Math and counting

Number theory, combinatorics, and geometry

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Total results13,152 problems

Find the K-th Divisor
Easy2
Math, Brute force
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
AI Oven Clock
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Candy Teacher Go Changyoung
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Digit Counts in a Product
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Greatest Common Divisor and Least Common Multiple
Easy2
Math, Number theory
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
U.S. Unit Conversion
Easy2
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Laundry Owner Donghyuk
Easy2
Greedy, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Weighted Triangular Sum
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Binary Addition
Easy2
String, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Base Conversion
Easy2
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Fibonacci Number 2
Easy2
Dynamic programming, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
What Is This Semester's GPA?
Easy2
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Triangular Gimbap Price Comparison
Easy2
Math, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sugar Delivery
Easy2
Greedy, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Climbing Snail
Easy2
Math, Simulation
No attempts yet
Time limit
0.25s
Memory limit
128 MB
Judgeable
Copyright
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Dominoes
Easy2
Math, Combinatorics
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Year 2009
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Chessboard Pieces
Easy2
Math, Greedy
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Fourth Point
Easy2
Geometry, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Time Until the Warning
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Angry Changyoung
Easy2
Geometry, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
15-Puzzle Displacement
Easy2
Array, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Number Reversal
Easy2
String, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Hyunwoo the Professor
Easy2
Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Automated Telephone Exchange
Easy2
Brute force, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Flat
Easy2
Implementation, Math
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
K-Graph Oddity
Easy2
Graph, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cutting a Block
Easy2
Math, Simulation+1
No attempts yet
Time limit
2s
Memory limit
64 MB
Judgeable
Right Triangle
Easy2
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Logo
Easy2
Simulation, Geometry+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
AFC Wimbledon
Easy2
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Combination Lock
Easy2
Simulation, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Above Average
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Time Zones
Easy2
Implementation, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Dog & Gopher
Easy2
Implementation, Geometry
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
War for Middle-earth
Easy2
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tetrahedral Stacks of Cannonballs
Easy2
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bubble Gum, Bubble Gum, in the Dish, How Many Pieces Do You Wish?
Easy2
Array, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Find Multiples
Easy2
Implementation, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Number Card Game
Easy2
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Pizza Pricing
Easy2
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Quicksum
Easy2
String, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
St. Ives
Easy2
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Fifty Coats of Gray
Easy2
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Roaming Romans
Easy2
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Twin Paradox
Easy2
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Parlay Wagering
Easy2
Simulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
General Chemistry Lab
Easy2
Implementation, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Financial Management
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tire Dimensions
Easy2
String, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Next Number
Easy2
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
FIFA World Cup
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Number Guessing Game
Easy2
Implementation, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Judging Olympia
Easy2
Implementation, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Being Smarty!
Easy2
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Euclidean Clock
Easy2
Math, Geometry+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
ICPC Score Totalizer Software
Easy2
Implementation, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Savings
Easy2
Simulation, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Jean and Joe's Clothes
Easy2
Implementation, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Recipes
Easy2
Implementation, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Map Interface
Easy2
Array, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bailout Bonus
Easy2
Implementation, Hash map+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Isn't It Funny How a Bear Likes Honey?
Easy2
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Civil Engineering
Easy2
Implementation, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Aerospace & Mechanical Engineering
Easy2
Simulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Alphabet Distance
Easy2
String, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Vigenère Cipher
Easy2
String, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Stacked Floating Mountains
Easy2
Implementation, Array+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Counting Swann's Coins
Easy2
Implementation, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Fill the Rowboats!
Easy2
Implementation, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Greatest Common Divisor
Easy2
Math, Number theory+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Least Common Multiple
Easy2
Math, Number theory+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Mars Math
Easy2
Simulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Escape Route
Easy2
Brute force, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Annoying Mosquitos
Easy2
Brute force, Implementation+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Vacation Homework
Easy2
Math, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Time Card
Easy2
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Change
Easy2
Greedy, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Caesar Cipher
Easy2
String, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Triangle Validity and Classification
Easy2
Implementation, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Hailstone Sequences
Easy2
Simulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Factorial Base
Easy2
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Jingle Composing
Easy2
String, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Feynman
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Contest Timing
Easy2
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Math Practice
Easy2
Math, Brute force+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Odd or Even
Easy2
String, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Scavenger Hunt
Easy2
Math, Brute force+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Statistics
Easy2
Array, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Color Me Less
Easy2
Implementation, Brute force+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Approximating e
Easy2
Implementation, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Getting Chorded
Easy2
Implementation, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Golf
Easy2
Implementation, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Perfection
Easy2
Math, Number theory+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Ballot Evaluation
Easy2
Hash map, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Hard to Believe, but True!
Easy2
String, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Next in Line
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Speed fines are not fine!
Easy2
Implementation, Math+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Big Bang Secrets
Easy2
Implementation, String+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Find the K-th DivisorGiven N and K, find and print the K-th smallest divisor of N, or 0 if it doesn't exist.	Easy2	MathBrute force	No attempts yet	1s	128 MB	Judgeable
AI Oven ClockGiven a start time in hours, minutes, seconds and a duration in seconds, compute the finishing time on a 24-hour clock that wraps around.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Candy Teacher Go ChangyoungCheck whether the total number of candies among N students can be evenly divided among them (sum divisible by N).	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Digit Counts in a ProductGiven three 3-digit natural numbers, compute their product and count how many times each digit 0 to 9 appears in it.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Greatest Common Divisor and Least Common MultipleGiven two natural numbers up to 10000, output their greatest common divisor and least common multiple.	Easy2	MathNumber theory	No attempts yet	1s	128 MB	Judgeable
U.S. Unit ConversionConvert given values between kilograms/pounds and liters/gallons using fixed conversion factors, rounding to four decimal places.	Easy2	ImplementationMath	No attempts yet	1s	128 MB	Judgeable
Laundry Owner DonghyukGiven a number of cents, output the minimum count of quarters, dimes, nickels, and pennies using a greedy coin breakdown.	Easy2	GreedyMath+1	No attempts yet	1s	128 MB	Judgeable
Weighted Triangular SumCompute a weighted sum of triangular numbers W(n) for up to 300 test cases using a direct formula or loop.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Binary AdditionAdd two binary strings up to length 80 for multiple test cases and print the sum without leading zeros.	Easy2	StringSimulation+1	No attempts yet	1s	128 MB	Judgeable
Base ConversionConvert a number given in an arbitrary base (2 to 36, using letters for digits above 9) into its decimal value.	Easy2	MathImplementation+1	No attempts yet	1s	128 MB	Judgeable
Fibonacci Number 2Compute the nth Fibonacci number for n up to 90.	Easy2	Dynamic programmingMath	No attempts yet	1s	128 MB	Judgeable
What Is This Semester's GPA?Compute a weighted GPA from a list of courses, credits, and letter grades, rounded to two decimal places.	Easy2	ImplementationMath	No attempts yet	1s	128 MB	Judgeable
Triangular Gimbap Price ComparisonGiven several price rates for gimbap, compute the cheapest cost to buy exactly 1000 grams using the best per-gram rate among all stores.	Easy2	MathGreedy+1	No attempts yet	1s	128 MB	Judgeable
Sugar DeliveryFind the minimum number of 3kg and 5kg bags that sum to exactly N kilograms, or -1 if impossible.	Easy2	GreedyMath	No attempts yet	1s	128 MB	Judgeable
Climbing SnailCompute the number of days for a snail climbing A meters by day and sliding B meters by night to reach a pole of height V.	Easy2	MathSimulation	No attempts yet	0.25s	128 MB	Judgeable
CopyrightGiven A songs and a rounded-up average I, find the smallest total copyrighted melodies consistent with ceil(total/A) = I.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
DominoesGiven N, compute the total dot count across all unique dominoes with halves ranging from 0 to N.	Easy2	MathCombinatorics	No attempts yet	1s	128 MB	Judgeable
Year 2009Given a day and month in the year 2009, output the English name of the weekday for that date.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Chessboard PiecesGiven N straight guillotine cuts through a rectangular board, compute the maximum number of resulting pieces.	Easy2	MathGreedy	No attempts yet	1s	128 MB	Judgeable
Fourth PointGiven three corners of an axis-aligned rectangle, compute the coordinates of the missing fourth corner.	Easy2	GeometryMath+1	No attempts yet	1s	128 MB	Judgeable
Time Until the WarningGiven current time and a future warning time in a day, compute the wait time as a difference modulo 24 hours, printing 24:00:00 if they match.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Angry ChangyoungFor each match length, decide if it fits diagonally inside a W by H rectangle and print DA or NE accordingly.	Easy2	GeometryMath+1	No attempts yet	1s	128 MB	Judgeable
15-Puzzle DisplacementCompute the total Manhattan distance of each labeled tile from its position in the solved 4x4 15-puzzle board.	Easy2	ArrayMath+1	No attempts yet	1s	128 MB	Judgeable
Number ReversalFor each number, reverse its digits, add to the original, and print YES if the sum is a palindrome, else NO.	Easy2	StringMath+1	No attempts yet	1s	128 MB	Judgeable
Hyunwoo the ProfessorFor each given N, output the number of trailing zeros in N! by counting factors of 5.	Easy2	Math	No attempts yet	1s	128 MB	Judgeable
Automated Telephone ExchangeGiven a 3-digit exchange index n, count pairs of two-digit numbers a,b (00-99) such that n - a - b = 0.	Easy2	Brute forceMath	No attempts yet	1s	128 MB	Judgeable
FlatGiven room areas and types, compute total area, total bedroom area, and flat cost using half-weighted balcony area.	Easy2	ImplementationMath	No attempts yet	3s	256 MB	Judgeable
K-Graph OddityCompute the maximum vertex degree in a graph and output the smallest odd integer greater than or equal to it.	Easy2	GraphImplementation+1	No attempts yet	1s	128 MB	Judgeable
Cutting a BlockGiven a box and n, print the coordinates of n equal slabs formed by evenly spaced cuts along the x-axis, each rounded to 8 decimals.	Easy2	MathSimulation+1	No attempts yet	2s	64 MB	Judgeable
Right TriangleRead triples of side lengths until 0 0 0, and print right if the squares of the two shorter sides sum to the square of the longest, else wrong.	Easy2	MathImplementation+2	No attempts yet	1s	128 MB	Judgeable
LogoTrack a turtle's position and heading through forward, backward, left, and right commands, then report the rounded distance from the start.	Easy2	SimulationGeometry+2	No attempts yet	1s	128 MB	Judgeable
AFC WimbledonGiven the sum and difference of two non-negative scores, print the larger score first, or -1 if no such scores exist.	Easy2	MathImplementation+1	No attempts yet	1s	128 MB	Judgeable
Combination LockGiven the dial position and three combination numbers, sum the degrees turned clockwise and counter-clockwise to open the lock.	Easy2	SimulationMath+1	No attempts yet	1s	128 MB	Judgeable
Above AverageFor each class, compute the average score and print the percentage of students scoring strictly above it, rounded to three decimals.	Easy2	MathImplementation	No attempts yet	1s	256 MB	Judgeable
Time ZonesGiven a time and two time zone abbreviations, compute the equivalent wall-clock time in the second zone.	Easy2	ImplementationMath+1	No attempts yet	1s	128 MB	Judgeable
Dog & GopherGiven the gopher's position, the dog's position, and a list of holes, find the first hole the gopher reaches no later than the dog.	Easy2	ImplementationGeometry	No attempts yet	1s	128 MB	Judgeable
War for Middle-earthFor each battle, compute the weighted score of both armies from six and seven race counts and report the winner or a tie.	Easy2	ImplementationMath	No attempts yet	1s	128 MB	Judgeable
Tetrahedral Stacks of CannonballsFor each of n queries, read the base side length and print the problem number, the side length, and the total cannonballs in a tetrahedral stack of that size.	Easy2	MathImplementation+1	No attempts yet	1s	128 MB	Judgeable
Bubble Gum, Bubble Gum, in the Dish, How Many Pieces Do You Wish?Given a list of names arranged in a circle, a starting person, and a count n, find who is at position n in the count.	Easy2	ArraySimulation+1	No attempts yet	1s	128 MB	Judgeable
Find MultiplesRead n, then read numbers until a sentinel 0, printing for each whether it is a multiple of n.	Easy2	ImplementationMath+1	No attempts yet	1s	128 MB	Judgeable
Number Card GameFor each starting number S, repeatedly replace it with the product of its digits until a single digit appears, printing every value in order.	Easy2	SimulationImplementation+2	No attempts yet	1s	128 MB	Judgeable
Pizza PricingFor each menu of pizzas, find the diameter of the pizza with the lowest cost per square inch.	Easy2	ImplementationMath	No attempts yet	1s	128 MB	Judgeable
QuicksumCompute a weighted checksum for each input line: sum each character's 1-based position times its letter value, where spaces count as 0, until a line with only #.	Easy2	StringImplementation+2	No attempts yet	1s	128 MB	Judgeable
St. IvesFor each floating-point n until a terminating 0, print 1 + n + n^2 + n^3 + n^4 rounded to two decimals.	Easy2	MathImplementation+2	No attempts yet	1s	128 MB	Judgeable
Fifty Coats of GrayGiven room dimensions, opening sizes, and the area one can covers, compute the total paintable area for n apartments and round up to whole cans.	Easy2	MathImplementation+2	No attempts yet	1s	128 MB	Judgeable
Roaming RomansConvert each English-mile distance into Roman miles and paces using a fixed ratio, rounding the pace count to the nearest integer.	Easy2	MathImplementation+2	No attempts yet	1s	128 MB	Judgeable
The Twin ParadoxGiven Earth time and spaceship time, compute the ship's average speed as a fraction of light speed and print it to three decimals.	Easy2	MathImplementation+2	No attempts yet	1s	128 MB	Judgeable
Parlay WageringSimulate a sequence of parlay wagers: apply each money-line multiplier with truncation, skip ties, and format the final payout with commas.	Easy2	SimulationImplementation+1	No attempts yet	1s	128 MB	Judgeable
General Chemistry LabGiven a sequence of temperatures ending with 999, print each temperature's difference from the previous one, rounded to two decimals.	Easy2	ImplementationMath+1	No attempts yet	1s	128 MB	Judgeable
Financial ManagementGiven twelve monthly closing balances, compute the mean and print it rounded to the nearest penny with a dollar sign.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Tire DimensionsParse a tire size code and compute its overall circumference from the section width, aspect ratio, and rim diameter.	Easy2	StringImplementation+1	No attempts yet	1s	128 MB	Judgeable
Next NumberGiven three distinct integers from an arithmetic or geometric progression, decide which type it is and print the label with the next term.	Easy2	MathImplementation+2	No attempts yet	1s	128 MB	Judgeable
FIFA World CupGiven groups, teams per group, advancers per group, and byes, compute total matches played plus teams padded to the next power of two.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Number Guessing GameFor each n0, report whether 3n0 is odd or even and print n4, the quotient of (n23)/9.	Easy2	ImplementationMath+1	No attempts yet	1s	128 MB	Judgeable
Judging OlympiaFor each line of six judge grades, discard the highest and lowest and print the average of the remaining four, stopping at the all-zero line.	Easy2	ImplementationMath+1	No attempts yet	1s	128 MB	Judgeable
Being Smarty!Given row R and block size N, decide whether the alternating style property P1 or P2 applies to that row.	Easy2	MathImplementation+1	No attempts yet	1s	128 MB	Judgeable
The Euclidean ClockGiven two clock times and a radius, find the area of the sector swept by the hour hand between them.	Easy2	MathGeometry+1	No attempts yet	1s	128 MB	Judgeable
ICPC Score Totalizer SoftwareFor each contestant, drop one highest and one lowest judge score, then output the truncated average of the rest.	Easy2	ImplementationSorting+2	No attempts yet	1s	128 MB	Judgeable
SavingsFor each test case, print how many years of multiplying the balance by (1 + B/100) are needed until it first exceeds M.	Easy2	SimulationMath+2	No attempts yet	1s	128 MB	Judgeable
Jean and Joe's ClothesRead clothing sizes and count how many items go to Joe, Jean, Jane, James, or no one, per visit until N equals 0.	Easy2	ImplementationSimulation+2	No attempts yet	1s	128 MB	Judgeable
RecipesMultiply each recipe amount by a constant and print the result as a reduced integer or mixed fraction.	Easy2	ImplementationMath+1	No attempts yet	1s	128 MB	Judgeable
Map InterfaceGiven station coordinates and a visited sequence, count how many stations fall inside the smallest axis-aligned rectangle covering the visited stations.	Easy2	ArrayImplementation+2	No attempts yet	1s	128 MB	Judgeable
Bailout BonusGiven a list of bailed-out companies, a tax rate, and executives with company and bonus, sum the floor of the taxed fraction for executives at bailed companies.	Easy2	ImplementationHash map+2	No attempts yet	1s	128 MB	Judgeable
Isn't It Funny How a Bear Likes Honey?Given Pooh's weight and the radii of several spherical helium balloons, decide whether their combined lift strictly exceeds his weight.	Easy2	MathImplementation+2	No attempts yet	1s	128 MB	Judgeable
Civil EngineeringRead material densities and oblong dimensions, then sum each oblong's volume times its material density for each data set.	Easy2	ImplementationMath+2	No attempts yet	1s	128 MB	Judgeable
Aerospace & Mechanical EngineeringGiven each stage's mass, burn time, and thrust, simulate the rocket's vertical motion and report its height when the last stage falls off.	Easy2	SimulationImplementation+1	No attempts yet	1s	128 MB	Judgeable
Alphabet DistanceFor each test case, read two equal-length uppercase words and print the alphabet distance between the paired letters at every position.	Easy2	StringImplementation+1	No attempts yet	1s	128 MB	Judgeable
Vigenère CipherEncrypt each given plaintext with the Vigenère cipher, shifting every letter by the aligned repeated keyword letter modulo 26.	Easy2	StringImplementation+1	No attempts yet	1s	128 MB	Judgeable
Stacked Floating MountainsGiven several sequences, decide for each whether every element from the third onward equals the sum of the two before it.	Easy2	ImplementationArray+1	No attempts yet	1s	128 MB	Judgeable
Counting Swann's CoinsPrint numbers 1 through N, replacing multiples of 3 with Dead, of 5 with Man, and of 15 with DeadMan, breaking the line after each word.	Easy2	ImplementationMath+1	No attempts yet	1s	128 MB	Judgeable
Fill the Rowboats!Print the numbers 1 through N, inserting the word Go! after every sixth number and after the last one.	Easy2	ImplementationSimulation+1	No attempts yet	1s	128 MB	Judgeable
Greatest Common DivisorRead n pairs of positive integers and print the greatest common divisor of each pair on its own line.	Easy2	MathNumber theory+1	No attempts yet	1s	128 MB	Judgeable
Least Common MultipleFor each of n test cases, read two natural numbers a and b and print their least common multiple.	Easy2	MathNumber theory+1	No attempts yet	1s	128 MB	Judgeable
Mars MathEvaluate a chain of at most three Mars operations (@, %, #) on a starting number and print the result to two decimals.	Easy2	SimulationImplementation+1	No attempts yet	1s	128 MB	Judgeable
Escape RouteGiven your position and n-1 planet positions, find the closest planet, print both coordinates, and print the distance rounded to two decimals.	Easy2	Brute forceMath+1	No attempts yet	1s	128 MB	Judgeable
Annoying MosquitosGiven up to 100 mosquito positions and up to 10000 swat centers, count how many mosquitos fall within the 101x101 square of at least one swat.	Easy2	Brute forceImplementation+1	No attempts yet	1s	256 MB	Judgeable
Vacation HomeworkGiven L vacation days and per-day limits C and D, find the most free days after finishing A Korean and B math pages.	Easy2	MathGreedy+1	No attempts yet	1s	128 MB	Judgeable
Time CardGiven clock-in and clock-out times for three employees in h m s form, print each employee's working duration as hours, minutes, and seconds.	Easy2	MathImplementation+1	No attempts yet	1s	128 MB	Judgeable
ChangeGiven a purchase amount below 1000 yen paid with a 1000-yen bill, find the minimum number of coins in the change.	Easy2	GreedyMath+1	No attempts yet	1s	128 MB	Judgeable
Caesar CipherGiven an uppercase word encrypted by shifting each letter forward three positions, shift every letter back by three to recover the original.	Easy2	StringImplementation+2	No attempts yet	1s	128 MB	Judgeable
Triangle Validity and ClassificationRead lines of three side lengths, count valid triangles as right, acute, or obtuse, and stop at the first line that is not a triangle.	Easy2	ImplementationMath+2	No attempts yet	1s	128 MB	Judgeable
Hailstone SequencesFor each starting value H up to 500, simulate the Collatz rule and print the largest number that appears before reaching 1.	Easy2	SimulationImplementation+1	No attempts yet	1s	128 MB	Judgeable
Factorial BaseRead each factorial-base number, weight digit at position i (from the right, 1-indexed) by i!, and print the decimal value.	Easy2	MathImplementation+1	No attempts yet	1s	128 MB	Judgeable
Jingle ComposingSplit a slash-delimited composition into measures and count how many note durations sum exactly to 1.	Easy2	StringImplementation+1	No attempts yet	1s	128 MB	Judgeable
FeynmanFor each N, count all axis-aligned squares contained in an N by N grid of unit cells, ending at the sentinel 0.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Contest TimingShe starts at 11:11 on 11/11. Given the day, hour, and minute she stops, print the minutes elapsed, or -1 if the stop is earlier.	Easy2	MathImplementation+1	No attempts yet	1s	128 MB	Judgeable
Math PracticeGiven A (0 to 45) and B (1 to 9), find the smallest E in 1 to 62 with E > A and 2^E starting with digit B, or 0 if none exists.	Easy2	MathBrute force+1	No attempts yet	1s	128 MB	Judgeable
Odd or EvenRead N large integers up to 10^60 and print odd or even for each, judging parity from the last digit.	Easy2	StringMath+2	No attempts yet	1s	128 MB	Judgeable
Scavenger HuntList every pair (x, y) where x divides P and y divides Q, sorted by x then y.	Easy2	MathBrute force+1	No attempts yet	1s	128 MB	Judgeable
StatisticsRead N integers, print their mean and median rounded to six decimal places.	Easy2	ArraySorting+2	No attempts yet	1s	128 MB	Judgeable
Color Me LessRead 16 target RGB colors, then map each following color to the nearest target color by Euclidean distance, breaking ties by earliest appearance.	Easy2	ImplementationBrute force+2	No attempts yet	1s	128 MB	Judgeable
Approximating ePrint approximations of e for n from 0 to 9, each rounded to 9 decimals with trailing zeros removed, under a fixed two-line header.	Easy2	ImplementationMath+1	No attempts yet	1s	128 MB	Judgeable
Getting ChordedGiven three note names, decide whether their semitone spacing forms a major or minor chord, then print the echo with the root-named chord or "unrecognized".	Easy2	ImplementationMath+1	No attempts yet	1s	128 MB	Judgeable
GolfFor each test case, turn a hole's par and John's stroke count into the standard golf score name, with hole-in-one taking priority.	Easy2	ImplementationMath+2	No attempts yet	1s	128 MB	Judgeable
PerfectionFor each number below 60000, sum its proper divisors and classify it as perfect, deficient, or abundant.	Easy2	MathNumber theory+1	No attempts yet	1s	128 MB	Judgeable
Ballot EvaluationSum the given parties' vote percentages and check the sum against an integer n using the guess's comparison operator.	Easy2	Hash mapImplementation+1	No attempts yet	1s	128 MB	Judgeable
Hard to Believe, but True!Read the numbers in each equation backwards, add them, and check whether the sum equals the backwards-read result.	Easy2	StringMath+1	No attempts yet	1s	128 MB	Judgeable
Next in LineGiven the ages of the youngest and middle of three children in an arithmetic sequence, print the oldest child's age.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Speed fines are not fine!Given a speed limit and a recorded speed, decide whether the car is speeding and print the matching fine from a three-tier table.	Easy2	ImplementationMath+2	No attempts yet	2s	512 MB	Judgeable
Big Bang SecretsDecode an uppercase word by shifting each letter backward by S = 3P + K positions, where P is the letter's 1-based position.	Easy2	ImplementationString+1	No attempts yet	2s	512 MB	Judgeable