Problems

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Total results21,088 problems

Provinces and GoldEasy1
ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
AutocompleteEasy1
ImplementationNo attempts yetTime limit2sMemory limit1024 MB
Judgeable
Print HanbyeolEasy1
ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Problem NameEasy1
ImplementationNo attempts yetTime limit2sMemory limit1024 MB
Judgeable
Problem NameEasy1
ImplementationNo attempts yetTime limit2sMemory limit1024 MB
Judgeable
Canadians, eh?Easy1
String, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
SciComLove (2022)Easy1
String, MathNo attempts yetTime limit1sMemory limit256 MB
Judgeable
finitefuncEasy1
Hash mapNo attempts yetTime limit2sMemory limit1024 MB
Judgeable
SproutEasy1
ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
99 ProblemsEasy1
Math, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Culture shockEasy1
String, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
TerraformingEasy1
Implementation, StringNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
ReceiptEasy1
ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Which problem number is the easiest in UCPC?Easy1
ImplementationNo attempts yetTime limit0.5sMemory limit1024 MB
Judgeable
Seongtaek's Secret PasswordEasy1
String, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
TriathlonEasy1
ImplementationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
MBTIEasy1
Implementation, StringNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Calculating defense ignoreEasy1
Implementation, MathNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Easy-to-Solve ExpressionsEasy1
Implementation, MathNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Soccer Standing TableEasy1
ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Nice RaisesEasy1
ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Heavy NumbersEasy1
Implementation, MathNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Corona Virus TestingEasy1
Implementation, MathNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Microwave MishapEasy1
Implementation, MathNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Sharing BirthdaysEasy1
Hash map, StringNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Briefcases Full of MoneyEasy1
ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Window on the WallEasy1
Math, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Electric BillEasy1
Implementation, MathNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Majestic 10Easy1
ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Medal RankingEasy1
ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Lowercase Specific Uppercase LettersEasy1
String, Hash mapNo attempts yetTime limit0.1sMemory limit512 MB
Judgeable
My GrandfatherEasy1
ImplementationNo attempts yetTime limit2sMemory limit1024 MB
Judgeable
WARBOYEasy1
MathNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Cup CoveringEasy1
MathNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
ChronogramEasy1
Implementation, StringNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Intercepting InformationEasy1
ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
PictureEasy1
ImplementationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Command PromptEasy2
String, ImplementationNo attempts yetTime limit2sMemory limit128 MB
Judgeable
Hansu NumbersEasy2
Implementation, Brute force +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
Make It DivisibleEasy2
Brute force, Math +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
White SquaresEasy2
Array, Implementation +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
Word CountEasy2
String, ImplementationNo attempts yetTime limit2sMemory limit128 MB
Judgeable
Most Frequent LetterEasy2
Hash map, String +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
Basketball GameEasy2
Hash map, Implementation +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Word SortingEasy2
Sorting, StringNo attempts yetTime limit2sMemory limit256 MB
Judgeable
Octal to BinaryEasy2
String, Implementation +1No attempts yetTime limit1sMemory limit256 MB
Judgeable
Sign of Integer SumsEasy2
Implementation, MathNo attempts yetTime limit2sMemory limit256 MB
Judgeable
Splitting a WordEasy2
String, Brute force +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
Mobile Phone BillEasy2
Simulation, Implementation +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
House Number SignEasy2
Implementation, String +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Easy Sequence SumEasy2
Math, Simulation +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
Choosing a Team NameEasy2
String, Implementation +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
TV SizeEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit128 MB
Judgeable
Group Word CheckerEasy2
String, ImplementationNo attempts yetTime limit2sMemory limit128 MB
Judgeable
Year Progress BarEasy2
Implementation, MathNo attempts yetTime limit2sMemory limit128 MB
Judgeable
Actual Disk SpaceEasy2
Math, Implementation +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
Yujin NumberEasy2
String, Brute force +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
Reversed AdditionEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit128 MB
Judgeable
PetEasy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Most Frequent LettersEasy2
Hash map, String +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
EarringsEasy2
Hash map, Array +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Floor DecorationEasy2
Matrix, Implementation +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
Song ScoresEasy2
Prefix sum, Binary search +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
24-Hour MissionEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit128 MB
Judgeable
Sort Digits DescendingEasy2
Sorting, String +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
Organizing BooksEasy2
Simulation, Implementation +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
Time MachineEasy2
Combinatorics, Brute force +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
Internet Cafe Seat RequestsEasy2
Simulation, Array +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
Room NumberEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit128 MB
Judgeable
Adjusted AverageEasy2
Array, Math +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
BallEasy2
Simulation, ImplementationNo attempts yetTime limit2sMemory limit128 MB
Judgeable
Sequence TransformationEasy2
Array, Simulation +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
Manhattan Distance on a Four-Row Number BoardEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit128 MB
Judgeable
Find Places to Lie DownEasy2
Matrix, SimulationNo attempts yetTime limit2sMemory limit128 MB
Judgeable
Trophy DisplayEasy2
Array, ImplementationNo attempts yetTime limit2sMemory limit128 MB
Judgeable
Chicken CouponsEasy2
Math, Simulation +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
Growth PointsEasy2
Simulation, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Break-Even PointEasy2
Math, ImplementationNo attempts yetTime limit0.35sMemory limit128 MB
Judgeable
Next Term in a SequenceEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit128 MB
Judgeable
Fraction SumEasy2
Math, Number theory +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
Concatenating Numbers 1Easy2
Math, ImplementationNo attempts yetTime limit0.15sMemory limit128 MB
Judgeable
Packing Books into BoxesEasy2
Greedy, Array +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
Numbers With Equal Remainder and QuotientEasy2
MathNo attempts yetTime limit2sMemory limit256 MB
Judgeable
Octopus NumbersEasy2
String, Math +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Good License PlatesEasy2
String, Implementation +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Fourth PointEasy2
Geometry, Math +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
Making AnagramsEasy2
Hash map, StringNo attempts yetTime limit2sMemory limit128 MB
Judgeable
Year 2007Easy2
Math, ImplementationNo attempts yetTime limit2sMemory limit128 MB
Judgeable
Least Common MultipleEasy2
Math, Number theoryNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Counting Pentagon PointsEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit256 MB
Judgeable
Perfect SquaresEasy2
Math, Brute force +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
Counting PrimesEasy2
Math, Brute forceNo attempts yetTime limit2sMemory limit128 MB
Judgeable
PlugsEasy2
Math, Greedy +1No attempts yetTime limit2sMemory limit256 MB
Judgeable
Self-Replicating NumberEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit128 MB
Judgeable
Day of the YearEasy2
Implementation, MathNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Number GameEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit128 MB
Judgeable
Prime WordEasy2
String, Math +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
Dobby's Case-Insensitive Word TestEasy2
String, Sorting +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Restoring NumbersEasy2
Math, Number theory +1No attempts yetTime limit2sMemory limit128 MB
Judgeable
Sum of Consecutive IntegersEasy2
Math, ImplementationNo attempts yetTime limit0.25sMemory limit128 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Provinces and GoldGiven the counts of Gold, Silver, and Copper in a hand, find the best victory card and best treasure card Jake can afford with his total buying power.	Easy1	Implementation	No attempts yet	1s	1024 MB	Judgeable
AutocompleteReads one letter and prints Naver D2 if it is N or n, otherwise prints Naver Whale.	Easy1	Implementation	No attempts yet	2s	1024 MB	Judgeable
Print HanbyeolThe task is to print the word Hanbyeol to standard output.	Easy1	Implementation	No attempts yet	1s	1024 MB	Judgeable
Problem NameThe statement is withheld, so the only instruction is to write an internet letter from the listed birth date, enlistment date, and name.	Easy1	Implementation	No attempts yet	2s	1024 MB	Judgeable
Problem NameA joke problem with no input that asks for a list of words taken from a letter, with no statement given.	Easy1	Implementation	No attempts yet	2s	1024 MB	Judgeable
Canadians, eh?Given one line of text, decide whether it ends with the exact string eh? and print Canadian! or Imposter!.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
SciComLove (2022)Given N up to 10^9, print the string SciComLove after moving its first character to the end N times.	Easy1	StringMath	No attempts yet	1s	256 MB	Judgeable
finitefuncGiven a dictionary D, return the set of its values as a Python set.	Easy1	Hash map	No attempts yet	2s	1024 MB	Judgeable
SproutPrint a fixed sprout drawing exactly as shown in the example. The program takes no input and only writes the picture to standard output.	Easy1	Implementation	No attempts yet	1s	1024 MB	Judgeable
99 ProblemsGiven a price N, find the positive integer closest to N that ends in 99, breaking ties toward the larger value.	Easy1	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Culture shockCount how many words in a sentence are he, him, she, or her, given N words on one line.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
TerraformingAdds up Mars oxygen, ocean, and temperature changes from a list and checks whether oxygen reaches 14%, oceans reach 9%, and temperature reaches +8 C.	Easy1	ImplementationString	No attempts yet	1s	1024 MB	Judgeable
ReceiptGiven a printed receipt total and each item's price and quantity, check whether the sum of price times quantity equals the total.	Easy1	Implementation	No attempts yet	1s	1024 MB	Judgeable
Which problem number is the easiest in UCPC?Given a UCPC preliminary contest year from 2018 to 2022, print the letter of the easiest problem the setters intended that year.	Easy1	Implementation	No attempts yet	0.5s	1024 MB	Judgeable
Seongtaek's Secret PasswordGiven N strings, the task is to print yes for each string whose length is between 6 and 9 characters, otherwise no.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
TriathlonGiven N participants' scores a, d, and g, compute a times (d+g), doubled when a equals d+g, and print the highest score.	Easy1	Implementation	No attempts yet	1s	512 MB	Judgeable
MBTIGiven Jinho's MBTI type and N friends' types, count how many friends share Jinho's type.	Easy1	ImplementationString	No attempts yet	1s	512 MB	Judgeable
Calculating defense ignoreGiven N potions with percent defense ignore values, print the combined defense ignore after each drink using 1 - (1 - V)(1 - A_i).	Easy1	ImplementationMath	No attempts yet	1s	512 MB	Judgeable
Easy-to-Solve ExpressionsGiven three distinct integers, the task is to check whether one is the sum or the product of the other two, printing 1, 2, or 3.	Easy1	ImplementationMath	No attempts yet	1s	1024 MB	Judgeable
Soccer Standing TableGiven five integers from a soccer standings row, print them in the order matches, wins, draws, losses, points.	Easy1	Implementation	No attempts yet	1s	1024 MB	Judgeable
Nice RaisesGiven a fixed raise and n salaries, count whether more members prefer the fixed raise or doubling their salary, printing 1, 2, or 0 on a tie.	Easy1	Implementation	No attempts yet	1s	1024 MB	Judgeable
Heavy NumbersGiven two integers up to 1,000,000, compute each number's digit count times its digit sum, then print 1 or 2 for the heavier one, or 0 on a tie.	Easy1	ImplementationMath	No attempts yet	1s	1024 MB	Judgeable
Corona Virus TestingGiven g groups of p people and t positive groups, the task compares individual testing with group testing and prints which uses fewer kits.	Easy1	ImplementationMath	No attempts yet	1s	1024 MB	Judgeable
Microwave MishapGiven an MM:SS entry that the microwave reads as HH:MM, print the extra cooking time as HH:MM:SS.	Easy1	ImplementationMath	No attempts yet	1s	1024 MB	Judgeable
Sharing BirthdaysGiven n birthdays written as mm/dd, count how many distinct dates appear, with duplicates counted once.	Easy1	Hash mapString	No attempts yet	1s	1024 MB	Judgeable
Briefcases Full of MoneyGiven the bill counts for six denominations, print the denomination of the briefcase with the largest total, breaking ties by choosing the one with fewest bills.	Easy1	Implementation	No attempts yet	1s	1024 MB	Judgeable
Window on the WallGiven a wall's width, height, and border gap, find the area of the largest window that keeps the gap on every side.	Easy1	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Electric BillGiven two per-KWH rates and customer consumptions, the task prints each customer's bill, with the first 1000 KWH at the lower rate.	Easy1	ImplementationMath	No attempts yet	1s	1024 MB	Judgeable
Majestic 10For each player's three stats, count how many are at least 10 and print the matching label (zilch, double, double-double, or triple-double).	Easy1	Implementation	No attempts yet	1s	1024 MB	Judgeable
Medal RankingFor each test case, read USA and Russia's gold, silver, and bronze counts and report whether USA wins by total medal count, by color order, both, or neither.	Easy1	Implementation	No attempts yet	1s	1024 MB	Judgeable
Lowercase Specific Uppercase LettersGiven a string A and a list B of uppercase letters, lowercase every occurrence of each letter in B within A and print the result.	Easy1	StringHash map	No attempts yet	0.1s	512 MB	Judgeable
My GrandfatherThe statement holds only a title and the placeholder word "Stattopic", so the task it asks for cannot be determined.	Easy1	Implementation	No attempts yet	2s	1024 MB	Judgeable
WARBOYGiven the competitor's price A, the competitor's performance B, and WARBOY's price C, find WARBOY's performance when its price-to-performance is 3 times the competitor's.	Easy1	Math	No attempts yet	1s	1024 MB	Judgeable
Cup CoveringGiven the area of a circle, output its diameter with an absolute or relative error of at most 1e-9.	Easy1	Math	No attempts yet	1s	1024 MB	Judgeable
ChronogramGiven text lines, sum the Roman numeral letter values (I, V, X, L, C, D, M) in each line and output the total as the year.	Easy1	ImplementationString	No attempts yet	1s	1024 MB	Judgeable
Intercepting InformationGiven 8 readings that are each 0, 1, or 9, the task prints S if no reading is 9 and F otherwise.	Easy1	Implementation	No attempts yet	1s	1024 MB	Judgeable
PictureThe task asks the solver to print a picture from the original contest, but the picture itself is missing from this statement.	Easy1	Implementation	No attempts yet	1s	512 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
PlugsGiven N power strips each with a plug capacity, compute the max number of computers powered when strips are chained from one wall outlet.	Easy2	MathGreedy+1	No attempts yet	2s	256 MB	Judgeable
Self-Replicating NumberCheck whether squaring an integer N reproduces N as the trailing digits of N squared.	Easy2	MathImplementation	No attempts yet	2s	128 MB	Judgeable
Day of the YearGiven day, month, year, compute the day's ordinal number within that year accounting for leap years, until a 0 0 0 terminator.	Easy2	ImplementationMath	No attempts yet	1s	128 MB	Judgeable
Number GameRepeatedly sum decimal digits of each number until one digit remains, processing lines until a terminating zero.	Easy2	MathImplementation	No attempts yet	2s	128 MB	Judgeable
Prime WordSum letter values (a-z=1-26, A-Z=27-52) for a word and print whether the sum is prime (with 1 counted as prime).	Easy2	StringMath+1	No attempts yet	2s	128 MB	Judgeable
Dobby's Case-Insensitive Word TestFor each test case, output the original-cased word that is smallest in dictionary order when comparisons ignore letter case.	Easy2	StringSorting+1	No attempts yet	1s	128 MB	Judgeable
Restoring NumbersFor each given integer up to 100,000, output its prime factorization as prime-exponent pairs in increasing order.	Easy2	MathNumber theory+1	No attempts yet	2s	128 MB	Judgeable
Sum of Consecutive IntegersGiven two integers, print the sum of all integers in the closed range between them, handling either order.	Easy2	MathImplementation	No attempts yet	0.25s	128 MB	Judgeable