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Total results2,362 problems

Chicken Dance Gomgomi Ims 2
Easy2
Implementation, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Redistributing the Setting Fees
Easy2
Array, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Vertical Calendar
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Identify, Sort, Index, Solve
Easy2
Sorting, Implementation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
HCPC 2022 Problem Setting
Easy2
Brute force, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Finding Maximal Non-Trivial Monotones
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Big Data? Information Security!
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Mentors and Mentees
Easy2
Sorting, String
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Vowel Count
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Soccer Standings
Easy2
Brute force, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Buying in Bulk
Easy2
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Are We Stopping Again?
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Fold the Paper Nicely
Easy2
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Good Coin Denomination
Easy2
Array, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
XO
Easy2
Implementation, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Adria
Easy2
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Walktober
Easy2
Array, Implementation
No attempts yet
Time limit
Not set
Memory limit
1024 MB
Judgeable
Curling
Easy2
Implementation, Math
No attempts yet
Time limit
20s
Memory limit
1024 MB
Judgeable
Big Number
Easy2
Implementation, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Snowflakes
Easy2
Implementation, Array
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Rhonda
Easy2
Implementation, Matrix
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
V for Vendetta
Easy2
Implementation, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Continuous?
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Limit of a Sequence Ratio
Easy2
Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Reverse
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Square
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Quadratics
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Ornaments
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Zero
Easy2
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Draw
Easy2
Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Friends
Easy2
Sorting, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Presidents
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Time Limits
Easy2
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Date
Easy2
Implementation, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Bomb
Easy2
Matrix, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Scale
Easy2
Array, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Playtime
Easy2
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Floor Cleaner
Easy2
Implementation, Sorting
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Palindrome
Easy2
Two pointers, String
No attempts yet
Time limit
5s
Memory limit
4 MB
Judgeable
Growth Potion Selection Ticket
Easy2
Implementation, Brute force
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Choosing Problems
Easy2
Hash map, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
A+B
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Farm
Easy2
Math, Implementation
No attempts yet
Time limit
0.15s
Memory limit
1024 MB
Judgeable
Oczko
Easy2
Implementation, String
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Horizontal Hearts
Easy2
Implementation, String
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Alternating word
Easy2
String, Greedy
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Non Classical Problem
Easy2
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
New Time
Easy2
Brute force, Math+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Kent-buggen
Easy2
Hash map, String
No attempts yet
Time limit
6s
Memory limit
1024 MB
Judgeable
The Train Switch
Easy2
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Viking Hackers
Easy2
Hash map, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Skolvägen
Easy2
String, Greedy
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Lamps
Easy2
Simulation, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Chocolate Box
Easy2
Array, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Pyramid Construction
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Tomatoes
Easy2
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Refrigerator Transport
Easy2
Brute force, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Bovine Birthday
Easy2
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Morning Exercises
Easy2
Array, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
ISBN
Easy2
Brute force, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Vertical Histogram
Easy2
Array, Implementation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Making Change
Easy2
Greedy, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Special Chicken Distribution
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Square Designs
Easy2
Implementation, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Ice Cream
Easy2
Array, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Word Diamonds
Easy2
Implementation, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Crossword Puzzle Words
Easy2
Implementation, Matrix
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
No Thanks!
Easy2
Array, Implementation
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Halli Galli
Easy2
Implementation, Hash map
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Meeting Near the Fountain
Easy2
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Grid Drawing
Easy2
Implementation, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Robinson Crusoe
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Rhombus
Easy2
Implementation, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Adjacent Colors
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Weightlifter
Easy2
Implementation, Array
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Ladder of Numbers
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Divisions
Easy2
Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Colorful Diagonals
Easy2
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Old English
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
FHL Final
Easy2
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
PE Class
Easy2
Sorting, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Linear Regression Is Too Easy 1
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Three-Legged Race
Easy2
Array, Hash map
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Score
Easy2
Simulation, Hash map
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
JOI Editor
Easy2
String, Simulation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Estimathon
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Class Field Trip
Easy2
Sorting, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Ghost Leg
Easy2
Simulation, Array
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Factorial 3
Easy2
Math, Implementation
No attempts yet
Time limit
4s
Memory limit
1024 MB
Judgeable
Honeycomb 2
Easy2
Math, Implementation
No attempts yet
Time limit
0.25s
Memory limit
1024 MB
Judgeable
Gorani Command
Easy2
Brute force, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Non-Prime Number
Easy2
Math, Implementation
No attempts yet
Time limit
0.5s
Memory limit
1024 MB
Judgeable
Cancel the Trains
Easy2
Array, Two pointers
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Hotelier
Easy2
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
One and Two
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
KartRider: Drift
Easy2
Sorting, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Absolute Difference Sequence
Easy2
Simulation, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Blueberry Waffle
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Fading Wind
Easy2
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Hunt the Wumpus
Easy2
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Chicken Dance Gomgomi Ims 2Given N gifticons with remaining validity written as D-x, count how many have x of 90 or less.	Easy2	ImplementationString	No attempts yet	1s	1024 MB	Judgeable
Redistributing the Setting FeesGiven each setter's fee and the amounts they hand to others, compute the final money of all N+M staff members.	Easy2	ArrayImplementation	No attempts yet	1s	256 MB	Judgeable
Vertical CalendarGiven year N and the weekday of January 1, count the calendar columns that have 5 cells across the months of that year.	Easy2	MathImplementation	No attempts yet	1s	512 MB	Judgeable
Identify, Sort, Index, SolveGiven N problem titles with numbers and difficulties, sort them by number and output the uppercased D-th character of each title in that order.	Easy2	SortingImplementation+1	No attempts yet	1s	512 MB	Judgeable
HCPC 2022 Problem SettingGiven the fee for each difficulty from 1 to 5, find the maximum total fee under two limits on the weighted sum of chosen problems.	Easy2	Brute forceImplementation	No attempts yet	1s	512 MB	Judgeable
Finding Maximal Non-Trivial MonotonesGiven a string of a and b characters, count the a characters that lie in maximal runs of equal letters with length at least 2.	Easy2	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Big Data? Information Security!Given a string that concatenates the words bigdata and security, count each word's occurrences and print which one appears more often, or that they tie.	Easy2	StringImplementation	No attempts yet	1s	256 MB	Judgeable
Mentors and MenteesSort mentor-mentee pairs by mentor in dictionary order, and break ties by mentee in reverse dictionary order.	Easy2	SortingString	No attempts yet	2s	256 MB	Judgeable
Vowel CountFor each lowercase name, print the name, then 1 if it has more vowels (aeiou) than consonants, otherwise 0.	Easy2	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Soccer StandingsGiven each team's games played and points, list every win-tie-loss record that produces those points, sorted by wins in descending order.	Easy2	Brute forceImplementation	No attempts yet	1s	1024 MB	Judgeable
Buying in BulkGiven item count c and unit price p for each customer, compute the total cost when every item after the first gets a $2 discount.	Easy2	ImplementationMath	No attempts yet	1s	1024 MB	Judgeable
Are We Stopping Again?Given the trip length and the gas and food intervals in miles, count the stops made before the destination, with a shared mile counted once.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Fold the Paper NicelyGiven a rectangle and a fold count, each fold halves the longer side with integer division, and the task asks for the final dimensions.	Easy2	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable
Good Coin DenominationChecks whether each coin in a sorted list of denominations is at least twice the coin before it.	Easy2	ArrayImplementation	No attempts yet	1s	1024 MB	Judgeable
XOGiven the first N moves of a tic-tac-toe game, decide whether X or O moves next, whether X or O has won, or whether the game is a draw.	Easy2	ImplementationSimulation	No attempts yet	1s	1024 MB	Judgeable
AdriaGiven the game results of N tennis sets, find Nikola's game count in set one, Josip's set wins, and the smallest G1 below G that maximizes Nikola's set wins.	Easy2	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable
WalktoberFor each day, find the highest step count among all participants, then sum how far John's last-year steps fall short of that maximum.	Easy2	ArrayImplementation	No attempts yet	Not set	1024 MB	Judgeable
CurlingCount each team's stones that touch the house and are closer to the center than every opposing stone that also touches it.	Easy2	ImplementationMath	No attempts yet	20s	1024 MB	Judgeable
Big NumberGiven a positive integer, the task prints each digit as a 4-row block drawn from a fixed font, with a blank line between digits.	Easy2	ImplementationString	No attempts yet	1s	1024 MB	Judgeable
SnowflakesFor each k by k grid of digits, decide whether it is Beautiful, Graceful, Magnificent, or Useless based on its mirror symmetry.	Easy2	ImplementationArray	No attempts yet	1s	1024 MB	Judgeable
RhondaGiven several 10x10 layers, sum the layers named in each data set cell by cell and print each resulting 10x10 grid.	Easy2	ImplementationMatrix	No attempts yet	1s	1024 MB	Judgeable
V for VendettaPrint a V shape made of stars for each input N, with the arms growing in size as N increases.	Easy2	ImplementationSimulation	No attempts yet	1s	1024 MB	Judgeable
Continuous?Given two linear pieces split at x=k, determine whether the function is continuous at k, and print f(k) if it is.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Limit of a Sequence RatioGiven a_1, a_2 and the recurrence a_i = ba_(i-1) + ca_(i-2), find the limit of a_n / a_(n-1) as n grows without bound.	Easy2	Math	No attempts yet	1s	1024 MB	Judgeable
ReverseGiven several strings with indices i and j, print each string with the characters from index i up to j-1 removed.	Easy2	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
SquareGiven words, print a square where each row is the word cyclically shifted one more position than the row above it.	Easy2	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
QuadraticsFor each data set, read the coefficients a, b, c of a quadratic equation and print both real roots rounded to the thousandths place.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
OrnamentsGiven the number of layers, find the total ornaments in a triangular pyramid where layer k holds k(k+1)/2 balls.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
ZeroGiven a zero-free integer k, find the next positive integer after k that also contains no zero digit.	Easy2	ImplementationMath	No attempts yet	1s	1024 MB	Judgeable
DrawGiven shape names, sizes, and a filled or empty flag for each data set, print the shape as ASCII art made of # characters.	Easy2	Implementation	No attempts yet	1s	1024 MB	Judgeable
FriendsGiven several datasets of friends, each with a like score, print the names sorted from highest score to lowest.	Easy2	SortingImplementation	No attempts yet	1s	1024 MB	Judgeable
PresidentsRead n lines of president last names, map each name to its bill value, and output the total dollar amount in the wallet.	Easy2	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Time LimitsFor each dataset, find the smallest whole-second time limit that is at least s times the slowest model solution's time in milliseconds.	Easy2	ImplementationMath	No attempts yet	1s	1024 MB	Judgeable
DateConvert each Month Day, Year date to MM/DD/YY, printing Invalid when the month name is misspelled or the day is outside 1 to 31.	Easy2	ImplementationString	No attempts yet	1s	1024 MB	Judgeable
BombGiven a grid of walls, empty cells, and enemies, find the empty cell where a bomb destroys the most enemies along four directions, stopped by walls.	Easy2	MatrixSimulation	No attempts yet	1s	1024 MB	Judgeable
ScaleFor each line of space-separated integers, output a new list where every value is multiplied by its neighboring values.	Easy2	ArrayImplementation	No attempts yet	1s	1024 MB	Judgeable
PlaytimeConverts each game's minutes played into years (365 days), days, hours, and minutes, printing only the units greater than 0.	Easy2	ImplementationMath	No attempts yet	1s	1024 MB	Judgeable
Floor CleanerGiven a 10 by 10 floor grid and a list of obstruction coordinates, print the locations the robot could not clean, sorted by row then column.	Easy2	ImplementationSorting	No attempts yet	1s	1024 MB	Judgeable
PalindromeRead a lowercase word of unknown or known length and print TAK if it is a palindrome, otherwise NIE, using little memory.	Easy2	Two pointersString	No attempts yet	5s	4 MB	Judgeable
Growth Potion Selection TicketGiven a character level from 200 to 239, the task is to pick the Growth Potion that lets the character reach the highest level, with ties going to the lower potion.	Easy2	ImplementationBrute force	No attempts yet	1s	1024 MB	Judgeable
Choosing ProblemsGiven the slot each idea fits, decide whether every one of the fifteen slots can be filled, with slots 5A, 5B, and 5C each needing two problems.	Easy2	Hash mapImplementation	No attempts yet	1s	1024 MB	Judgeable
A+BGiven two positive integers a and b with at most 5000 digits each, print their sum.	Easy2	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
FarmGiven the total heads X and legs Y of hens (2 legs each) and cows (4 legs each), find how many hens and cows there are.	Easy2	MathImplementation	No attempts yet	0.15s	1024 MB	Judgeable
OczkoGiven each player's card string, find the players who reach the highest score not exceeding 21, counting each Ace as 1 or 11.	Easy2	ImplementationString	No attempts yet	2s	1024 MB	Judgeable
Horizontal HeartsPrint N ASCII hearts made of at signs, placed side by side with exactly one space between each pair.	Easy2	ImplementationString	No attempts yet	5s	1024 MB	Judgeable
Alternating wordGiven a string, find the fewest letters to delete so that no two adjacent remaining letters are equal.	Easy2	StringGreedy	No attempts yet	4s	1024 MB	Judgeable
Non Classical ProblemGiven N fractions a_i/b_i, find the minimum, the maximum, and the sum of the values.	Easy2	ImplementationMath	No attempts yet	1s	1024 MB	Judgeable
New TimeGiven the clock's time and the correct time, find the fewest presses of a +1 minute button and a +1 hour button needed to match them.	Easy2	Brute forceMath+1	No attempts yet	2s	1024 MB	Judgeable
Kent-buggenGiven n artist names, count how many distinct names appear more than once.	Easy2	Hash mapString	No attempts yet	6s	1024 MB	Judgeable
The Train SwitchCount how many times the station master must flip a track switch over one day, given two trains that depart every n and m minutes.	Easy2	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable
Viking HackersSplit a binary string into 4-bit chunks, map each chunk to its character using a lookup table, and print ? for chunks with no match.	Easy2	Hash mapString	No attempts yet	1s	1024 MB	Judgeable
SkolvägenGiven a string of N, S, and B intersections, find the minimum number of side streets Cissi must cross walking from home to school on the north side.	Easy2	StringGreedy	No attempts yet	1s	1024 MB	Judgeable
LampsGiven the daily hours a lamp is on and the electricity price, find the first day the low-energy lamp's total cost drops below the incandescent bulb's.	Easy2	SimulationMath	No attempts yet	1s	1024 MB	Judgeable
Chocolate BoxCount how many times the piece count rises between consecutive observations, since each rise means a new box was bought.	Easy2	ArrayImplementation	No attempts yet	1s	1024 MB	Judgeable
Pyramid ConstructionGiven N blocks, find the largest height h whose layers 1^2 + 3^2 + ... + (2h-1)^2 use at most N blocks.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
TomatoesGiven a row of n tomatoes with three initially ripe, count how many are ripe after d days of spreading to adjacent tomatoes.	Easy2	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable
Refrigerator TransportGiven two cars with a per-trip cost and a capacity each, find the trip counts for each car that move n refrigerators at the lowest total cost.	Easy2	Brute forceMath	No attempts yet	1s	1024 MB	Judgeable
Bovine BirthdayGiven a date from 1800 or later, print its day of the week, using January 1, 1900 as a Monday and the Gregorian leap year rules.	Easy2	ImplementationMath	No attempts yet	1s	1024 MB	Judgeable
Morning ExercisesGiven a 2 x N pasture with some tree squares, find the longest run of tree-free columns and print twice its length.	Easy2	ArrayImplementation	No attempts yet	1s	1024 MB	Judgeable
ISBNGiven a 10-character ISBN with one '?', find the digit (0 to 9 or X) that makes the weighted sum divisible by 11, or print -1 if none does.	Easy2	Brute forceMath	No attempts yet	1s	1024 MB	Judgeable
Vertical HistogramCount how many times each capital letter appears in four input lines and print a vertical asterisk histogram with the alphabet below.	Easy2	ArrayImplementation+1	No attempts yet	1s	1024 MB	Judgeable
Making ChangeGiven a purchase price P in cents, output the fewest 25, 10, 5, and 1 cent coins that make change for one dollar.	Easy2	GreedyMath	No attempts yet	1s	1024 MB	Judgeable
Special Chicken DistributionGiven N pieces of each of three chicken kinds and soldier preference counts A, B, C, find the maximum number of soldiers who get their preferred chicken.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Square DesignsGiven M and N, print two square boxes side by side, the left with M cells across and the right with N, drawn with plus, minus, and I characters.	Easy2	ImplementationString	No attempts yet	1s	1024 MB	Judgeable
Ice CreamGiven N serial numbers, find the length of the longest contiguous run of even numbers in the sequence.	Easy2	ArrayImplementation	No attempts yet	1s	1024 MB	Judgeable
Word DiamondsGiven a word whose first and last letters match, print its word diamond, with the letters spreading out from the top and bottom to the middle row.	Easy2	ImplementationString	No attempts yet	1s	1024 MB	Judgeable
Crossword Puzzle WordsCount the across and down words of length two or more in a crossword grid where '-' is an empty cell and '#' is a black square.	Easy2	ImplementationMatrix	No attempts yet	1s	1024 MB	Judgeable
No Thanks!Given N sorted card numbers, sum the smallest value of each run of consecutive integers.	Easy2	ArrayImplementation	No attempts yet	0.5s	1024 MB	Judgeable
Halli GalliGiven the revealed cards, decide whether any single fruit kind totals exactly 5 across all cards so Hanbyeol should ring the bell.	Easy2	ImplementationHash map	No attempts yet	1s	1024 MB	Judgeable
Meeting Near the FountainGiven the total distance, park entrance distance, and two scooter speeds, find how many minutes late Kira arrives (rounded up), or 0 if she is on time.	Easy2	ImplementationMath	No attempts yet	1s	1024 MB	Judgeable
Grid DrawingGiven cell size k, grid width w, height h, and line thickness t, the task prints an ASCII grid of * for lines and . for cells.	Easy2	ImplementationSimulation	No attempts yet	1s	1024 MB	Judgeable
Robinson CrusoeGiven day n, print the wall record where each complete group of five days becomes a V and the leftover days appear as I.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
RhombusGiven an odd n and a range [a, b], print an n by n grid marking with * the cells whose Manhattan distance from the center is between a and b.	Easy2	ImplementationSimulation	No attempts yet	1s	1024 MB	Judgeable
Adjacent ColorsFor each circular string of R, G, and B beads, find the color pair that is adjacent most often, printing every pair that ties for the maximum.	Easy2	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
WeightlifterSum the evening-minus-morning body mass increases on training days to get the total muscle gain.	Easy2	ImplementationArray	No attempts yet	1s	1024 MB	Judgeable
Ladder of NumbersNumbers are written in a staircase with row r holding r numbers, and only the first k of each row remain; print rows a through b.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
DivisionsGiven a rating and the divisions a contest runs in, print each division the participant can enter, with an asterisk on out-of-competition entries.	Easy2	Implementation	No attempts yet	1s	1024 MB	Judgeable
Colorful DiagonalsGiven n, the task prints an n by n grid where each cell's letter depends on its distance to the nearest diagonal, cycling from a to z.	Easy2	ImplementationMath	No attempts yet	1s	1024 MB	Judgeable
Old EnglishTranslate each word by replacing s, a leading e, and oo according to three rules while keeping the case of the first letter.	Easy2	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
FHL FinalGiven the results of a best-of-n series of k games, find the earliest game after which the winner is known and mark which games were predictable.	Easy2	ImplementationMath	No attempts yet	1s	1024 MB	Judgeable
PE ClassStudents are sorted by height within each sex group, boys first, and the task is to find the largest height gap between neighbors in the row.	Easy2	SortingImplementation	No attempts yet	1s	1024 MB	Judgeable
Linear Regression Is Too Easy 1Given n points and an intercept b, find the slope a that makes the sum of (a*x_i + b - y_i) closest to 0, or print EZPZ if several slopes tie.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Three-Legged RaceGiven the team numbers of the first 2N-1 students, find the team of student 2N, which is the only team that appears once.	Easy2	ArrayHash map	No attempts yet	2s	1024 MB	Judgeable
ScoreSimulate a score that adds A_i each round and resets to 0 whenever it equals a value in B, then print the final score.	Easy2	SimulationHash map	No attempts yet	2s	1024 MB	Judgeable
JOI EditorGiven a sequence of j, o, and i key presses, the task is to output the final text after each adjacent pair of identical lowercase letters becomes uppercase.	Easy2	StringSimulation	No attempts yet	2s	1024 MB	Judgeable
EstimathonGiven the chair count of each colour, decide whether every colour can fill whole tables of four chairs so that exactly n tables are filled.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Class Field TripGiven two sorted lowercase strings, print one string that contains all their letters in alphabetical order.	Easy2	SortingString	No attempts yet	1s	1024 MB	Judgeable
Ghost LegSimulate a Ghost Leg with n vertical lines and m horizontal lines from top to bottom, then print the resulting order of the elements.	Easy2	SimulationArray	No attempts yet	1s	1024 MB	Judgeable
Factorial 3Given an integer N from 0 to 100,000, print the exact value of N! as a big integer.	Easy2	MathImplementation	No attempts yet	4s	1024 MB	Judgeable
Honeycomb 2Given room number N in a hexagonal honeycomb numbered outward from center room 1, find how many rooms lie on the shortest path from room 1 to room N, counting both ends.	Easy2	MathImplementation	No attempts yet	0.25s	1024 MB	Judgeable
Gorani CommandGiven the distances recorded along the L-shaped border of an N by M grid, find the cell whose distances match all of them.	Easy2	Brute forceImplementation	No attempts yet	1s	1024 MB	Judgeable
Non-Prime NumberGiven N, print any integer at least N that is not prime. The answer must be at most 10^9.	Easy2	MathImplementation	No attempts yet	0.5s	1024 MB	Judgeable
Cancel the TrainsGiven two sorted lists of train numbers, count how many numbers appear in both, since only trains with the same number can crash.	Easy2	ArrayTwo pointers	No attempts yet	1s	512 MB	Judgeable
HotelierSimulate customers entering a 10-room hotel from the left or right end and leaving by room number, then print which rooms are occupied at the end.	Easy2	SimulationImplementation	No attempts yet	1s	256 MB	Judgeable
One and TwoGiven a sequence of 1s and 2s, find the smallest split point k where the product of the prefix equals the product of the suffix, or report -1.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
KartRider: DriftGiven each of 8 racers' finish times and teams in a Speed Race, print which team, Red or Blue, has the higher total rank points.	Easy2	SortingImplementation	No attempts yet	1s	1024 MB	Judgeable
Absolute Difference SequenceRepeatedly replace a sequence with the absolute differences of its adjacent terms until one value remains, then print that value.	Easy2	SimulationImplementation	No attempts yet	2s	1024 MB	Judgeable
Blueberry WaffleGiven a pan that turns 180 degrees every r seconds and stops after f seconds, decide if the blueberry side faces up once the pan levels out.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Fading WindSimulate a paper airplane's height and velocity under a fading wind and output the total horizontal distance it travels.	Easy2	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable
Hunt the WumpusGiven a seeded generator that places four wumpuses on a 10x10 grid, report each guess's hit status and the Manhattan distance to the nearest remaining wumpus.	Easy2	SimulationImplementation	No attempts yet	1s	1024 MB	Judgeable