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Total results2,362 problems

Main Hall Booking
Easy1
Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Fence Construction
Easy1
Implementation, Math
No attempts yet
Time limit
0.1s
Memory limit
1024 MB
Judgeable
Platform Depth
Easy1
Prefix sum, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
See You Next Month
Easy1
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
CodeMaster 2024
Easy1
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
A + B
Easy1
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Most Likely Data Type
Easy1
Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Late Students
Easy1
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Barcode Nickname
Easy1
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Build the String
Easy1
String, String matching
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Farmers' Market
Easy1
Math, Implementation
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Basketball Score
Easy1
Implementation, Math
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Christmas Tree Adapter
Easy1
Math, Implementation
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Conveyor Belt Sushi
Easy1
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Wow and Queries
Easy1
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Hat Circle
Easy1
Array, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Love is Korea University
Easy1
Implementation, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Attention to the Meeting
Easy1
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Just Round Down
Easy1
String, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Call for Problems
Easy1
Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Let's Play Billiards Already
Easy1
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Airfare Grants
Easy1
Array, Sorting
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Janggi
Easy1
Implementation, Math
No attempts yet
Time limit
0.3s
Memory limit
1024 MB
Judgeable
Linear Expression
Easy1
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Multiplication Table
Easy1
Brute force, Implementation
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Gahui and the 4-Hour Wall 1
Easy1
Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Gahui and Seoul Subway Line 2
Easy1
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Gahee and the Sub-station Name
Easy1
String
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Intuitive Elements
Easy1
String, Hash map
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Application List
Easy1
String, Implementation
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
UOS String
Easy1
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Why did you book it without asking
Easy1
Implementation, Array
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
AI Leading University
Easy1
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Oh Right, Garlic
Easy1
Hash map, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Alea Iacta Est
Easy1
Implementation, Math
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Pencils 2
Easy1
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Walking
Easy1
Simulation, Math
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
OIJ
Easy1
String, Simulation
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Footrace
Easy1
Implementation
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Railway Trip 3
Easy1
Implementation, Math
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Triangle Addition
Easy1
Simulation, Implementation
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Money On Me
Easy1
Implementation, Math
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Blackjack
Easy1
Implementation, Math
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Micromasters
Easy1
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Yalda
Easy1
Implementation
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Command Prompt
Easy2
String, Implementation
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Hansu Numbers
Easy2
Implementation, Brute force+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Make It Divisible
Easy2
Brute force, Math+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
White Squares
Easy2
Array, Implementation+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Word Count
Easy2
String, Implementation
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Most Frequent Letter
Easy2
Hash map, String+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Basketball Game
Easy2
Hash map, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Word Sorting
Easy2
Sorting, String
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Octal to Binary
Easy2
String, Implementation+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Sign of Integer Sums
Easy2
Implementation, Math
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Splitting a Word
Easy2
String, Brute force+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Mobile Phone Bill
Easy2
Simulation, Implementation+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
House Number Sign
Easy2
Implementation, String+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Easy Sequence Sum
Easy2
Math, Simulation+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Choosing a Team Name
Easy2
String, Implementation+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
TV Size
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Group Word Checker
Easy2
String, Implementation
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Year Progress Bar
Easy2
Implementation, Math
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Actual Disk Space
Easy2
Math, Implementation+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Yujin Number
Easy2
String, Brute force+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Reversed Addition
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Pet
Easy2
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Most Frequent Letters
Easy2
Hash map, String+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Earrings
Easy2
Hash map, Array+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Floor Decoration
Easy2
Matrix, Implementation+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Song Scores
Easy2
Prefix sum, Binary search+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
24-Hour Mission
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Sort Digits Descending
Easy2
Sorting, String+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Organizing Books
Easy2
Simulation, Implementation+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Time Machine
Easy2
Combinatorics, Brute force+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Internet Cafe Seat Requests
Easy2
Simulation, Array+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Room Number
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Adjusted Average
Easy2
Array, Math+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Ball
Easy2
Simulation, Implementation
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Sequence Transformation
Easy2
Array, Simulation+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Manhattan Distance on a Four-Row Number Board
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Find Places to Lie Down
Easy2
Matrix, Simulation
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Trophy Display
Easy2
Array, Implementation
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Chicken Coupons
Easy2
Math, Simulation+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Growth Points
Easy2
Simulation, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Break-Even Point
Easy2
Math, Implementation
No attempts yet
Time limit
0.35s
Memory limit
128 MB
Judgeable
Next Term in a Sequence
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Fraction Sum
Easy2
Math, Number theory+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Concatenating Numbers 1
Easy2
Math, Implementation
No attempts yet
Time limit
0.15s
Memory limit
128 MB
Judgeable
Packing Books into Boxes
Easy2
Greedy, Array+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Numbers With Equal Remainder and Quotient
Easy2
Math
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Octopus Numbers
Easy2
String, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Good License Plates
Easy2
String, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Fourth Point
Easy2
Geometry, Math+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Making Anagrams
Easy2
Hash map, String
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Year 2007
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Least Common Multiple
Easy2
Math, Number theory
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Counting Pentagon Points
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Perfect Squares
Easy2
Math, Brute force+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Counting Primes
Easy2
Math, Brute force
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Main Hall BookingGiven the applicant count for each of seven seminars, print the name of the seminar with the most applicants.	Easy1	Implementation	No attempts yet	1s	1024 MB	Judgeable
Fence ConstructionGiven N rectangles added one at a time, print the perimeter of the bounding rectangle of all buildings so far after each addition.	Easy1	ImplementationMath	No attempts yet	0.1s	1024 MB	Judgeable
Platform DepthFor each station i, print the ground height minus the platform height, which is the prefix sum of A minus the prefix sum of B up to i.	Easy1	Prefix sumImplementation	No attempts yet	1s	1024 MB	Judgeable
See You Next MonthGiven Q events where setters add problems to the forum and contests use problems, determine whether any contest finds too few unused problems.	Easy1	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable
CodeMaster 2024Given n, m, and k, print the total of Doohoon's m installs on each of k computers plus Teacher Cha's m installs on the laptop.	Easy1	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
A + BRead two integers A and B from 0 to 100 and print their sum.	Easy1	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Most Likely Data TypeGiven an integer N, print the smallest type among short, int, and long long that can hold N exactly.	Easy1	Implementation	No attempts yet	1s	1024 MB	Judgeable
Late StudentsCount the students who arrive at or after the start time and not before the teacher, since they are caught and must clean the classroom.	Easy1	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable
Barcode NicknameGiven a string of only 'l' and 'I', the task is to flip the case of each character and print the result.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Build the StringGiven a string of length N up to 10, the task is to check whether the substring gori appears in it and print YES or NO.	Easy1	StringString matching	No attempts yet	1s	1024 MB	Judgeable
Farmers' MarketGiven apples per bag, number of bags, and the price per dozen, the task is to compute the cost when partial dozens are charged as full dozens.	Easy1	MathImplementation	No attempts yet	5s	1024 MB	Judgeable
Basketball ScoreGiven the free throw, 2 pointer, and 3 pointer counts for two teams, the task is to print 1, 2, or 0 for the team with more points or a tie.	Easy1	ImplementationMath	No attempts yet	5s	1024 MB	Judgeable
Christmas Tree AdapterGiven a tree's ampere and an adapter's watt and volt, the task is to print 1 if the adapter's ampere (watt divided by volt) is at least the tree's ampere, otherwise 0.	Easy1	MathImplementation	No attempts yet	5s	1024 MB	Judgeable
Conveyor Belt SushiGiven counts of red, green, and blue plates, the task is to compute the total cost at $3, $4, and $5 per plate.	Easy1	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Wow and QueriesGiven Q strings made of W and O, count how many times the substring WOW appears in each one.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Hat CircleGiven N people in a circle with hat numbers, count how many people have the same hat number as the person directly across from them.	Easy1	ArrayImplementation	No attempts yet	1s	1024 MB	Judgeable
Love is Korea UniversityGiven N from 1 to 10, print the string LoveisKoreaUniversity N times on one line, separated by spaces.	Easy1	ImplementationString	No attempts yet	1s	1024 MB	Judgeable
Attention to the MeetingGiven N speeches of equal length with 1-minute gaps between them and a K-minute limit, find the longest speech length that keeps the meeting within K.	Easy1	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Just Round DownGiven a positive decimal number as text, print its floor, the greatest integer not exceeding it.	Easy1	StringImplementation	No attempts yet	2s	1024 MB	Judgeable
Call for ProblemsGiven n difficulty ratings, count how many of them are odd numbers.	Easy1	Implementation	No attempts yet	1s	1024 MB	Judgeable
Let's Play Billiards AlreadyGiven N rain flags, anger rises by 1 on rainy days and falls by 1 otherwise, starting from 0. Print the sum of the anger over all N days.	Easy1	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable
Airfare GrantsGiven N flight prices, report the maximum price as the limit and buy the minimum, then output the net cost after the sponsors pay the lesser of the cost and half the limit.	Easy1	ArraySorting	No attempts yet	1s	1024 MB	Judgeable
JanggiGiven each side's remaining janggi pieces, decide which player has the higher score, with Han receiving a 1.5-point bonus, and print that player's name.	Easy1	ImplementationMath	No attempts yet	0.3s	1024 MB	Judgeable
Linear ExpressionGiven integers A and B, the task prints the linear expression Ax+B in standard form, dropping zero terms and coefficients of 1.	Easy1	ImplementationMath	No attempts yet	1s	1024 MB	Judgeable
Multiplication TableGiven N from 1 to 100, the task is to print 1 if N appears as a factor or product in the 2 to 9 multiplication tables, otherwise 0.	Easy1	Brute forceImplementation	No attempts yet	0.5s	1024 MB	Judgeable
Gahui and the 4-Hour Wall 1Given the rail time S and flight time F from station a to station b, decide which mode people take, where flights are chosen only when strictly faster.	Easy1	Implementation	No attempts yet	1s	512 MB	Judgeable
Gahui and Seoul Subway Line 2For each query, the task compares when inner and outer circle trains leaving station a arrive at station b on the circular Line 2 and reports the faster direction.	Easy1	ImplementationMath	No attempts yet	1s	512 MB	Judgeable
Gahee and the Sub-station NameGiven one line with a station name and an optional sub-station name in parentheses, print the station name and the sub-station name, or '-' if there is none.	Easy1	String	No attempts yet	1s	512 MB	Judgeable
Intuitive ElementsGiven two lowercase strings, the task checks whether every letter in the abbreviation b also appears somewhere in the name a, printing YES or NO for each test case.	Easy1	StringHash map	No attempts yet	1s	2048 MB	Judgeable
Application ListGiven up to 100 lowercase program names, print a 5-row grid showing which letters a to z start at least one name, with dots for missing letters.	Easy1	StringImplementation	No attempts yet	2s	2048 MB	Judgeable
UOS StringGiven a 1-based position x, print the character at that position in the infinite repeating string UOSUOS..., which follows from x modulo 3.	Easy1	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Why did you book it without askingGiven each member's list of attendable periods, the task is to check whether the reserved period X is in every list.	Easy1	ImplementationArray	No attempts yet	1s	1024 MB	Judgeable
AI Leading UniversityGiven a year N between 2024 and 9999, the task is to print how many years have passed since 2024, which is N minus 2024.	Easy1	ImplementationMath	No attempts yet	1s	1024 MB	Judgeable
Oh Right, GarlicGiven the full list of N ingredients and N-1 used ones, the task is to print the single ingredient that is missing from the second list.	Easy1	Hash mapString	No attempts yet	1s	1024 MB	Judgeable
Alea Iacta EstGiven two dice rolls for zuodong and then jiadong among four seated players, the task is to print the number of the player who becomes zhendong.	Easy1	ImplementationMath	No attempts yet	0.5s	1024 MB	Judgeable
Pencils 2Given A yen, find how many pencils costing 5 yen each JOI can buy, which is A divided by 5 rounded down.	Easy1	MathImplementation	No attempts yet	2s	2048 MB	Judgeable
WalkingGiven X, compute the net forward distance after X alternating moves of 3 m forward (A) and 2 m backward (B), starting with A.	Easy1	SimulationMath	No attempts yet	2s	2048 MB	Judgeable
OIJGiven a string of J, O, and I, shift each letter forward in the cycle J to O, O to I, I to J and print the result.	Easy1	StringSimulation	No attempts yet	2s	2048 MB	Judgeable
FootraceGiven a running speed V m per second and a time T in seconds, print the distance run in meters.	Easy1	Implementation	No attempts yet	2s	2048 MB	Judgeable
Railway Trip 3Given a trip length Q km, a rate A yen per km for the first P km, and B yen per km after that, the task is to print the total fare.	Easy1	ImplementationMath	No attempts yet	2s	2048 MB	Judgeable
Triangle AdditionGiven a sequence, the task repeatedly sums adjacent pairs to build a triangle and prints each row of the triangle.	Easy1	SimulationImplementation	No attempts yet	2s	2048 MB	Judgeable
Money On MeGiven counts of 1000-yen and 10000-yen bills, the task is to print the total amount of money in yen.	Easy1	ImplementationMath	No attempts yet	2s	2048 MB	Judgeable
BlackjackGiven three integers from 1 to 13, the task prints 1 if their sum is 21 or less, and 0 otherwise.	Easy1	ImplementationMath	No attempts yet	2s	2048 MB	Judgeable
MicromastersGiven the number of students Mina referred, each adding a 10% discount, find how many courses she can take for free.	Easy1	MathImplementation	No attempts yet	1s	2048 MB	Judgeable
YaldaGiven a budget and three prices, the task is to print the first item in the preference list (watermelon, pomegranates, nuts) that the budget covers, or Nothing.	Easy1	Implementation	No attempts yet	1s	2048 MB	Judgeable
Command PromptGiven N equal-length file names, output a pattern where each position is the common character if all names agree there, or a question mark otherwise.	Easy2	StringImplementation	No attempts yet	2s	128 MB	Judgeable
Hansu NumbersCount integers from 1 to N (N up to 1000) whose digits form an arithmetic sequence.	Easy2	ImplementationBrute force+1	No attempts yet	2s	128 MB	Judgeable
Make It DivisibleFind the smallest two-digit replacement (00-99) for the last two digits of N that makes N divisible by F.	Easy2	Brute forceMath+1	No attempts yet	2s	128 MB	Judgeable
White SquaresGiven an 8x8 board marked with pieces and empty cells, count how many pieces sit on the white squares of the standard alternating coloring.	Easy2	ArrayImplementation+1	No attempts yet	2s	128 MB	Judgeable
Word CountCount the number of space-separated words in a string that may have leading or trailing spaces.	Easy2	StringImplementation	No attempts yet	2s	128 MB	Judgeable
Most Frequent LetterCount letter frequencies in a string, case-insensitively, and print the most common letter in uppercase or a question mark on ties.	Easy2	Hash mapString+1	No attempts yet	2s	128 MB	Judgeable
Basketball GameGiven N surnames, count first letters and print all letters (in order) that start at least five surnames, or PREDAJA if none does.	Easy2	Hash mapImplementation+1	No attempts yet	1s	128 MB	Judgeable
Word SortingDeduplicate a list of words and sort them first by length, then lexicographically.	Easy2	SortingString	No attempts yet	2s	256 MB	Judgeable
Octal to BinaryConvert a huge octal number (up to 333,334 digits) into its binary representation without leading zeros.	Easy2	StringImplementation+1	No attempts yet	1s	256 MB	Judgeable
Sign of Integer SumsFor three separate lists of integers, compute each sum and print whether it is positive, negative, or zero, handling values up to 64-bit signed range.	Easy2	ImplementationMath	No attempts yet	2s	256 MB	Judgeable
Splitting a WordSplit a lowercase word into three nonempty parts, reverse each part, and find the lexicographically smallest concatenation among all splits.	Easy2	StringBrute force+1	No attempts yet	2s	128 MB	Judgeable
Mobile Phone BillGiven up to 20 call durations, compute total cost under two per-block billing plans and print the cheaper one with its cost.	Easy2	SimulationImplementation+1	No attempts yet	2s	128 MB	Judgeable
House Number SignCompute the total width of a house-number sign given fixed per-digit widths and 1 cm margins between digits and at both ends, for each input number until 0 appears.	Easy2	ImplementationString+1	No attempts yet	1s	128 MB	Judgeable
Easy Sequence SumGiven a sequence where each integer k repeats k times, compute the sum of terms between positions A and B.	Easy2	MathSimulation+1	No attempts yet	2s	128 MB	Judgeable
Choosing a Team NameCount letters L,O,V,E across a fixed name plus each candidate string, compute a formula mod 100, and print the candidate with the highest value, breaking ties by lexicographic order.	Easy2	StringImplementation+1	No attempts yet	2s	128 MB	Judgeable
TV SizeGiven a TV's diagonal length and height-to-width ratio, compute the actual height and width, flooring non-integer results.	Easy2	MathImplementation	No attempts yet	2s	128 MB	Judgeable
Group Word CheckerCount how many of up to 100 lowercase words have every repeated character forming a single contiguous block.	Easy2	StringImplementation	No attempts yet	2s	128 MB	Judgeable
Year Progress BarGiven a date and time string, compute what percentage of the current year (accounting for leap years) has elapsed.	Easy2	ImplementationMath	No attempts yet	2s	128 MB	Judgeable
Actual Disk SpaceGiven N file sizes and a cluster size, compute total disk space used by rounding each file up to the nearest cluster multiple and summing.	Easy2	MathImplementation+1	No attempts yet	2s	128 MB	Judgeable
Yujin NumberGiven an integer up to about 2.1 billion, determine whether some split of its digits into a left and right part yields equal digit products.	Easy2	StringBrute force+1	No attempts yet	2s	128 MB	Judgeable
Reversed AdditionReverse the digits of two numbers up to 1000, add the reversed values, then reverse the sum and print the result.	Easy2	MathImplementation	No attempts yet	2s	128 MB	Judgeable
PetSimulate feeding and exercising a pet's weight across scenarios and report whether it ends happy, sad, or dead based on simple weight thresholds.	Easy2	SimulationImplementation	No attempts yet	1s	128 MB	Judgeable
Most Frequent LettersCount lowercase letter frequencies across up to 50 lines of text and print all letters tied for the highest frequency in alphabetical order.	Easy2	Hash mapString+1	No attempts yet	2s	128 MB	Judgeable
EarringsGiven girl names and 2n-1 confiscation/return records tagged with a number and a letter, find the girl whose number appears only once and thus never got her earring back.	Easy2	Hash mapArray+1	No attempts yet	1s	128 MB	Judgeable
Floor DecorationCount the number of wooden planks by counting maximal runs of consecutive '-' in each row and '\|' in each column of a grid.	Easy2	MatrixImplementation+1	No attempts yet	2s	128 MB	Judgeable
Song ScoresGiven cumulative durations of N song scores, answer Q queries asking which score is being sung at a given time using prefix sums and search.	Easy2	Prefix sumBinary search+1	No attempts yet	2s	128 MB	Judgeable
24-Hour MissionGiven the current time and a start time in HH:MM:SS, compute the time remaining until the start time next occurs within a 24-hour cycle.	Easy2	MathImplementation	No attempts yet	2s	128 MB	Judgeable
Sort Digits DescendingRearrange the digits of a given natural number so they appear in descending order and print the result.	Easy2	SortingString+1	No attempts yet	2s	128 MB	Judgeable
Organizing BooksSimulate packing books into boxes in order, sealing a box once the next book no longer fits, and sum the leftover capacity of every box.	Easy2	SimulationImplementation+1	No attempts yet	2s	128 MB	Judgeable
Time MachineGiven three two-digit numbers from a digital clock, count how many of the 6 permutations form a valid HH:MM:SS time.	Easy2	CombinatoricsBrute force+1	No attempts yet	2s	128 MB	Judgeable
Internet Cafe Seat RequestsGiven a sequence of seat requests for 100 computers, count how many requests are rejected because the requested seat is already taken.	Easy2	SimulationArray+1	No attempts yet	2s	128 MB	Judgeable
Room NumberGiven a room number, count how many plastic digit sets (0-9 each) are needed, treating 6 and 9 as interchangeable when flipped.	Easy2	MathImplementation	No attempts yet	2s	128 MB	Judgeable
Adjusted AverageGiven N exam scores, rescale each by dividing by the maximum score and multiplying by 100, then output the average of the rescaled scores.	Easy2	ArrayMath+1	No attempts yet	2s	128 MB	Judgeable
BallTrack which of three cups covers a ball as cups swap positions M times, then output the cup number holding it.	Easy2	SimulationImplementation	No attempts yet	2s	128 MB	Judgeable
Sequence TransformationRepeatedly replace a sequence with its adjacent differences K times and print the resulting shorter sequence.	Easy2	ArraySimulation+1	No attempts yet	2s	128 MB	Judgeable
Manhattan Distance on a Four-Row Number BoardGiven two numbers placed column by column in a 4-row grid, compute the Manhattan distance between their cell positions.	Easy2	MathImplementation	No attempts yet	2s	128 MB	Judgeable
Find Places to Lie DownCount maximal horizontal and vertical runs of at least two consecutive empty cells in an N x N grid.	Easy2	MatrixSimulation	No attempts yet	2s	128 MB	Judgeable
Trophy DisplayCount how many trophies form a visible prefix-maximum sequence when scanning the row from the left and separately from the right.	Easy2	ArrayImplementation	No attempts yet	2s	128 MB	Judgeable
Chicken CouponsGiven n chicken coupons and a stamp-to-coupon exchange rate k, compute the maximum chickens obtainable by repeatedly redeeming stamps for new coupons.	Easy2	MathSimulation+1	No attempts yet	2s	128 MB	Judgeable
Growth PointsSimulate a tree that multiplies its leaves by a yearly factor then subtracts pruned branches, and report the final leaf count.	Easy2	SimulationMath	No attempts yet	1s	128 MB	Judgeable
Break-Even PointGiven fixed cost A, variable cost B, and price C, find the smallest number of laptops where revenue exceeds total cost, or -1 if impossible.	Easy2	MathImplementation	No attempts yet	0.35s	128 MB	Judgeable
Next Term in a SequenceGiven a sequence that is either arithmetic or geometric, determine which type it is and output its next term.	Easy2	MathImplementation	No attempts yet	2s	128 MB	Judgeable
Fraction SumAdd two given fractions and output the sum reduced to lowest terms using GCD.	Easy2	MathNumber theory+1	No attempts yet	2s	128 MB	Judgeable
Concatenating Numbers 1Compute the total digit count when integers from 1 to N are written consecutively without spaces.	Easy2	MathImplementation	No attempts yet	0.15s	128 MB	Judgeable
Packing Books into BoxesGiven book weights in order and a per-box weight limit, compute the minimum number of boxes needed by greedily filling each box in sequence.	Easy2	GreedyArray+1	No attempts yet	2s	128 MB	Judgeable
Numbers With Equal Remainder and QuotientGiven N, find the sum of all positive integers x whose quotient and remainder are equal when divided by N.	Easy2	Math	No attempts yet	2s	256 MB	Judgeable
Octopus NumbersConvert base-8 strings using nine special symbols (including one for digit -1) into their decimal integer values until a terminator line appears.	Easy2	StringMath+1	No attempts yet	1s	128 MB	Judgeable
Good License PlatesFor each license plate, compute a base-26 value from the three letters and compare it to the four-digit number, printing whether their difference is within 100.	Easy2	StringImplementation+1	No attempts yet	1s	128 MB	Judgeable
Fourth PointGiven two adjacent sides of a parallelogram as endpoint coordinates, compute and print the fourth vertex for each line of input.	Easy2	GeometryMath+1	No attempts yet	2s	128 MB	Judgeable
Making AnagramsGiven two lowercase words, compute how many letters must be deleted in total so their remaining letters match as multisets (anagrams).	Easy2	Hash mapString	No attempts yet	2s	128 MB	Judgeable
Year 2007Given a month and day in 2007, compute and print the corresponding day of the week starting from Monday, Jan 1.	Easy2	MathImplementation	No attempts yet	2s	128 MB	Judgeable
Least Common MultipleFor each of up to 1000 pairs of numbers, compute and print the least common multiple.	Easy2	MathNumber theory	No attempts yet	1s	128 MB	Judgeable
Counting Pentagon PointsCompute the total pentagonal points after N steps using a simple arithmetic formula, modulo 45678.	Easy2	MathImplementation	No attempts yet	2s	256 MB	Judgeable
Perfect SquaresGiven two numbers M and N up to 10000, sum all perfect squares in that inclusive range and print the smallest one, or -1 if none exist.	Easy2	MathBrute force+1	No attempts yet	2s	128 MB	Judgeable
Counting PrimesCount how many of up to 100 given numbers (each at most 1000) are prime.	Easy2	MathBrute force	No attempts yet	2s	128 MB	Judgeable