Problems

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Total results21,518 problems

Algorithm Class - Algorithm Runtime 6Easy2
Math, Combinatorics +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Numbers Between CharactersEasy2
String, Implementation +1No attempts yetTime limit2sMemory limit1024 MB
Judgeable
ПЪТУВАНЕEasy2
Math, Implementation +2No attempts yetTime limit1sMemory limit1024 MB
Judgeable
Algorithm Class - Asymptotic Notation 1Easy2
Math, Implementation +2No attempts yetTime limit1sMemory limit512 MB
Judgeable
Making ChangeEasy2
Greedy, Math +2No attempts yetTime limit1sMemory limit1024 MB
Judgeable
Meeting of FriendsEasy2
Math, Intervals +1No attempts yetTime limit0.1sMemory limit1024 MB
Judgeable
ClockEasy2
Math, Implementation +2No attempts yetTime limit1sMemory limit1024 MB
Judgeable
MinesweeperEasy2
Implementation, Array +2No attempts yetTime limit1sMemory limit1024 MB
Judgeable
Zayo BayoEasy2
Simulation, Implementation +2No attempts yetTime limit1sMemory limit1024 MB
Judgeable
Algorithm Class - Asymptotic Notation 4Easy2
Math, Implementation +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Algorithm Class - Asymptotic Notation 5Easy2
Math, Implementation +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Algorithm Class - Asymptotic Notation 6Easy2
Math, Implementation +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Three MatchesEasy2
Implementation, Sorting +2No attempts yetTime limit1sMemory limit1024 MB
Judgeable
Eye of SauronEasy2
String, Implementation +1No attempts yetTime limit1sMemory limit1024 MB
Judgeable
Algorithm Class - Fibonacci Number 1Easy2
Implementation, Math +2No attempts yetTime limit1sMemory limit512 MB
Judgeable
Piano CompetitionEasy2
Array, Implementation +1No attempts yetTime limit2sMemory limit1024 MB
Judgeable
Library 2Easy2
Stack, Simulation +1No attempts yetTime limit2sMemory limit1024 MB
Judgeable
Dodo Learns Time ComplexityEasy2
String, Implementation +1No attempts yetTime limit1sMemory limit1024 MB
Judgeable
Fergusonball RatingsEasy2
Implementation, Math +1No attempts yetTime limit1sMemory limit1024 MB
Judgeable
Harp TuningEasy2
String, Implementation +1No attempts yetTime limit1sMemory limit1024 MB
Judgeable
Espresso!Easy2
Simulation, Implementation +1No attempts yetTime limit1sMemory limit1024 MB
Judgeable
Ultimate Binary WatchEasy2
Bit manipulation, Implementation +2No attempts yetTime limit1sMemory limit1024 MB
Judgeable
Scaling RecipeEasy2
Math, Implementation +1No attempts yetTime limit1sMemory limit1024 MB
Judgeable
Double PasswordEasy2
Math, Combinatorics +2No attempts yetTime limit1sMemory limit1024 MB
Judgeable
Average CharacterEasy2
String, Math +1No attempts yetTime limit1sMemory limit1024 MB
Judgeable
BlocksEasy2
Backtracking, Brute force +2No attempts yetTime limit1sMemory limit1024 MB
Judgeable
Green TowerEasy2
Brute force, ImplementationNo attempts yetTime limit2.022sMemory limit319 MB
Judgeable
Pooling PCR TestsEasy2
Math, Brute forceNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Transporting SpaghettiEasy2
Math, Brute forceNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
BettingEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
MiaEasy2
ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
BeehivesEasy2
Brute force, MathNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Carousel RidesEasy2
Implementation, Brute forceNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
The Amazing Human CannonballEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Kitten on a TreeEasy2
Tree, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Number FunEasy2
Implementation, MathNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Turtle MasterEasy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Saving Princess PeachEasy2
Array, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Climbing WormEasy2
Math, SimulationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Math HomeworkEasy2
Brute force, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Broken SwordsEasy2
Implementation, GreedyNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Good MessagesEasy2
String, SimulationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Broken CalculatorEasy2
ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Two RabbitsEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Friendly RooksEasy2
Implementation, GreedyNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Counting AntibodiesEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Calendar of Alpha CentauriEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Binary Game 2Easy2
Implementation, MathNo attempts yetTime limit1sMemory limit512 MB
Judgeable
PatchworkEasy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Trip OdometerEasy2
Array, SortingNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Time and DateEasy2
ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
August14 Beginner ContestEasy2
Implementation, Hash mapNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Organizing SWERCEasy2
Array, ImplementationNo attempts yetTime limit2sMemory limit2048 MB
Judgeable
Punched CardsEasy2
Implementation, StringNo attempts yetTime limit5sMemory limit1024 MB
Judgeable
KHLEasy2
Implementation, StringNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
TiMEasy2
String, ImplementationNo attempts yetTime limit2sMemory limit1024 MB
Judgeable
Ari's Clever Portal TripEasy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
두~~부 두부 두부Easy2
Math, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Searching for Sogang's HistoryEasy2
Implementation, ArrayNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
One Shot at LifeEasy2
String, SimulationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Cake slicesEasy2
Brute force, MathNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Gahee and Ignoring Defense RateEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Military Service ExaminationEasy2
ImplementationNo attempts yetTime limit2sMemory limit1024 MB
Judgeable
November 11Easy2
Implementation, SimulationNo attempts yetTime limit2sMemory limit1024 MB
Judgeable
CutlineEasy2
Sorting, ArrayNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Coding Is a Physical Education SubjectEasy2
String, ImplementationNo attempts yetTime limit0.5sMemory limit1024 MB
Judgeable
Measuring Student PopularityEasy2
Hash map, Sorting +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Multi-Field Preference Survey (Small)Easy2
Implementation, Brute forceNo attempts yetTime limit1sMemory limit512 MB
Judgeable
A Very Simple ProblemEasy2
Math, Number theoryNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
BreadEasy2
Implementation, Brute forceNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Simple Problem (Small)Easy2
Brute force, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
AirPodsEasy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Linked Master ImsEasy2
String, SimulationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Counting Peaks of InfectionEasy2
Array, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
NavigationEasy2
Implementation, ArrayNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Puang and JongyunEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Shuttle BusEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit1024 MB
Judgeable
Making HamburgersEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Odd-Even SequenceEasy2
Sorting, ImplementationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Palindrome Sotteok-SotteokEasy2
String, Two pointersNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Attendance EventEasy2
Implementation, MathNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Computation - Task 1Easy2
Implementation, MathNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Computation - Task 5Easy2
Bit manipulation, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Mirror ReflectionEasy2
Matrix, ImplementationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Minigames with ImsEasy2
Hash map, MathNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Number MaximizationEasy2
Sorting, StringNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Easy-to-Pronounce WordsEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Decimal XOREasy2
Implementation, MathNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Changing StringsEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Cat's AgeEasy2
Implementation, MathNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Presidential ElectionEasy2
ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Digit CountEasy2
Implementation, Brute forceNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Judging Assistant for ContestEasy2
Implementation, StringNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
A Game Called MindEasy2
Sorting, ArrayNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Parity of StringsEasy2
Array, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Simplified KeyboardEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Hi Cleopatra, the Best Potato Chip in the WorldEasy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Polar Bear Tears BracketsEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Find the TwinsEasy2
Implementation, ArrayNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Brownies vs. Candies vs. CookiesEasy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Algorithm Class - Algorithm Runtime 6Count how many times the triple nested loop runs for a given n, then report the polynomial degree of that count.	Easy2	MathCombinatorics+1	No attempts yet	1s	512 MB	Judgeable
Numbers Between CharactersRead an integer N and a four-character string, then print N times each digit found, or N/A if there are no digits.	Easy2	StringImplementation+1	No attempts yet	2s	1024 MB	Judgeable
ПЪТУВАНЕGiven a conference start time and fixed activity durations, compute the latest departure time so the group arrives at least 10 minutes early.	Easy2	MathImplementation+2	No attempts yet	1s	1024 MB	Judgeable
Algorithm Class - Asymptotic Notation 1Given f(n) = a1n + a0 and constants c and n0, decide whether f(n) <= cn holds for every n >= n0.	Easy2	MathImplementation+2	No attempts yet	1s	512 MB	Judgeable
Making ChangeFor each pair of cost and payment amounts, compute the change and break it into the fewest $50, $20, $10, $5, and $1 bills.	Easy2	GreedyMath+2	No attempts yet	1s	1024 MB	Judgeable
Meeting of FriendsGiven two available time intervals and one minute when the second friend is busy, count the minutes both are free at the same time.	Easy2	MathIntervals+1	No attempts yet	0.1s	1024 MB	Judgeable
ClockGiven a start time and an end time on a 24-hour clock, compute the elapsed minutes (less than a day) and the number of full 30-minute laps.	Easy2	MathImplementation+2	No attempts yet	1s	1024 MB	Judgeable
MinesweeperGiven a 3x3 grid marking bombs with 9, replace each non-bomb cell with the count of bombs in its up to eight neighboring cells.	Easy2	ImplementationArray+2	No attempts yet	1s	1024 MB	Judgeable
Zayo BayoGiven x cabbages, a travel time of n days per trip, and a start date, find the date when the last cabbage reaches home.	Easy2	SimulationImplementation+2	No attempts yet	1s	1024 MB	Judgeable
Algorithm Class - Asymptotic Notation 4Given a quadratic f(n) and constants c, n0, decide whether f(n) <= c*n^2 holds for every n >= n0.	Easy2	MathImplementation+1	No attempts yet	1s	512 MB	Judgeable
Algorithm Class - Asymptotic Notation 5Given a quadratic f(n) and positive c, n0, decide whether c*n^2 <= f(n) holds for every n >= n0, printing 1 or 0.	Easy2	MathImplementation+1	No attempts yet	1s	512 MB	Judgeable
Algorithm Class - Asymptotic Notation 6Given a quadratic f(n)=a2n^2+a1n+a0 and constants c1, c2, n0, decide whether c1n^2 <= f(n) <= c2n^2 holds for every n >= n0.	Easy2	MathImplementation+1	No attempts yet	1s	512 MB	Judgeable
Three MatchesGiven three matches on a line, find the minimum number to light so fire spreads to all, and report the shortest and longest lengths.	Easy2	ImplementationSorting+2	No attempts yet	1s	1024 MB	Judgeable
Eye of SauronGiven a string of bars surrounding a single matched pair of parentheses, decide whether the bar counts on the left and right sides are equal.	Easy2	StringImplementation+1	No attempts yet	1s	1024 MB	Judgeable
Algorithm Class - Fibonacci Number 1Given n, count how many times the base case of naive recursive Fibonacci runs and how many times the DP loop body runs.	Easy2	ImplementationMath+2	No attempts yet	1s	512 MB	Judgeable
Piano CompetitionGiven N distinct judge scores, output the sum of all scores except the highest and the lowest.	Easy2	ArrayImplementation+1	No attempts yet	2s	1024 MB	Judgeable
Library 2Process a sequence of push and pop actions on a stack of book titles, printing the title each time a READ pop occurs.	Easy2	StackSimulation+1	No attempts yet	2s	1024 MB	Judgeable
Dodo Learns Time ComplexityGiven lines of lowercase text, count how many times the substrings "for" and "while" appear on each line and print the largest count.	Easy2	StringImplementation+1	No attempts yet	1s	1024 MB	Judgeable
Fergusonball RatingsFor each player, compute 5 times points minus 3 times fouls, count how many exceed 40, and mark the team gold if all do.	Easy2	ImplementationMath+1	No attempts yet	1s	1024 MB	Judgeable
Harp TuningSplit one line of concatenated harp tuning instructions into separate lines showing the strings, tighten or loosen, and the turn count.	Easy2	StringImplementation+1	No attempts yet	1s	1024 MB	Judgeable
Espresso!Given orders of 1 to 4 shots (latte adds one ounce) and a tank of s ounces, count refills needed to serve all orders in order.	Easy2	SimulationImplementation+1	No attempts yet	1s	1024 MB	Judgeable
Ultimate Binary WatchGiven a 24-hour time as four digits, print a four-column binary LED watch face with asterisks for set bits and periods for clear bits.	Easy2	Bit manipulationImplementation+2	No attempts yet	1s	1024 MB	Judgeable
Scaling RecipeScale each ingredient amount from a recipe that makes x portions so it makes y portions instead.	Easy2	MathImplementation+1	No attempts yet	1s	1024 MB	Judgeable
Double PasswordGiven two four-digit passwords, count how many four-digit sequences match at least one password in every digit position.	Easy2	MathCombinatorics+2	No attempts yet	1s	1024 MB	Judgeable
Average CharacterGiven a printable ASCII string, output the character whose ASCII value is the floor of the average of all characters' ASCII values.	Easy2	StringMath+1	No attempts yet	1s	1024 MB	Judgeable
BlocksGiven four blocks with six letters each, decide for each short word whether its letters can be assigned to distinct blocks that contain them.	Easy2	BacktrackingBrute force+2	No attempts yet	1s	1024 MB	Judgeable
Green TowerCount the shortest downward paths from the top of an N-floor Green Tower to the yellow floor, moving one adjacent floor at a time over visible blocks.	Easy2	Brute forceImplementation	No attempts yet	2.022s	319 MB	Judgeable
Pooling PCR TestsGiven the chance p that one person tests positive, find the pool size N (2 to 16) that minimizes expected PCR tests per person, or print 1.	Easy2	MathBrute force	No attempts yet	1s	1024 MB	Judgeable
Transporting SpaghettiFind the fewest full trucks from Milan so that Mestre keeps exactly D tons and the rest, shipped in full boats, is at least C tons for Venice.	Easy2	MathBrute force	No attempts yet	1s	1024 MB	Judgeable
BettingGiven the percentage a of switch points bet on option one, print the payout ratio x for each option, where the ratio is 1:x.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
MiaGiven two dice rolls for each player, decide who wins under Mia scoring: Mia is highest, then doubles, then the larger digit first.	Easy2	Implementation	No attempts yet	1s	1024 MB	Judgeable
BeehivesGiven hive coordinates and a distance d, count the hives within d of another hive (sour) and the hives with no such neighbor (sweet).	Easy2	Brute forceMath	No attempts yet	1s	1024 MB	Judgeable
Carousel RidesFor each test case, pick the offer with the lowest price per ticket among those buying at most m tickets, breaking ties toward the offer that buys more tickets.	Easy2	ImplementationBrute force	No attempts yet	1s	1024 MB	Judgeable
The Amazing Human CannonballFor each test case, the task checks whether the cannonball's height where it crosses the wall is at least 1 m above the lower edge and at least 1 m below the upper edge.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Kitten on a TreeGiven a tree as parent lines with their child branches and the kitten's branch K, print the path from K up to the root.	Easy2	TreeImplementation	No attempts yet	1s	1024 MB	Judgeable
Number FunGiven triples a, b, c, the task is to check whether c equals a+b, a-b, b-a, a*b, a/b, or b/a for one operation, printing Possible or Impossible.	Easy2	ImplementationMath	No attempts yet	1s	1024 MB	Judgeable
Turtle MasterSimulate a turtle program on an 8 by 8 board with F, R, L, X moves and report whether it reaches the diamond without errors.	Easy2	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable
Saving Princess PeachGiven N obstacles and Mario's list of finds with repeats, print the numbers he missed in increasing order, then the count of distinct obstacles he found.	Easy2	ArrayImplementation	No attempts yet	1s	1024 MB	Judgeable
Climbing WormGiven a climb a, a slide b, and a pole height h, the task is to count how many crawls the worm needs to reach the top.	Easy2	MathSimulation	No attempts yet	1s	1024 MB	Judgeable
Math HomeworkGiven the leg counts b, d, c of three animal types and a total of l legs, list every count triple whose legs add up to l, or print impossible.	Easy2	Brute forceImplementation	No attempts yet	1s	1024 MB	Judgeable
Broken SwordsGiven which slats of each broken sword are broken, count how many swords Ken can rebuild and how many T/B and L/R slats remain.	Easy2	ImplementationGreedy	No attempts yet	1s	1024 MB	Judgeable
Good MessagesApplies a Caesar shift to a message up to N times and counts steps where vowels (including y) are at least half the consonants, printing Boris or Colleague.	Easy2	StringSimulation	No attempts yet	1s	1024 MB	Judgeable
Broken CalculatorSimulate a broken calculator whose four operators each use the previous result, and print the displayed value after each command.	Easy2	Implementation	No attempts yet	1s	1024 MB	Judgeable
Two RabbitsTwo rabbits hop toward each other by fixed distances each second; find the time they land on the same point, or -1 if they never do.	Easy2	MathImplementation	No attempts yet	1s	256 MB	Judgeable
Friendly RooksPlace k rooks on an n by m board so that no two rooks share a row or column, or report Impossible when that cannot be done.	Easy2	ImplementationGreedy	No attempts yet	1s	512 MB	Judgeable
Counting AntibodiesGiven the gene fragment counts for the kappa, lambda, and heavy chains, count how many distinct antibody molecules can be formed.	Easy2	MathImplementation	No attempts yet	1s	512 MB	Judgeable
Calendar of Alpha CentauriGiven a calendar with m months of d days each and a w-day week labeled a to the w-th letter, find the weekday letter for day i of month j in year k.	Easy2	MathImplementation	No attempts yet	1s	512 MB	Judgeable
Binary Game 2Given n, print the binary digits of every number from 0 to n in order, concatenated into one digit sequence.	Easy2	ImplementationMath	No attempts yet	1s	512 MB	Judgeable
PatchworkGiven an R by C quilt and a sequence of patch placements, print the final grid after each patch is stamped on and clipped at the edges.	Easy2	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable
Trip OdometerGiven N trip distances, find every distinct total that remains after removing exactly one distance from the list, sorted in ascending order.	Easy2	ArraySorting	No attempts yet	1s	1024 MB	Judgeable
Time and DateGiven x and y, check whether they form a valid 24-hour time (x hours y minutes) and a valid month and day date (x month y day).	Easy2	Implementation	No attempts yet	1s	1024 MB	Judgeable
August14 Beginner ContestGiven N problem IDs, print E, H, or VH for each one based on whether the user solved, attempted, or never touched it. Input and output handling is the main work.	Easy2	ImplementationHash map	No attempts yet	1s	1024 MB	Judgeable
Organizing SWERCFor each test, take the most beautiful problem at each difficulty 1 to 10 and sum the beauty, or print MOREPROBLEMS if one is missing.	Easy2	ArrayImplementation	No attempts yet	2s	2048 MB	Judgeable
Punched CardsGiven R and C, print an ASCII punched card with R rows and C columns, where each cell is a period inside a border of dashes, pipes, and plus signs.	Easy2	ImplementationString	No attempts yet	5s	1024 MB	Judgeable
KHLGiven N game results with period, overtime, and shootout scores, compute the total points Medveščak earns across all games.	Easy2	ImplementationString	No attempts yet	1s	1024 MB	Judgeable
TiMGiven the characters of an alternating X or number and +/- expression, output the digit sum, the sum of the numbers, and the X value that makes it zero.	Easy2	StringImplementation	No attempts yet	2s	1024 MB	Judgeable
Ari's Clever Portal TripSimulate Ari's zigzag walk from row 1 to the portal at (N, M) and report whether the path passes through the minion cell (Sr, Sc).	Easy2	SimulationImplementation	No attempts yet	1s	512 MB	Judgeable
두~~부 두부 두부Given N players in a circle, caller M, and called mo count K, output the number of the player whose mo count is K, who takes the next turn.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Searching for Sogang's HistoryGiven current and freshman-era facility scores for campus places, find the largest increase in total score from restoring at most one place.	Easy2	ImplementationArray	No attempts yet	1s	1024 MB	Judgeable
One Shot at LifeDecide whether a string of uppercase letters has a run of 5 or more characters where each adjacent pair is alphabetically consecutive.	Easy2	StringSimulation	No attempts yet	1s	1024 MB	Judgeable
Cake slicesGiven up to 10 cake slices, where slice i is 1/c_i of a cake, count the subsets whose total size is between 99/100 and 101/100 of a cake.	Easy2	Brute forceMath	No attempts yet	1s	1024 MB	Judgeable
Gahee and Ignoring Defense RateGiven a monster's defense rate a and the user's ignore defense b (in percent), print 1 if the remaining defense rate is under 100, otherwise print 0.	Easy2	MathImplementation	No attempts yet	1s	512 MB	Judgeable
Military Service ExaminationGiven each person's height and weight, print the military service grade (1 to 6) from a table that uses height ranges and BMI.	Easy2	Implementation	No attempts yet	2s	1024 MB	Judgeable
November 11For each year and month, find the date that is m days before month m, day m of that year, using the calendar with leap-year rules.	Easy2	ImplementationSimulation	No attempts yet	2s	1024 MB	Judgeable
CutlineGiven N student scores, find the k-th highest score, which is the lowest score among the top k students.	Easy2	SortingArray	No attempts yet	1s	1024 MB	Judgeable
Coding Is a Physical Education SubjectGiven N, a multiple of 4, print the C++ integer type name with N/4 copies of "long" followed by "int" that can store up to N bytes.	Easy2	StringImplementation	No attempts yet	0.5s	1024 MB	Judgeable
Measuring Student PopularityGiven n student names and each student's list of liked classmates, count how many students like each name and print the names sorted by count descending, then by name ascending.	Easy2	Hash mapSorting+1	No attempts yet	1s	512 MB	Judgeable
Multi-Field Preference Survey (Small)Given n student preference triples and m queries with wildcards, count the students matching each query's subject, fruit, and color.	Easy2	ImplementationBrute force	No attempts yet	1s	512 MB	Judgeable
A Very Simple ProblemFor each query with positive integers a and b, decide whether positive integers x and y exist with gcd(x, y) = a and x + y = b.	Easy2	MathNumber theory	No attempts yet	1s	1024 MB	Judgeable
BreadGiven each shop's travel time A and the bread's arrival time B, find the earliest time you can buy a loaf, or -1 if no shop works.	Easy2	ImplementationBrute force	No attempts yet	1s	1024 MB	Judgeable
Simple Problem (Small)Count tuples (x, y, z) within the bounds 1 to a, 1 to b, and 1 to c where x mod y, y mod z, and z mod x are all equal.	Easy2	Brute forceImplementation	No attempts yet	1s	1024 MB	Judgeable
AirPodsSimulate the AirPods battery use across N phone connections, doubling the cost on a repeat connection and resetting at 100 percent, then print the current level.	Easy2	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable
Linked Master ImsCount the skills that fire normally, where each R or K pairs with an earlier unused L or S, and an unmatched main skill breaks all later skills.	Easy2	StringSimulation	No attempts yet	1s	1024 MB	Judgeable
Counting Peaks of InfectionCount the peaks in each dataset of daily positive case counts, where a peak is a day with more cases than both the day before and the day after.	Easy2	ArrayImplementation	No attempts yet	1s	1024 MB	Judgeable
NavigationGiven N routes that pass through ordered intermediate points, find the route number with the smallest total Manhattan distance from start to end.	Easy2	ImplementationArray	No attempts yet	1s	1024 MB	Judgeable
Puang and JongyunGiven two two-digit numbers, compute their product with the Vedic method, printing the intermediate values a, b, c, d, q, r and the product's two halves.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Shuttle BusGiven the one-way trip time x and the bus's arrival time y at Engineering Building 2, find the minimum minutes to wait for the bus at the station.	Easy2	MathImplementation	No attempts yet	2s	1024 MB	Judgeable
Making HamburgersGiven A buns and B patties, find the maximum number of hamburgers, where each hamburger uses two buns and one patty.	Easy2	MathImplementation	No attempts yet	1s	512 MB	Judgeable
Odd-Even SequenceDecide whether the sequence can be rearranged so odd positions hold sorted odd values and even positions hold sorted even values.	Easy2	SortingImplementation	No attempts yet	1s	512 MB	Judgeable
Palindrome Sotteok-SotteokGiven a string of 's' and 't', find the minimum number of single-character changes needed to make it a palindrome.	Easy2	StringTwo pointers	No attempts yet	1s	512 MB	Judgeable
Attendance EventGiven stamps collected and an item price, the task is to find the minimum payment using at most one coupon whose tier the stamp count unlocks.	Easy2	ImplementationMath	No attempts yet	1s	1024 MB	Judgeable
Computation - Task 1Given real numbers a and b, write an instruction program that prints -2a-2b using input, addition, negation, and shift operations.	Easy2	ImplementationMath	No attempts yet	1s	1024 MB	Judgeable
Computation - Task 5Read 32 bits a_1 to a_32 (most significant first) and print their value in base 10 using only the given instructions.	Easy2	Bit manipulationImplementation	No attempts yet	1s	1024 MB	Judgeable
Mirror ReflectionGiven an N by N digit grid and a flip direction (L, R, U, or D), print the grid as a mirror would show it, with ? for digits that have no readable flipped form.	Easy2	MatrixImplementation	No attempts yet	1s	512 MB	Judgeable
Minigames with ImsCount the distinct names, then divide by the other players each game needs: 1 for Yut Nori, 2 for Find the Same Picture, 3 for One Card.	Easy2	Hash mapMath	No attempts yet	1s	512 MB	Judgeable
Number MaximizationGiven an integer of up to six digits, rearrange its digits to form the largest number possible.	Easy2	SortingString	No attempts yet	1s	1024 MB	Judgeable
Easy-to-Pronounce WordsGiven a lowercase word, print 1 if its vowels and consonants strictly alternate, and 0 otherwise.	Easy2	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Decimal XORGiven two integers up to 999,999, compute their digit-wise DEXOR, where each digit pair gives 0 if both digits are at most 2 or both are at least 7, otherwise 9.	Easy2	ImplementationMath	No attempts yet	1s	1024 MB	Judgeable
Changing StringsGiven an uppercase string, replace characters outside the leftmost U to rightmost F span with hyphens and those inside with C.	Easy2	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Cat's AgeGiven a cat's age in years and months, convert it to human age in years and months using the 15, 9, and 4 rule.	Easy2	ImplementationMath	No attempts yet	1s	1024 MB	Judgeable
Presidential ElectionGiven each state's electoral votes and both candidates' vote counts, decide who wins the popular vote and who wins the electoral vote.	Easy2	Implementation	No attempts yet	1s	1024 MB	Judgeable
Digit CountGiven a range of 4-digit integers and a digit from 0 to 9, count how many times that digit appears across all numbers in the range.	Easy2	ImplementationBrute force	No attempts yet	1s	1024 MB	Judgeable
Judging Assistant for ContestGiven a submission's filename, return code, timing, and output, print one of five verdicts for it.	Easy2	ImplementationString	No attempts yet	1s	1024 MB	Judgeable
A Game Called MindGiven each player's sorted cards, print the player letter for every card in ascending order of card value.	Easy2	SortingArray	No attempts yet	1s	1024 MB	Judgeable
Parity of StringsGiven a lowercase string, decide whether every letter appears an even number of times, every letter appears an odd number of times, or neither.	Easy2	ArrayImplementation	No attempts yet	1s	1024 MB	Judgeable
Simplified KeyboardGiven two lowercase words, decide whether they are identical, similar (same length, each letter matches or is a keyboard neighbor), or different.	Easy2	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Hi Cleopatra, the Best Potato Chip in the WorldGiven each player's maximum pitch, simulate the circle where the pitch rises by 1 per turn and find the first player whose maximum is exceeded.	Easy2	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable
Polar Bear Tears BracketsGiven a bracket string S of length N, find the fewest days Hyeop needs to build it by inserting O or X each night, or print -1 if it cannot be built.	Easy2	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Find the TwinsFor each set of 10 distinct jersey numbers, report whether 18 (Mack), 17 (Zack), both, or neither appears in the set.	Easy2	ImplementationArray	No attempts yet	1s	1024 MB	Judgeable
Brownies vs. Candies vs. CookiesFor each practice, double the brownie count whenever a group is at least as large as the remaining brownies, then print the count left after each group takes one.	Easy2	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable