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Loops, arithmetic, I/O. Start here

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Total results2,362 problems

Who Is the Admin?
Easy2
Implementation, Array+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Credit Card Validation
Easy2
Implementation, String+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Paint Estimate
Easy2
Math, Implementation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Stacking Cups
Easy2
Sorting, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Advertising Revenue
Easy2
Implementation, Simulation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Bedtime Reading I
Easy2
Math, Number theory+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Uphill
Easy2
Array, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Term index in an arithmetic sequence
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Sharing apples and bananas
Easy2
Math, Number theory+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Base converter
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Pepero Day 2017
Easy2
Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Building a distribution table
Easy2
Implementation, Array+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
The 3n+1 Sequence
Easy2
Simulation, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Von Neumann and the Fly
Easy2
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Soccer Skills
Easy2
Implementation, Geometry+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
I Work All Day
Easy2
Implementation, Brute force+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Just A Minim
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Qualifiers for the Next Phase
Easy2
Sorting, Array+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Coffee Machine
Easy2
Brute force, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Happy Trails
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Arggggggh!
Easy2
Implementation, Math+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Life Savings
Easy2
Brute force, Math+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Nine Knights
Easy2
Implementation, Simulation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Batter Up
Easy2
Implementation, Math+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
No Duplicates
Easy2
String, Hash map+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Latin Squares
Easy2
Implementation, Array+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Congruent Numbers
Easy2
Math, Number theory+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Boolean Satisfiability
Easy2
Combinatorics, Math+2
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Atomic Mass
Easy2
String, Hash map+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Incomplete Book
Easy2
Math, Simulation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Analysis of Advanced Analytics
Easy2
Simulation, Greedy+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Grass Cutting
Easy2
Simulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Jousting Tournament
Easy2
Implementation, Simulation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Kiwis vs Kangaroos
Easy2
Implementation, String+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Beautiful Music
Easy2
Implementation, String+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Letter Count
Easy2
String, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Recently Used Documents
Easy2
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Pirates
Easy2
String, Hash map+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Password check
Easy2
String, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Opening Ceremony
Easy2
Array, Implementation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Triple Jump
Easy2
Implementation, Array
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Hissing Microphone
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Sum Squared Digits Function
Easy2
Math, Implementation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Santa's Gifts
Easy2
Math, Geometry+2
No attempts yet
Time limit
5s
Memory limit
512 MB
Judgeable
Life Score
Easy2
String, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Big number A+B
Easy2
String, Math+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
A Simple Problem
Easy2
Math, Implementation+1
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Check the Check
Easy2
Implementation, String+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Shattered Cake
Easy2
Math, Implementation+2
No attempts yet
Time limit
10s
Memory limit
512 MB
Judgeable
Triangles from Five Sticks
Easy2
Brute force, Geometry+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Jaccard Similarity Threshold
Easy2
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Pencils
Easy2
Math, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Array Manipulation at Moloco (Easy)
Easy2
Array, Brute force
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Lorem ipsum
Easy2
String, Implementation+1
No attempts yet
Time limit
0.1s
Memory limit
512 MB
Judgeable
Hash collision strings
Easy2
String, Hash map+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Abbey Courtyard
Easy2
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Cube Bits
Easy2
Math, Implementation
No attempts yet
Time limit
4s
Memory limit
512 MB
Judgeable
Binary Game
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Sum of Divisors
Easy2
Math, Brute force
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Lotto number frequency
Easy2
Implementation, Array
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Is N prime
Easy2
Math, Number theory+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Rick
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Midterm Exam Grading
Easy2
Implementation, Array+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Exceed or not
Easy2
Math, Implementation+1
No attempts yet
Time limit
0.5s
Memory limit
128 MB
Judgeable
Derivative of a polynomial function
Easy2
String, Implementation+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Master Manager Nam Jeonghun
Easy2
Math, Greedy
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Magic Square
Easy2
Implementation, Matrix+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Teleportation
Easy2
Math, Implementation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Jealous Jinseo
Easy2
Implementation, Array
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
PLAYERJINAH’S BOTTLEGROUNDS
Easy2
Geometry, Math+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Master of the Shell Game
Easy2
String, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Overflow and Modulo
Easy2
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
What Is Your Handle
Easy2
Sorting, String+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
It Worked, So Why Is It Wrong?
Easy2
Implementation, Simulation+2
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Hashing
Easy2
Implementation, Math
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Matrix Multiplication Calculator
Easy2
Implementation, Matrix+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Wak Sani Satay
Easy2
Implementation, Math
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Caesar Cipher
Easy2
String, Implementation+1
No attempts yet
Time limit
1s
Memory limit
64 MB
Judgeable
What Does UCPC Stand For?
Easy2
String, Greedy+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Mannequins on the Tracks!!
Easy2
Simulation, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Suchan Is a Marine Boy!!
Easy2
Math, Implementation+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Prize Hunter
Easy2
Implementation, Array
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Happiness
Easy2
Array, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Telemarketer or not?
Easy2
Implementation, Brute force
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Occupy Parking
Easy2
String, Implementation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Are we there yet?
Easy2
Array, Prefix sum+2
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Income Inequality
Easy2
Array, Implementation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Larger Sport Facility
Easy2
Implementation, Math
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
What Is Today's Date?
Easy2
Implementation
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Baby Bites
Easy2
Implementation, String
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Luka
Easy2
Implementation, Simulation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Pascal's Triangle
Easy2
Math, Combinatorics+2
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Poker Hand
Easy2
Hash map, Implementation
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Sculpture
Easy2
Array, Implementation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Setting a Time Limit
Easy2
Math, Implementation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Bessie and Daisy
Easy2
Math, Geometry+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Unraveling Monty Hall
Easy2
Math, Simulation+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
CPU
Easy2
Implementation, String
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Tour de BINUS
Easy2
Array, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Contemporary Art
Easy2
Math
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Who Is the Admin?Given nine clubs with N members each, find the club whose best member solved more problems than the best member of every other club.	Easy2	ImplementationArray+1	No attempts yet	1s	256 MB	Judgeable
Credit Card ValidationFor each 16-digit card number, apply the Luhn checksum (double every second digit from the right, sum digits) and print T if the total is divisible by 10, else F.	Easy2	ImplementationString+1	No attempts yet	1s	128 MB	Judgeable
Paint EstimateFor each floor plan, compute the paintable wall and ceiling area minus window and door areas, multiply by the number of apartments, and round the total up by the coverage of one can.	Easy2	MathImplementation+2	No attempts yet	2s	512 MB	Judgeable
Stacking CupsRead each cup's message, recover its radius from either token order, then print colors from smallest to largest cup.	Easy2	SortingImplementation	No attempts yet	1s	512 MB	Judgeable
Advertising RevenueFor each data set, sum the payments for every display ad shown and every clickthrough ad clicked, then print the total.	Easy2	ImplementationSimulation	No attempts yet	2s	512 MB	Judgeable
Bedtime Reading IGiven an integer I, compute the sum of all its divisors.	Easy2	MathNumber theory+1	No attempts yet	2s	512 MB	Judgeable
UphillRead all integers on one line and print Good if they are in non-decreasing order, otherwise Bad.	Easy2	ArrayImplementation	No attempts yet	2s	512 MB	Judgeable
Term index in an arithmetic sequenceGiven a first term, a common difference, and a value k, print the 1-based position of k in the arithmetic sequence, or X if k is absent.	Easy2	MathImplementation	No attempts yet	2s	512 MB	Judgeable
Sharing apples and bananasGiven a apples and b bananas, print every common divisor n of a and b with the per-friend apple and banana counts.	Easy2	MathNumber theory+1	No attempts yet	2s	512 MB	Judgeable
Base converterConvert a decimal integer m into base n (2 to 16), using A-F for digits 10 and above.	Easy2	MathImplementation	No attempts yet	2s	512 MB	Judgeable
Pepero Day 2017Given a time on November 11, 2017, print the Pepero count from the reward rules based on the hour, minute, and second.	Easy2	Implementation	No attempts yet	2s	512 MB	Judgeable
Building a distribution tableGiven real numbers in [0,1), count how many fall into each of m equal-length subintervals and print the counts in order.	Easy2	ImplementationArray+1	No attempts yet	1s	512 MB	Judgeable
The 3n+1 SequenceStarting from the given first term, apply the 3n+1 rule until the value first hits 1 and report that position.	Easy2	SimulationMath+1	No attempts yet	1s	512 MB	Judgeable
Von Neumann and the FlyGiven train speed S, fly speed T, and initial gap D, compute how far the fly travels before the two trains collide.	Easy2	MathImplementation+2	No attempts yet	1s	512 MB	Judgeable
Soccer SkillsAmong all teammates whose distance from you is between a and b, print the position, distance, and angle of the one with smallest x then smallest y.	Easy2	ImplementationGeometry+1	No attempts yet	2s	512 MB	Judgeable
I Work All DayGiven a list of saw settings and a tree height T, pick the setting H that minimizes T mod H, breaking ties by first appearance.	Easy2	ImplementationBrute force+1	No attempts yet	1s	512 MB	Judgeable
Just A MinimGiven a list of note codes, sum their lengths in semibreves and print the exact value.	Easy2	MathImplementation	No attempts yet	2s	512 MB	Judgeable
Qualifiers for the Next PhaseGiven N scores and a minimum cutoff rank K, count how many competitors advance when ties at the K-th score also qualify.	Easy2	SortingArray+1	No attempts yet	1s	1024 MB	Judgeable
Coffee MachineGiven the number of employees on each of three floors, pick the floor for one coffee machine that minimizes total daily stair time.	Easy2	Brute forceMath+1	No attempts yet	1s	1024 MB	Judgeable
Happy TrailsGiven trail sections as angles and distances, compute the total elevation change and print it rounded to two decimals.	Easy2	MathImplementation	No attempts yet	2s	512 MB	Judgeable
Arggggggh!Follow a start point and a series of compass moves to compute the final coordinates, rounded to 8 decimals.	Easy2	ImplementationMath+1	No attempts yet	2s	512 MB	Judgeable
Life SavingsCompare the savings from one 20%-style whole-purchase coupon against the best way to spend two one-item coupons on two of three items, then print the winning plan and its savings.	Easy2	Brute forceMath+2	No attempts yet	2s	512 MB	Judgeable
Nine KnightsGiven a 5x5 board, check whether it has exactly nine knights with no two attacking each other.	Easy2	ImplementationSimulation	No attempts yet	2s	512 MB	Judgeable
Batter UpRead n at-bat outcomes, sum the bases from official at-bats (0 to 4), divide by how many of them are not walks, and print the result to six decimals.	Easy2	ImplementationMath+2	No attempts yet	2s	512 MB	Judgeable
No DuplicatesRead a line of space-separated uppercase words and print yes if no word repeats, or no if any word appears more than once.	Easy2	StringHash map+1	No attempts yet	2s	512 MB	Judgeable
Latin SquaresRead an n by n grid of base-n digit characters and report whether it is a Latin square, and if so whether it is in reduced form.	Easy2	ImplementationArray+2	No attempts yet	1s	512 MB	Judgeable
Congruent NumbersGiven the two legs of a right triangle as fractions p1/q1 and p2/q2, print 1 if the triangle's area is an integer, otherwise 0.	Easy2	MathNumber theory+1	No attempts yet	2s	512 MB	Judgeable
Boolean SatisfiabilityCount the assignments of a disjunction of single literals that make the formula true, where each variable takes true or false.	Easy2	CombinatoricsMath+2	No attempts yet	3s	512 MB	Judgeable
Atomic MassParse a short chemical formula, look up each element's atomic mass, multiply by any following count, and print the total with two decimals.	Easy2	StringHash map+2	No attempts yet	1s	512 MB	Judgeable
Incomplete BookGiven the first book takes k days and each later book takes twice the previous, count how many books finish by day d.	Easy2	MathSimulation+1	No attempts yet	1s	512 MB	Judgeable
Analysis of Advanced AnalyticsGiven daily page counts and a fixed notebook size, count how many notebooks are needed when each day's notes must fit in one notebook without splitting.	Easy2	SimulationGreedy+1	No attempts yet	1s	512 MB	Judgeable
Grass CuttingAfter each week every cell grows 1 cm, then cells in the chosen rows and columns are reset to 1 cm; report the final heights of the 10x10 grid.	Easy2	SimulationImplementation+1	No attempts yet	1s	512 MB	Judgeable
Jousting TournamentPrint the fixed elimination schedule that pits competitors 1..n one by one, alternating winners between placeholders a and b.	Easy2	ImplementationSimulation	No attempts yet	2s	512 MB	Judgeable
Kiwis vs KangaroosGiven a phrase, score each side by how often its letters appear in KANGAROO or KIWIBIRD, then report the higher score or a tie.	Easy2	ImplementationString+2	No attempts yet	2s	512 MB	Judgeable
Beautiful MusicFor each note sequence, check whether every consecutive pair is 2, 4, or 6 steps apart on the repeating 7-note scale, and print one of two messages.	Easy2	ImplementationString+1	No attempts yet	2s	512 MB	Judgeable
Letter CountCount how often each English letter appears in one line, ignoring case and non-letters, then print 26 rows of stars.	Easy2	StringImplementation	No attempts yet	2s	512 MB	Judgeable
Recently Used DocumentsSimulate a most-recently-used list of capacity k: each opened document moves to the front, new ones are inserted there and the back is dropped when full, then print the final list.	Easy2	SimulationImplementation+2	No attempts yet	1s	512 MB	Judgeable
PiratesGiven a lowercase word, find the letter with the highest frequency and print that letter with its count.	Easy2	StringHash map+1	No attempts yet	2s	512 MB	Judgeable
Password checkFor each of N passwords, report valid if it has a lowercase letter, uppercase letter, digit, symbol, and length at least 12, else invalid.	Easy2	StringImplementation	No attempts yet	2s	512 MB	Judgeable
Opening CeremonyFor each data set, count how many athletes from each country marched, then report the largest shortfall against that country's registered total.	Easy2	ArrayImplementation+1	No attempts yet	2s	512 MB	Judgeable
Triple JumpFind the first step in [30.0, 30.2], then report 30.0 minus the smallest position among steps at least 3 later, or 0 if none exists.	Easy2	ImplementationArray	No attempts yet	2s	512 MB	Judgeable
Hissing MicrophoneGiven a lowercase string, check whether it contains two consecutive s characters and print hiss or no hiss.	Easy2	StringImplementation	No attempts yet	1s	512 MB	Judgeable
Sum Squared Digits FunctionFor each of P datasets, convert the given integer n to base b, square each digit, and report the total with the dataset number.	Easy2	MathImplementation+1	No attempts yet	2s	512 MB	Judgeable
Santa's GiftsCompute the total straight-line distance from Santa's house through four given points in 3D and check it does not exceed the time limit X.	Easy2	MathGeometry+2	No attempts yet	5s	512 MB	Judgeable
Life ScoreFor each name, sum the letter values (A=1 to Z=26, spaces worth 0) and print the total, or PERFECT LIFE when the total is exactly 100.	Easy2	StringImplementation	No attempts yet	2s	512 MB	Judgeable
Big number A+BRead two integers with up to 10000 digits and print their sum without leading zeros.	Easy2	StringMath+2	No attempts yet	1s	256 MB	Judgeable
A Simple ProblemGiven N, print the smallest positive multiple of N squared, which is just N squared itself.	Easy2	MathImplementation+1	No attempts yet	3s	512 MB	Judgeable
Check the CheckRead dish names and price-quantity pairs until the line TOTAL, then print PAY if the waiter's total is at most the sum of price times quantity, else PROTEST.	Easy2	ImplementationString+1	No attempts yet	2s	512 MB	Judgeable
Shattered CakeGiven the cake's width and the dimensions of all shattered rectangular pieces, sum the piece areas and divide by the width to get the length.	Easy2	MathImplementation+2	No attempts yet	10s	512 MB	Judgeable
Triangles from Five SticksGiven five distinct stick lengths, count how many 3-stick subsets can form a triangle with positive area.	Easy2	Brute forceGeometry+1	No attempts yet	2s	512 MB	Judgeable
Jaccard Similarity ThresholdGiven two small sets of digits, decide whether their Jaccard similarity is greater than 0.5.	Easy2	ImplementationMath	No attempts yet	1s	512 MB	Judgeable
PencilsChoose either set X or set Y, buy any number of copies of that one set, and pay the least to reach at least N pencils.	Easy2	MathImplementation	No attempts yet	2s	512 MB	Judgeable
Array Manipulation at Moloco (Easy)For each element, count how many earlier elements in the array are smaller, and print those counts one per line.	Easy2	ArrayBrute force	No attempts yet	2s	512 MB	Judgeable
Lorem ipsumSplit a fixed Latin placeholder paragraph into words and print the words at indices L through R separated by spaces.	Easy2	StringImplementation+1	No attempts yet	0.1s	512 MB	Judgeable
Hash collision stringsPrint two length-N strings that differ but have equal Java String hashCode values, using the classic Aa/BB collision with a shared prefix.	Easy2	StringHash map+2	No attempts yet	2s	512 MB	Judgeable
Abbey CourtyardGiven the area of a square courtyard, compute the perimeter as 4 times the square root of the area, rounded to six decimal places.	Easy2	MathImplementation+1	No attempts yet	1s	512 MB	Judgeable
Cube BitsConvert each of n decimal integers (up to 3^20) to its base-3 representation without leading zeros.	Easy2	MathImplementation	No attempts yet	4s	512 MB	Judgeable
Binary GamePrint the binary representations of 0 through n, concatenated with no separators.	Easy2	StringImplementation	No attempts yet	1s	256 MB	Judgeable
Sum of DivisorsGiven a natural number n up to 10000, print the sum of all its positive divisors, with 1 and n included.	Easy2	MathBrute force	No attempts yet	1s	256 MB	Judgeable
Lotto number frequencyGiven a number n from 1 to 45, print how often n appears among the six main winning numbers of 700 fixed Nanum Lotto rounds. The counts are precomputed constants.	Easy2	ImplementationArray	No attempts yet	1s	256 MB	Judgeable
Is N primeGiven an integer N, decide whether N is prime and print Yes or No. The trailing line of N integers is unused.	Easy2	MathNumber theory+1	No attempts yet	1s	256 MB	Judgeable
RickRead one line and print NO if it exactly matches one of six given phrases, otherwise print YES.	Easy2	StringImplementation	No attempts yet	1s	256 MB	Judgeable
Midterm Exam GradingGiven point values for N problems and each examinee's O/X results, find the highest scorer, breaking ties by the smallest exam number.	Easy2	ImplementationArray+1	No attempts yet	1s	512 MB	Judgeable
Exceed or notGiven a, b, and r, print overflow if ab exceeds r, otherwise print the product ab.	Easy2	MathImplementation+1	No attempts yet	0.5s	128 MB	Judgeable
Derivative of a polynomial functionParse a linear polynomial written like 3x+5 or -x+2 and print the constant that is its derivative.	Easy2	StringImplementation+1	No attempts yet	1s	512 MB	Judgeable
Master Manager Nam JeonghunGiven L left-footed, R right-footed, and A two-footed players, find the largest even team size with equal left and right counts.	Easy2	MathGreedy	No attempts yet	1s	128 MB	Judgeable
Magic SquareGiven an N by N matrix, decide whether its entries form a magic square with equal row, column, and diagonal sums.	Easy2	ImplementationMatrix+1	No attempts yet	1s	512 MB	Judgeable
TeleportationGiven start a, end b, and a bidirectional teleporter linking x and y, find the minimum tractor distance to move from a to b, with the option to skip the teleporter.	Easy2	MathImplementation+2	No attempts yet	2s	512 MB	Judgeable
Jealous JinseoCheck whether any person in Jinseo's row or column has higher charm than him, printing ANGRY if so and HAPPY otherwise.	Easy2	ImplementationArray	No attempts yet	1s	512 MB	Judgeable
PLAYERJINAH’S BOTTLEGROUNDSGiven the coordinates of three distinct points, decide whether they lie on a single straight line.	Easy2	GeometryMath+1	No attempts yet	1s	512 MB	Judgeable
Master of the Shell GameGiven a string, perform T swaps of characters at the given 0-indexed positions in order and print the final string.	Easy2	StringSimulation+1	No attempts yet	1s	128 MB	Judgeable
Overflow and ModuloMultiply N integers and print the product modulo M, reducing after each multiplication to avoid overflow.	Easy2	MathImplementation+2	No attempts yet	1s	512 MB	Judgeable
What Is Your HandleSort N distinct handles by ASCII dictionary order and print the I-th one.	Easy2	SortingString+1	No attempts yet	1s	512 MB	Judgeable
It Worked, So Why Is It Wrong?Compare the expected answer with Manyoung's output for each sample and system test case, then print Accepted, Wrong Answer, or Why Wrong!!! according to which group fails.	Easy2	ImplementationSimulation+2	No attempts yet	1s	512 MB	Judgeable
HashingCompute the polynomial rolling hash of a lowercase string using base 31 modulo 1234567891.	Easy2	ImplementationMath	No attempts yet	1s	512 MB	Judgeable
Matrix Multiplication CalculatorRead pairs of matrices with dimension lines, multiply them when the inner dimensions match, and print each result row wrapped in vertical bars, or print undefined.	Easy2	ImplementationMatrix+2	No attempts yet	2s	512 MB	Judgeable
Wak Sani SatayGiven daily satay and nasi impit sales, compute weekly net profit from fixed per-stick prices, meat and spice costs, and rounding to two decimals.	Easy2	ImplementationMath	No attempts yet	2s	512 MB	Judgeable
Caesar CipherShift every letter of a string by k positions in the alphabet, wrapping around, and leave spaces, periods, and commas unchanged.	Easy2	StringImplementation+1	No attempts yet	1s	64 MB	Judgeable
What Does UCPC Stand For?Given one string, decide whether deleting some characters can leave exactly the subsequence UCPC, case sensitive.	Easy2	StringGreedy+1	No attempts yet	1s	512 MB	Judgeable
Mannequins on the Tracks!!Simulate a trolley moving through three zones under a sequence of wait and lever-pull actions, and count how many mannequins get run over in zone C.	Easy2	SimulationImplementation	No attempts yet	2s	512 MB	Judgeable
Suchan Is a Marine Boy!!Given N practice records, compute the ratio of their arithmetic mean to the expected value of a value drawn uniformly from them, or print divide by zero.	Easy2	MathImplementation+2	No attempts yet	2s	512 MB	Judgeable
Prize HunterGiven two ranks a and b from two contests, print the total prize money using each contest's published prize table.	Easy2	ImplementationArray	No attempts yet	1s	512 MB	Judgeable
HappinessRead N scores and print the difference between the maximum and minimum score.	Easy2	ArrayImplementation	No attempts yet	2s	512 MB	Judgeable
Telemarketer or not?Given four digits, print "ignore" if the first and last are 8 or 9 and the middle two are equal, otherwise print "answer".	Easy2	ImplementationBrute force	No attempts yet	2s	512 MB	Judgeable
Occupy ParkingCount how many of the N parking spaces show 'C' in both the yesterday string and the today string.	Easy2	StringImplementation+1	No attempts yet	2s	512 MB	Judgeable
Are we there yet?Given four distances between consecutive cities on a line, print the full 5x5 table of distances between every pair of cities.	Easy2	ArrayPrefix sum+2	No attempts yet	2s	512 MB	Judgeable
Income InequalityFor each dataset, count how many incomes are less than or equal to the average income.	Easy2	ArrayImplementation+1	No attempts yet	2s	512 MB	Judgeable
Larger Sport FacilityCompare the areas of two rectangular sports fields and print which school's field is larger or that it is a tie.	Easy2	ImplementationMath	No attempts yet	2s	512 MB	Judgeable
What Is Today's Date?Print the current UTC year, month, and day as three lines, using the system date with no input.	Easy2	Implementation	No attempts yet	2s	128 MB	Judgeable
Baby BitesGiven n spoken words that are either "mumble" or a number, check if the i-th number equals i and output "makes sense" or "something is fishy".	Easy2	ImplementationString	No attempts yet	1s	512 MB	Judgeable
LukaGiven Luka's fixed position and a walk of unit steps, list the indices of steps after which the walker stands on Luka's cell or one of the eight neighbors.	Easy2	ImplementationSimulation	No attempts yet	1s	512 MB	Judgeable
Pascal's TriangleGiven n and k with 1 <= k <= n <= 30, print the k-th entry of row n in Pascal's triangle, equal to C(n-1, k-1).	Easy2	MathCombinatorics+2	No attempts yet	1s	256 MB	Judgeable
Poker HandGiven five distinct cards, report the largest number of cards sharing one rank.	Easy2	Hash mapImplementation	No attempts yet	2s	512 MB	Judgeable
SculptureGiven a grid of distinct neighboring heights, mark each interior cell with 1 if all four adjacent cells are higher, otherwise 0.	Easy2	ArrayImplementation+1	No attempts yet	2s	512 MB	Judgeable
Setting a Time LimitGiven n runtimes in milliseconds and a factor s, output the smallest whole number of seconds that is at least s times the largest runtime.	Easy2	MathImplementation+1	No attempts yet	2s	512 MB	Judgeable
Bessie and DaisyGiven three points on a grid, compare Bessie's 8-direction distance with Daisy's 4-direction distance to John and say who arrives first.	Easy2	MathGeometry+1	No attempts yet	1s	128 MB	Judgeable
Unraveling Monty HallCount how many of N trials hide the car behind door 2 or 3, since switching from door 1 wins exactly then.	Easy2	MathSimulation+1	No attempts yet	2s	512 MB	Judgeable
CPUGiven N assembly instructions for a 16-bit CPU, print the machine code for each one by packing opcode, register, and constant fields into their bit positions.	Easy2	ImplementationString	No attempts yet	1s	512 MB	Judgeable
Tour de BINUSSum students over Ayu's left or right walk from x1 and count zero-valued rooms over Budi's walk from x2.	Easy2	ArrayPrefix sum+1	No attempts yet	1s	512 MB	Judgeable
Contemporary ArtGiven a square image's area a, output the perimeter of its square frame: 4 times the square root of a.	Easy2	Math	No attempts yet	1s	512 MB	Judgeable