Problems

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Total results29,478 problems

Hamburger Sort
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Dartboard
Easy2
Array, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
ANA is a palindrome
Easy2
String, Brute force
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
TPS
Easy2
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Fractions are better when continued
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Dishonest Lottery
Easy2
Array, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
BB84
Easy2
Implementation, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Osobna
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Expected Error
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Composed Rhythms
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Leg Day
Easy2
String, Simulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Building Pyramids
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Dragged-out Duel
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Jumbled Scoreboards
Easy2
Array, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Expected Eyes
Easy2
Math
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Club Fund Embezzlement
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
What Is a Human
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Akaraka 2
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Sauna
Easy2
Array, Implementation
No attempts yet
Time limit
1.5s
Memory limit
1024 MB
Judgeable
Which Number Kind Is It?
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
4-LSB
Easy2
Bit manipulation, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Juta's Route
Easy2
Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Obedient Tom
Easy2
Simulation, Array
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
f(A + B)
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Hamburger
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Gahui and the 4-Hour Wall 2
Easy2
Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Gahee and the Electricity Bill 1
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Bus Assignment
Easy2
Simulation, Array
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Generalized FizzBuzz
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Ruffians
Easy2
Brute force, Implementation
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Oooh I See
Easy2
Matrix, Brute force
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Matrix Game
Easy2
Array, Implementation
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Which One is Larger
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Su-su-su-supernova
Easy2
Implementation, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
The Coin God Geonmo
Easy2
Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Consolidating Windows
Easy2
Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Alphabetical Aristocrats
Easy2
String, Sorting
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Chips
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
RACI Matrix
Easy2
Array, Implementation
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Triangle on the Axis
Easy2
Array, Implementation
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
False Alarm
Easy2
Implementation, Brute force
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Shooting Practice
Easy2
Simulation, Brute force
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Drone Control
Easy2
Simulation, Hash map
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Graphs and Graphs
Easy2
Brute force, Implementation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Bitcoin Halving
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Recollection
Easy2
Hash map, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Conference Track Registration
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Apartment
Easy2
Simulation, Array
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Waste Separation
Easy2
Implementation, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Jjin Even Number
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Anomaly Mahjong 1
Easy2
Array, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Problem C
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Dorayaki
Easy2
Brute force, Implementation
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Either, but Not Both
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Periodic String
Easy2
String, Brute force
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Hezardastan's Annual Report
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Divar's Salaries
Easy2
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Fermat's Fakini
Easy2
Implementation, Hash map
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Cake Promise
Easy2
Implementation, Array
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Glass Reflection
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Alternative Blockchain Algorithms
Easy2
Implementation, Simulation
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Encryptastrophy
Easy2
String, Simulation
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Game Night
Easy2
String, Implementation
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Defense Clock
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
I Flipped The Calendar...
Easy2
Implementation, Math
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Šah
Easy2
Implementation, Matrix+1
No attempts yet
Time limit
3s
Memory limit
2048 MB
Judgeable
Sum of a Sequence
Easy3
Math, Brute force+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Treasure
Easy3
Greedy, Sorting+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Divisors
Easy3
Math, Number theory+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Lies
Easy3
Union-find, Graph+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Guitar Strings
Easy3
Brute force, Greedy+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Number Square
Easy3
Brute force, Matrix+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Tournament Meeting Round
Easy3
Simulation, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Friends
Easy3
Graph, Matrix+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
King
Easy3
Simulation, Implementation
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Leaf Nodes in a Tree
Easy3
Tree, DFS+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Z
Easy3
Divide and conquer, Recursion+1
No attempts yet
Time limit
0.5s
Memory limit
512 MB
Judgeable
Addition Cycle
Easy3
Simulation, Math
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Minimum String Difference
Easy3
String, Sliding window+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Underprime
Easy3
Number theory, Math+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Least Common Multiple of at Least Three Numbers
Easy3
Math, Brute force+2
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
RGB Street
Easy3
Dynamic programming, Array
No attempts yet
Time limit
0.5s
Memory limit
128 MB
Judgeable
Josephus Permutation
Easy3
Queue, Simulation+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Come Back Home
Easy3
Backtracking, DFS+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Finding the Rank
Easy3
Array, Implementation+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Strange Multiplication
Easy3
Math, String+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Dice Sum
Easy3
Brute force, Math+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Student Numbers
Easy3
String, Brute force+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Castle Guards
Easy3
Array, Greedy+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Switches On and Off
Easy3
Simulation, Array+2
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Binary Addition
Easy3
String, Math+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Make a Palindrome
Easy3
String, Brute force+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
DFS and BFS
Easy3
DFS, BFS+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Alphabet Diamond
Easy3
Simulation, Math+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Symmetric Difference
Easy3
Hash map, Array+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
War - Land Grab
Easy3
Array, Hash map
No attempts yet
Time limit
10s
Memory limit
512 MB
Judgeable
Shortcut Key Assignment
Easy3
Simulation, String+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Lee-myeon and Im-hyeon
Easy3
Number theory, Implementation+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Bestseller
Easy3
Hash map, Sorting+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
D-Day
Easy3
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Hamburger SortGiven a length-3 string holding (, 1, and ) once each, find the fewest moves that place one character next to another to form (1).	Easy2	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
DartboardGiven 20 dartboard scores in circular order, print whichever of Alice (aims at 20 and its two neighbors) or Bob (averages all sectors) has the higher expected score, or Tie.	Easy2	ArrayMath	No attempts yet	1s	1024 MB	Judgeable
ANA is a palindromeCount the substrings of S that start and end with A, contain exactly one N, and have no other A.	Easy2	StringBrute force	No attempts yet	1s	1024 MB	Judgeable
TPSSimulate W, A, S, D moves and 90-degree camera rotations around the protagonist, printing both positions after each input.	Easy2	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable
Fractions are better when continuedGiven N, print the numerator of p_N, where p_0 = 1 and p_N = 1 / (1 + p_(N-1)), written in lowest terms.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Dishonest LotteryGiven 10n drawings of five distinct numbers from 1 to 50, list every number that appears more than 2n times, or print -1 if none do.	Easy2	ArrayImplementation	No attempts yet	1s	1024 MB	Judgeable
BB84Given each qubit's basis and value from both sides, build the shared key from positions where the bases match, or print htg! if any matched position disagrees.	Easy2	ImplementationString	No attempts yet	1s	1024 MB	Judgeable
OsobnaGiven three 30-character ID card lines, extract the first name, last name, birth date, and PIN, then print them in a fixed Croatian label format.	Easy2	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Expected ErrorGiven a sudo password of length n, a slip after k correct characters with probability p%, pick the strategy (continue, backspace, or restart) with the lowest expected typing time.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Composed RhythmsGiven N, the task is to split N into groups of sizes 2 and 3 that sum to exactly N and print one valid decomposition.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Leg DayClassify each day of a repeating exercise plan as rest, leg, or arm by keyword, then print a Monday-start 31-day calendar of matching pictographs over 5 weeks.	Easy2	StringSimulation+1	No attempts yet	1s	1024 MB	Judgeable
Building PyramidsGiven n, the number of spheres on one edge of a tetrahedral stack, output the total number of spheres in the pyramid.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Dragged-out DuelGiven two strings of rock-paper-scissors choices over n rounds, output whether you or Guile wins more rounds.	Easy2	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Jumbled ScoreboardsGiven n score pairs in the order the pictures arrived, check whether both teams' scores never decrease from one picture to the next.	Easy2	ArrayImplementation	No attempts yet	1s	1024 MB	Judgeable
Expected EyesGiven n dice and the number of faces on each, print the expected value of the sum when all dice are rolled at once.	Easy2	Math	No attempts yet	4s	1024 MB	Judgeable
Club Fund EmbezzlementGiven a string of at most 8 characters, decide whether it has the form n+n for a positive integer n that does not start with 0.	Easy2	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
What Is a HumanGiven N, decide whether N is a multiple of 2024 that is at most 2024 times 100000, and print Yes or No.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Akaraka 2Given K, print the shortest string in which AKARAKA appears as a contiguous substring exactly K times.	Easy2	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
SaunaFind how many temperatures lie in every person's inclusive range and the lowest such temperature, or report bad news if none exist.	Easy2	ArrayImplementation	No attempts yet	1.5s	1024 MB	Judgeable
Which Number Kind Is It?Given up to 100000 integers N up to 10^6, print O if N is odd, S if N is a perfect square, OS if both, and EMPTY otherwise.	Easy2	MathImplementation	No attempts yet	2s	1024 MB	Judgeable
4-LSBGiven three integers, take the lowest 4 bits of each, join them in order into a 12-bit number, and print it in decimal as a 4-digit password.	Easy2	Bit manipulationImplementation	No attempts yet	1s	1024 MB	Judgeable
Juta's RouteGiven three numbers from 0 to 100, decide whether they can be the first three numbers written along a left-to-right route through the figure's roads.	Easy2	Implementation	No attempts yet	1s	1024 MB	Judgeable
Obedient TomSimulate placing N colored toys into three capacity-K boxes, trying each toy's preferred box, then the next box in the A-B-C cycle when it is full.	Easy2	SimulationArray	No attempts yet	1s	1024 MB	Judgeable
f(A + B)Given a one-to-one digit mapping f and the images f(A) and f(B), compute f(A+B) for positive integers A and B up to 10^7.	Easy2	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
HamburgerGiven a string S of bread, patty, lettuce, and tomato, check whether it is a valid hamburger: bread at both ends, no equal neighbors, and counts within A, B, C, D.	Easy2	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Gahui and the 4-Hour Wall 2Given the rail time S and the flight legs Ma, Fab, and Mb, decide whether most passengers at station a take high speed rail or a flight.	Easy2	Implementation	No attempts yet	1s	512 MB	Judgeable
Gahee and the Electricity Bill 1Given a power draw of a W and a usage time of m minutes per query, compute the bill at 105.6 won per kWh, truncated to an integer.	Easy2	MathImplementation	No attempts yet	1s	512 MB	Judgeable
Bus AssignmentGiven how many people get off and get on at each stop, find the maximum number of passengers on the bus at any one time.	Easy2	SimulationArray	No attempts yet	2s	2048 MB	Judgeable
Generalized FizzBuzzGiven n, a, and b, count how many times Fizz, Buzz, and FizzBuzz are printed in a generalized FizzBuzz run from 1 to n.	Easy2	MathImplementation	No attempts yet	1s	2048 MB	Judgeable
RuffiansGiven a two-by-five grid of digits, the task is to decide whether two cards with equal numbers sit in different rows and different columns.	Easy2	Brute forceImplementation	No attempts yet	1s	2048 MB	Judgeable
Oooh I SeeGiven a grid of O and 0 characters, find every 0 whose eight neighbors are all O, then print its position, the count, or Oh no!.	Easy2	MatrixBrute force	No attempts yet	1s	2048 MB	Judgeable
Matrix GameFor each column, pick the row that maximizes \|a - b\| there, then sum those maxima over all M columns Chan calls to get the largest possible Diff.	Easy2	ArrayImplementation	No attempts yet	1s	2048 MB	Judgeable
Which One is LargerGiven two decimals, print the larger one if comparing them as integer tuples (integer part, then fraction digits) agrees with normal decimal order, otherwise print -1.	Easy2	StringImplementation	No attempts yet	1s	2048 MB	Judgeable
Su-su-su-supernovaGiven a year N and its discovery order M, print the supernova name: SN, the year, then the order written as A to Z, followed by aa to zz.	Easy2	ImplementationString	No attempts yet	1s	1024 MB	Judgeable
The Coin God GeonmoGiven a principal N and a loss percentage X, find the percentage rise needed from the reduced amount to return exactly to N.	Easy2	Math	No attempts yet	1s	1024 MB	Judgeable
Consolidating WindowsGiven two square window side lengths a and b, output the side length of one square whose area equals a squared plus b squared.	Easy2	Math	No attempts yet	1s	1024 MB	Judgeable
Alphabetical AristocratsGiven n surnames, sort them by the substring starting at the first capital letter, using ASCII order, and print the full names.	Easy2	StringSorting	No attempts yet	2s	1024 MB	Judgeable
ChipsGiven k cans with n chips each, find the minimum and maximum number of minutes that can pass before Vasiliy takes an empty can.	Easy2	MathImplementation	No attempts yet	2s	2048 MB	Judgeable
RACI MatrixCheck whether every row of a RACI matrix has exactly one A and at most one R, printing Yes or No.	Easy2	ArrayImplementation	No attempts yet	2s	2048 MB	Judgeable
Triangle on the AxisGiven integer points in the plane, find the largest-area triangle with one side on the Ox axis, or print 0 if no non-degenerate triangle exists.	Easy2	ArrayImplementation	No attempts yet	2s	2048 MB	Judgeable
False AlarmGiven n alarm times between 7:00 and 9:00, find the fewest extra alarms needed so that some three alarms fall within 10 minutes of each other.	Easy2	ImplementationBrute force	No attempts yet	2s	2048 MB	Judgeable
Shooting PracticeStarting from the cursor at (0, 0), repeatedly shoot the farthest target and sum the squared distances from the cursor to each shot target over M moves.	Easy2	SimulationBrute force	No attempts yet	1s	1024 MB	Judgeable
Drone ControlGiven obstacle cells and a string of U, D, R, L moves, find the drone's final position when it stays put whenever the next cell holds an obstacle.	Easy2	SimulationHash map	No attempts yet	1s	1024 MB	Judgeable
Graphs and GraphsGiven a line Ax + By = C, add a directed edge from x to y for every integer point (x, y) with 1 to 10 on the line, then print each vertex's out-neighbors.	Easy2	Brute forceImplementation+1	No attempts yet	1s	1024 MB	Judgeable
Bitcoin HalvingGiven the initial reward R, the halving interval K, and a block number M, print the mining reward of block M.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
RecollectionGiven N classes with student ID lists, count the students who appear in at least M of the classes.	Easy2	Hash mapImplementation	No attempts yet	1s	1024 MB	Judgeable
Conference Track RegistrationGiven a paper topic, print which conference track to join by checking which track's keyword appears in the topic.	Easy2	StringImplementation	No attempts yet	1s	2048 MB	Judgeable
ApartmentRotate a circular stack of 2N hands by each game's count and report the participant at the bottom, keeping the arrangement between games.	Easy2	SimulationArray	No attempts yet	1s	1024 MB	Judgeable
Waste SeparationFor each trash string, pick the cheaper option: its recycling bin if it is one recyclable type, otherwise general waste, and sum the minimum costs.	Easy2	ImplementationString	No attempts yet	1s	1024 MB	Judgeable
Jjin Even NumberGiven N, count the N-digit Jjin Even Numbers (no leading zero, except 0 itself) modulo 10^9+7 for up to 100,000 queries.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Anomaly Mahjong 1Given a sequence of mahjong tiles, find the position of the first tile whose kind appears a fifth time, or print 0 if no kind reaches five.	Easy2	ArrayImplementation	No attempts yet	1s	1024 MB	Judgeable
Problem CGiven N words, replace each c with k or s by its English pronunciation rule, and replace each ch with c.	Easy2	StringImplementation	No attempts yet	1s	2048 MB	Judgeable
DorayakiGiven tastiness values for N fillings and M skins, sum (a+b) times max(a,b) over every filling and skin pair.	Easy2	Brute forceImplementation	No attempts yet	2s	2048 MB	Judgeable
Either, but Not BothCount the integers from 1 to N that are divisible by exactly one of A and B.	Easy2	MathImplementation	No attempts yet	2s	2048 MB	Judgeable
Periodic StringGiven a string S of length N, the task is to check whether S is some string T repeated at least twice, printing Yes or No.	Easy2	StringBrute force	No attempts yet	2s	2048 MB	Judgeable
Hezardastan's Annual ReportGiven the page count of each chapter, find the fewest A4 sheets needed when every chapter starts on an odd page and no sheet mixes two chapters.	Easy2	MathImplementation	No attempts yet	1s	2048 MB	Judgeable
Divar's SalariesComputes each employee's monthly pay from wage x, total hours k, and holiday hours h, using 1.5x for hours past 140 and 2x for holiday hours.	Easy2	ImplementationMath	No attempts yet	1s	2048 MB	Judgeable
Fermat's FakiniGiven N nicknames split into even and odd gangs, Mirko joins the larger gang and picks the smallest unused natural number with that parity.	Easy2	ImplementationHash map	No attempts yet	1s	2048 MB	Judgeable
Cake PromiseGiven each team's per-problem solve times (X for unsolved), count the teams that solved more problems than Professor Wright, or the same number with an equal or lower total time.	Easy2	ImplementationArray	No attempts yet	2s	2048 MB	Judgeable
Glass ReflectionGiven a reflected string where each run of identical letters is one letter longer than in the original, output the original word.	Easy2	StringImplementation	No attempts yet	1s	2048 MB	Judgeable
Alternative Blockchain AlgorithmsWalk the blocks in order, check each parent id against the previous block id, and print the final balance, NO_MONEY, or INVALID.	Easy2	ImplementationSimulation	No attempts yet	1s	2048 MB	Judgeable
EncryptastrophyGiven a ciphertext where each letter is the mod 26 sum of a plaintext letter and the plaintext letter before it, plus the last plaintext letter, recover the full plaintext.	Easy2	StringSimulation	No attempts yet	1s	2048 MB	Judgeable
Game NightGiven two equal-length passwords, count the positions where the letters differ, since only those magnets must be fetched from the box.	Easy2	StringImplementation	No attempts yet	2s	2048 MB	Judgeable
Defense ClockGiven the total service days N and completed days M, print the Defense Clock time in HH:MM, where 1440 minutes span the full service period, truncated to whole minutes.	Easy2	MathImplementation	No attempts yet	2s	1024 MB	Judgeable
I Flipped The Calendar...Given a year from 1970 to 2037, count the rows the twelve monthly calendar sheets need when each week starts on Monday.	Easy2	ImplementationMath	No attempts yet	2s	2048 MB	Judgeable
ŠahCount the squares attacked by at least one knight, rook, or queen on an N by N board, where pieces attack through other pieces and their own square counts.	Easy2	ImplementationMatrix+1	No attempts yet	3s	2048 MB	Judgeable
Sum of a SequenceGiven N and a minimum length L, find the shortest run of consecutive non-negative integers summing to N, or print -1 if none exists within length 100.	Easy3	MathBrute force+1	No attempts yet	2s	128 MB	Judgeable
TreasureGiven two arrays A and B, rearrange A (B stays fixed) to minimize the sum of elementwise products, using the sorted pairing strategy.	Easy3	GreedySorting+1	No attempts yet	2s	128 MB	Judgeable
DivisorsGiven all proper divisors of an unknown number N, compute N using the fact that the smallest and largest proper divisors multiply to N.	Easy3	MathNumber theory+1	No attempts yet	2s	512 MB	Judgeable
LiesUsing union-find on party attendees, determine which parties can be exaggerated without conflicting with people who must always hear the truth.	Easy3	Union-findGraph+1	No attempts yet	2s	128 MB	Judgeable
Guitar StringsBuy at least N guitar strings using packages of 6 or single strings from M brands at given prices, minimizing total cost.	Easy3	Brute forceGreedy+1	No attempts yet	2s	128 MB	Judgeable
Number SquareGiven an N by M grid of digits, find the area of the largest axis-aligned square whose four corner cells share the same digit.	Easy3	Brute forceMatrix+1	No attempts yet	2s	128 MB	Judgeable
Tournament Meeting RoundSimulate a single-elimination tournament where positions are halved each round to find when two specific players first face each other.	Easy3	SimulationMath+1	No attempts yet	1s	512 MB	Judgeable
FriendsGiven an N x N friendship matrix (N ≤ 50), find the maximum count of people reachable within two friendship links from any single person.	Easy3	GraphMatrix+1	No attempts yet	2s	128 MB	Judgeable
KingMove a king on an 8x8 board by given commands; if it lands on the stone, the stone slides one square the same way unless it would leave the board.	Easy3	SimulationImplementation	No attempts yet	2s	128 MB	Judgeable
Leaf Nodes in a TreeGiven a tree by parent array, delete a node and all its descendants, then count how many leaf nodes remain.	Easy3	TreeDFS+1	No attempts yet	2s	128 MB	Judgeable
ZGiven N and coordinates (r,c) in a 2^N x 2^N grid, compute the visit order index of that cell under recursive Z-order (Morton order) traversal.	Easy3	Divide and conquerRecursion+1	No attempts yet	0.5s	512 MB	Judgeable
Addition CycleSimulate a digit-transformation cycle on a two-digit number until it returns to the original value and count the steps.	Easy3	SimulationMath	No attempts yet	2s	128 MB	Judgeable
Minimum String DifferenceSlide the shorter string A across every possible alignment position over B and output the minimum number of mismatched characters.	Easy3	StringSliding window+1	No attempts yet	2s	128 MB	Judgeable
UnderprimeCount integers in a range whose total number of prime factors (with multiplicity) is itself a prime number.	Easy3	Number theoryMath+1	No attempts yet	2s	128 MB	Judgeable
Least Common Multiple of at Least Three NumbersGiven five distinct positive integers up to 100, find the smallest number divisible by at least three of them, essentially the minimum LCM over all triples.	Easy3	MathBrute force+2	No attempts yet	2s	128 MB	Judgeable
RGB StreetGiven per-house costs for three colors, compute the minimum total cost to paint all houses in a line so that no two adjacent houses share a color.	Easy3	Dynamic programmingArray	No attempts yet	0.5s	128 MB	Judgeable
Josephus PermutationSimulate the Josephus elimination order for N people counting off every K-th person in a circle and print the removal sequence.	Easy3	QueueSimulation+1	No attempts yet	2s	256 MB	Judgeable
Come Back HomeCount simple paths of exact length K from the bottom-left to the top-right cell of a small grid, avoiding blocked cells and revisits.	Easy3	BacktrackingDFS+1	No attempts yet	2s	128 MB	Judgeable
Finding the RankGiven a sorted list of scores with a capacity limit, compute the rank of a new score or return -1 if the list is full and the score is not higher than the last entry.	Easy3	ArrayImplementation+1	No attempts yet	2s	128 MB	Judgeable
Strange MultiplicationGiven two large numbers as digit strings, compute the sum of all pairwise products of their digits, which equals the product of their digit sums.	Easy3	MathString+1	No attempts yet	2s	256 MB	Judgeable
Dice SumGiven three dice with sizes S1, S2, S3, find the sum value that occurs most often among all possible triples, choosing the smallest if tied.	Easy3	Brute forceMath+1	No attempts yet	2s	128 MB	Judgeable
Student NumbersGiven N equal-length numeric strings, find the smallest suffix length k so that all suffixes of length k remain distinct.	Easy3	StringBrute force+1	No attempts yet	2s	128 MB	Judgeable
Castle GuardsGiven a grid of guards, compute the minimum number of guards to add so every row and column has at least one, which equals the max of empty-row count and empty-column count.	Easy3	ArrayGreedy+1	No attempts yet	2s	128 MB	Judgeable
Switches On and OffSimulate switch toggles where male students flip every multiple of their number and female students flip the largest symmetric interval centered on their number.	Easy3	SimulationArray+2	No attempts yet	2s	128 MB	Judgeable
Binary AdditionAdd two binary strings up to 80 digits long and print the sum in binary without leading zeros.	Easy3	StringMath+1	No attempts yet	2s	128 MB	Judgeable
Make a PalindromeGiven a lowercase string of length at most 50, find the minimum length of a palindrome obtained by appending characters only to its end.	Easy3	StringBrute force+1	No attempts yet	2s	128 MB	Judgeable
DFS and BFSGiven an undirected graph, output the vertex visit order for DFS then BFS starting from a given vertex, always preferring the smallest-numbered neighbor.	Easy3	DFSBFS+1	No attempts yet	2s	128 MB	Judgeable
Alphabet DiamondGiven a repeating diamond-pattern tile defined by N, print the characters inside a specified rectangular region of the infinite tiled plane.	Easy3	SimulationMath+1	No attempts yet	2s	128 MB	Judgeable
Symmetric DifferenceGiven two sets of natural numbers, compute the size of their symmetric difference.	Easy3	Hash mapArray+1	No attempts yet	2s	256 MB	Judgeable
War - Land GrabFor each region's list of soldier army IDs, find the majority element that appears more than half the time, or print SYJKGW if none exists.	Easy3	ArrayHash map	No attempts yet	10s	512 MB	Judgeable
Shortcut Key AssignmentAssign each menu option an unused shortcut letter by checking word-initial letters first, then any letter in the string, following the options in order.	Easy3	SimulationString+1	No attempts yet	2s	128 MB	Judgeable
Lee-myeon and Im-hyeonClassify a number 1 to 2700 as Lee-myeon and/or Im-hyeon based on digit sum parity and prime factorization rules, then output one of four codes.	Easy3	Number theoryImplementation+1	No attempts yet	2s	128 MB	Judgeable
BestsellerGiven N book titles sold in a day, find the most frequent title, breaking ties by lexicographically smallest.	Easy3	Hash mapSorting+1	No attempts yet	2s	128 MB	Judgeable
D-DayCompute the number of days between two calendar dates accounting for leap years, printing 'gg' if the gap reaches 1000 years or more.	Easy3	MathImplementation	No attempts yet	2s	128 MB	Judgeable