Problems

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Total results21,446 problems

Speed LimitEasy2
Implementation, Math +1No attempts yetTime limit5sMemory limit512 MB
Judgeable
Outer Triangle SumEasy2
Implementation, Array +2No attempts yetTime limit10sMemory limit512 MB
Judgeable
Linear EquationEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
X X gluedEasy2
String, Implementation +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Card Game ContestEasy2
Math, Implementation +2No attempts yetTime limit1sMemory limit256 MB
Judgeable
Perfect, deficient, or abundantEasy2
Math, Brute force +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
2017 Yonsei University Programming ContestEasy2
Brute force, Math +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Hongjun surrounded by fansEasy2
Implementation, StringNo attempts yetTime limit1sMemory limit64 MB
Judgeable
We Lost Again TodayEasy2
Implementation, Simulation +1No attempts yetTime limit1sMemory limit64 MB
Judgeable
2017 Ajou University Programming Contest (Small)Easy2
Sorting, ImplementationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
2017 Ajou Programming Contest (Large)Easy2
SortingNo attempts yetTime limit1sMemory limit512 MB
Judgeable
EmpathyEasy2
Math, String +2No attempts yetTime limit2sMemory limit256 MB
Judgeable
Jeonbuk National UniversityEasy2
Implementation, SimulationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Recovering a Damaged ISBN DigitEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit128 MB
Judgeable
I am happy~Easy2
Math, Implementation +2No attempts yetTime limit2sMemory limit256 MB
Judgeable
Fox SignEasy2
Implementation, ArrayNo attempts yetTime limit0.5sMemory limit512 MB
Judgeable
Who Is the Admin?Easy2
Implementation, Array +1No attempts yetTime limit1sMemory limit256 MB
Judgeable
Credit Card ValidationEasy2
Implementation, String +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Paint EstimateEasy2
Math, Implementation +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
Stacking CupsEasy2
Sorting, ImplementationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Advertising RevenueEasy2
Implementation, SimulationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Bedtime Reading IEasy2
Math, Number theory +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
UphillEasy2
Array, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Term index in an arithmetic sequenceEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Sharing apples and bananasEasy2
Math, Number theory +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Base converterEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Pepero Day 2017Easy2
ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Building a distribution tableEasy2
Implementation, Array +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
The 3n+1 SequenceEasy2
Simulation, Math +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Von Neumann and the FlyEasy2
Math, Implementation +2No attempts yetTime limit1sMemory limit512 MB
Judgeable
Soccer SkillsEasy2
Implementation, Geometry +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
I Work All DayEasy2
Implementation, Brute force +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Just A MinimEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Qualifiers for the Next PhaseEasy2
Sorting, Array +1No attempts yetTime limit1sMemory limit1024 MB
Judgeable
Coffee MachineEasy2
Brute force, Math +1No attempts yetTime limit1sMemory limit1024 MB
Judgeable
Happy TrailsEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Arggggggh!Easy2
Implementation, Math +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Life SavingsEasy2
Brute force, Math +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
Nine KnightsEasy2
Implementation, SimulationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Batter UpEasy2
Implementation, Math +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
No DuplicatesEasy2
String, Hash map +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Latin SquaresEasy2
Implementation, Array +2No attempts yetTime limit1sMemory limit512 MB
Judgeable
Congruent NumbersEasy2
Math, Number theory +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Boolean SatisfiabilityEasy2
Combinatorics, Math +2No attempts yetTime limit3sMemory limit512 MB
Judgeable
Atomic MassEasy2
String, Hash map +2No attempts yetTime limit1sMemory limit512 MB
Judgeable
Incomplete BookEasy2
Math, Simulation +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Analysis of Advanced AnalyticsEasy2
Simulation, Greedy +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Grass CuttingEasy2
Simulation, Implementation +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Jousting TournamentEasy2
Implementation, SimulationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Kiwis vs KangaroosEasy2
Implementation, String +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
Beautiful MusicEasy2
Implementation, String +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Letter CountEasy2
String, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Recently Used DocumentsEasy2
Simulation, Implementation +2No attempts yetTime limit1sMemory limit512 MB
Judgeable
PiratesEasy2
String, Hash map +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Password checkEasy2
String, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Opening CeremonyEasy2
Array, Implementation +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Triple JumpEasy2
Implementation, ArrayNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Hissing MicrophoneEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Sum Squared Digits FunctionEasy2
Math, Implementation +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Santa's GiftsEasy2
Math, Geometry +2No attempts yetTime limit5sMemory limit512 MB
Judgeable
Life ScoreEasy2
String, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Big number A+BEasy2
String, Math +2No attempts yetTime limit1sMemory limit256 MB
Judgeable
A Simple ProblemEasy2
Math, Implementation +1No attempts yetTime limit3sMemory limit512 MB
Judgeable
Check the CheckEasy2
Implementation, String +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Shattered CakeEasy2
Math, Implementation +2No attempts yetTime limit10sMemory limit512 MB
Judgeable
Triangles from Five SticksEasy2
Brute force, Geometry +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Jaccard Similarity ThresholdEasy2
Implementation, MathNo attempts yetTime limit1sMemory limit512 MB
Judgeable
PencilsEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Array Manipulation at Moloco (Easy)Easy2
Array, Brute forceNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Lorem ipsumEasy2
String, Implementation +1No attempts yetTime limit0.1sMemory limit512 MB
Judgeable
Hash collision stringsEasy2
String, Hash map +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
Abbey CourtyardEasy2
Math, Implementation +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Cube BitsEasy2
Math, ImplementationNo attempts yetTime limit4sMemory limit512 MB
Judgeable
Binary GameEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Sum of DivisorsEasy2
Math, Brute forceNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Lotto number frequencyEasy2
Implementation, ArrayNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Is N primeEasy2
Math, Number theory +1No attempts yetTime limit1sMemory limit256 MB
Judgeable
RickEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Midterm Exam GradingEasy2
Implementation, Array +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Exceed or notEasy2
Math, Implementation +1No attempts yetTime limit0.5sMemory limit128 MB
Judgeable
Derivative of a polynomial functionEasy2
String, Implementation +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Master Manager Nam JeonghunEasy2
Math, GreedyNo attempts yetTime limit1sMemory limit128 MB
Judgeable
Magic SquareEasy2
Implementation, Matrix +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
TeleportationEasy2
Math, Implementation +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
Jealous JinseoEasy2
Implementation, ArrayNo attempts yetTime limit1sMemory limit512 MB
Judgeable
PLAYERJINAH’S BOTTLEGROUNDSEasy2
Geometry, Math +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Master of the Shell GameEasy2
String, Simulation +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Overflow and ModuloEasy2
Math, Implementation +2No attempts yetTime limit1sMemory limit512 MB
Judgeable
What Is Your HandleEasy2
Sorting, String +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
It Worked, So Why Is It Wrong?Easy2
Implementation, Simulation +2No attempts yetTime limit1sMemory limit512 MB
Judgeable
HashingEasy2
Implementation, MathNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Matrix Multiplication CalculatorEasy2
Implementation, Matrix +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
Wak Sani SatayEasy2
Implementation, MathNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Caesar CipherEasy2
String, Implementation +1No attempts yetTime limit1sMemory limit64 MB
Judgeable
What Does UCPC Stand For?Easy2
String, Greedy +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Mannequins on the Tracks!!Easy2
Simulation, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Suchan Is a Marine Boy!!Easy2
Math, Implementation +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
Prize HunterEasy2
Implementation, ArrayNo attempts yetTime limit1sMemory limit512 MB
Judgeable
HappinessEasy2
Array, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Telemarketer or not?Easy2
Implementation, Brute forceNo attempts yetTime limit2sMemory limit512 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Speed LimitFor each log entry, multiply the speed by the time since the previous entry, sum these products, and print the total distance in miles.	Easy2	ImplementationMath+1	No attempts yet	5s	512 MB	Judgeable
Outer Triangle SumFor each triangle, add the first and last value of every row plus all values of the last row, counting shared corners once, and print the total.	Easy2	ImplementationArray+2	No attempts yet	10s	512 MB	Judgeable
Linear EquationFor each linear equation ax + b = c, decide whether it has no, one, or infinitely many solutions and print the root truncated to six decimals.	Easy2	MathImplementation	No attempts yet	2s	512 MB	Judgeable
X X gluedFor each registration number, print every run of two or more identical digits in the four-digit group, in left-to-right order.	Easy2	StringImplementation+1	No attempts yet	2s	512 MB	Judgeable
Card Game ContestFor each of N games, Meiji has A_i decks, or gets one basic deck if A_i is 0. Count the number of distinct ways to enter, modulo M.	Easy2	MathImplementation+2	No attempts yet	1s	256 MB	Judgeable
Perfect, deficient, or abundantFor each of T numbers below 10000, sum its proper divisors and classify it as Perfect, Deficient, or Abundant.	Easy2	MathBrute force+1	No attempts yet	1s	128 MB	Judgeable
2017 Yonsei University Programming ContestCount triples (A, B, C) with A+B+C = N, all at least 1, C at least B+2, and A even.	Easy2	Brute forceMath+1	No attempts yet	1s	128 MB	Judgeable
Hongjun surrounded by fansGiven Hongjun's id, print a 3 by 3 grid of emoticons with :id: in the center and :fan: in the other eight cells.	Easy2	ImplementationString	No attempts yet	1s	64 MB	Judgeable
We Lost Again TodayGiven the runs each team scored in all nine innings, decide whether the Ullim Geminis ever held a lead during a game they ended up losing.	Easy2	ImplementationSimulation+1	No attempts yet	1s	64 MB	Judgeable
2017 Ajou University Programming Contest (Small)Given up to three contestants' scores, submission counts, and last scoring upload times, output the number of the top-ranked contestant by the tie-break rules.	Easy2	SortingImplementation	No attempts yet	1s	512 MB	Judgeable
2017 Ajou Programming Contest (Large)Given each contestant's score, submission count, and last scoring upload time, print the number of the first-place contestant.	Easy2	Sorting	No attempts yet	1s	512 MB	Judgeable
EmpathyMultiply two binary numbers up to 30 bits long and print the product in binary without leading zeros.	Easy2	MathString+2	No attempts yet	2s	256 MB	Judgeable
Jeonbuk National UniversityPrint an ASCII symbol of width N when N is odd, following fixed spacing rules; print "I LOVE CBNU" when N is even.	Easy2	ImplementationSimulation	No attempts yet	1s	128 MB	Judgeable
Recovering a Damaged ISBN DigitOne digit of a 13-digit ISBN is replaced by '*', and you print the digit that makes the weighted checksum divisible by 10.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
I am happy~Given the height N, width M, and a seat number K in row-major order, print the row and column of that seat.	Easy2	MathImplementation+2	No attempts yet	2s	256 MB	Judgeable
Fox SignGiven up to 10 touching pairs among five fingers, decide whether the pattern matches the fox sign: thumb, middle, and ring all touch, while index and little touch nothing.	Easy2	ImplementationArray	No attempts yet	0.5s	512 MB	Judgeable
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