board with a wildcard T, report whether X won, O won, the game is a draw, or play continues.	Easy2	ImplementationMatrix	No attempts yet	5s	512 MB	Judgeable
Tic-Tac-Toe-Tomek (Large)Given a 4x4 tic-tac-toe board with a wildcard T, report whether X won, O won, the game is a draw, or play continues.	Easy2	ImplementationBrute force+1	No attempts yet	5s	512 MB	Judgeable
Fair and Square (Small)Count numbers in each interval [A, B] that are palindromes and squares of palindromes.	Easy2	Brute forceMath+1	No attempts yet	5s	512 MB	Judgeable
Proprietary ProblemA product key entry field is shown; the task appears to require validating or generating a key in the format XXXXX-XXXXX-XXXXX-XXXXX-XXXXX.	Easy2	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Hedgemony (Small)Simulate a single left-to-right pass that trims each bush to the average of its current neighbors and output the final height of bush N-1.	Easy2	SimulationMath	No attempts yet	5s	512 MB	Judgeable
Dr. Spaceman's height algorithmCompute a child height range from both parents' heights and the child sex, then round both ends inward to whole inches.	Easy2	ImplementationMath	No attempts yet	5s	512 MB	Judgeable
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