Problems

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Total results21,475 problems

Telemarketer or not?Easy2
Implementation, Brute forceNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Occupy ParkingEasy2
String, Implementation +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Are we there yet?Easy2
Array, Prefix sum +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
Income InequalityEasy2
Array, Implementation +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Larger Sport FacilityEasy2
Implementation, MathNo attempts yetTime limit2sMemory limit512 MB
Judgeable
What Is Today's Date?Easy2
ImplementationNo attempts yetTime limit2sMemory limit128 MB
Judgeable
Baby BitesEasy2
Implementation, StringNo attempts yetTime limit1sMemory limit512 MB
Judgeable
LukaEasy2
Implementation, SimulationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Pascal's TriangleEasy2
Math, Combinatorics +2No attempts yetTime limit1sMemory limit256 MB
Judgeable
Poker HandEasy2
Hash map, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
SculptureEasy2
Array, Implementation +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Setting a Time LimitEasy2
Math, Implementation +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Bessie and DaisyEasy2
Math, Geometry +1No attempts yetTime limit1sMemory limit128 MB
Judgeable
Unraveling Monty HallEasy2
Math, Simulation +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Tour de BINUSEasy2
Array, Prefix sum +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Contemporary ArtEasy2
MathNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Run-Length Encoding, Run!Easy2
String, SimulationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Pizza DealEasy2
Math, Geometry +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Mixing MilkEasy2
Simulation, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Winning ScoreEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Time to DecompressEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
ElderEasy2
Simulation, Implementation +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
ASCII ArtEasy2
Implementation, Math +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
ChessEasy2
Implementation, Math +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
Why Cherry Blossoms Bloomed on Info IslandEasy2
Brute force, Implementation +1No attempts yetTime limit2sMemory limit256 MB
Judgeable
Magnet ChainEasy2
Implementation, Brute force +2No attempts yetTime limit1sMemory limit256 MB
Judgeable
∑|ΔEasyMAX|Easy2
Prefix sum, Array +2No attempts yetTime limit1sMemory limit256 MB
Judgeable
Junseok's Math HomeworkEasy2
Math, ImplementationNo attempts yetTime limit0.5sMemory limit256 MB
Judgeable
Taxicab DistanceEasy2
Array, Implementation +2No attempts yetTime limit1sMemory limit256 MB
Judgeable
Physics HomeworkEasy2
Math, Implementation +2No attempts yetTime limit1sMemory limit256 MB
Judgeable
Card Factory (Small)Easy2
Implementation, MathNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Vending MachineEasy2
Implementation, Math +1No attempts yetTime limit1sMemory limit256 MB
Judgeable
XORChicEasy2
Implementation, Bit manipulation +2No attempts yetTime limit1sMemory limit256 MB
Judgeable
99 Bottles of BeerEasy2
Implementation, String +2No attempts yetTime limit1sMemory limit512 MB
Judgeable
Cute Number~ε٩(๑> ₃ <)۶зEasy2
Implementation, Math +2No attempts yetTime limit1sMemory limit512 MB
Judgeable
What's the Second Baseman's NameEasy2
Implementation, StringNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Wagle Wagle SoongkohanEasy2
Implementation, Array +2No attempts yetTime limit1sMemory limit512 MB
Judgeable
Bonus ScoreEasy2
Implementation, Simulation +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Buying SnacksEasy2
Implementation, Math +2No attempts yetTime limit1sMemory limit1024 MB
Judgeable
N! mod P (1)Easy2
Math, Implementation +2No attempts yetTime limit3sMemory limit1024 MB
Judgeable
What Is a Recursive Function?Easy2
Implementation, String +1No attempts yetTime limit1sMemory limit256 MB
Judgeable
BuffoonEasy2
Implementation, Array +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Hour for a RunEasy2
Math, Implementation +1No attempts yetTime limit0.5sMemory limit512 MB
Judgeable
Scores of Final ExaminationEasy2
Array, Implementation +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Missing NumbersEasy2
Array, Implementation +2No attempts yetTime limit1sMemory limit1024 MB
Judgeable
BagsEasy2
Hash map, Implementation +2No attempts yetTime limit1sMemory limit512 MB
Judgeable
369Easy2
Implementation, Math +2No attempts yetTime limit1sMemory limit512 MB
Judgeable
Mangling NamesEasy2
Implementation, String +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
TrolEasy2
Prefix sum, Math +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
What Is My Grade?Easy2
Array, Implementation +2No attempts yetTime limit1sMemory limit256 MB
Judgeable
CommandEasy2
String, Implementation +1No attempts yetTime limit0.5sMemory limit256 MB
Judgeable
This Problem’s a Slam DunkEasy2
Sorting, Array +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Simple Collatz SequenceEasy2
Simulation, Implementation +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Regional Team NamesEasy2
String, ImplementationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Piece of Cake!Easy2
Math, Implementation +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Mars WindowEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
Pea Soup and PancakesEasy2
Implementation, String +2No attempts yetTime limit1sMemory limit512 MB
Judgeable
License to LaunchEasy2
Array, Implementation +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
ÖstgötskaEasy2
String, Implementation +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Hanging Out on the TerraceEasy2
Simulation, ImplementationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
The Commuting GodEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
Even or Odd?Easy2
Math, Implementation +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Bullet SpeedEasy2
Math, ImplementationNo attempts yetTime limit0.5sMemory limit256 MB
Judgeable
Hot HikeEasy2
Brute force, Array +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Jazz EnthusiastEasy2
Math, Implementation +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Arithmetic MagicEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
TapiokaEasy2
String, ImplementationNo attempts yetTime limit2sMemory limit1024 MB
Judgeable
I'll Pay, No I'll PayEasy2
Simulation, Implementation +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Frozen Ticket BookingEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
TimeEasy2
Brute force, Implementation +2No attempts yetTime limit1sMemory limit256 MB
Judgeable
KBLTRNSEasy2
Implementation, Array +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
KABISAEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Lucky StraightEasy2
String, Implementation +2No attempts yetTime limit1sMemory limit256 MB
Judgeable
MergeEasy2
Two pointers, Implementation +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
The Nearest Value to XEasy2
Implementation, MathNo attempts yetTime limit2sMemory limit512 MB
Judgeable
CapitalizationEasy2
String, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Longest Ascending Contiguous SubsequenceEasy2
Array, Implementation +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
BananaEasy2
Hash map, String +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
Pokemon BuddyEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Card SwapEasy2
Hash map, Implementation +2No attempts yetTime limit0.3sMemory limit256 MB
Judgeable
A Problem for Testing a New Regrade MethodEasy2
Sorting, ImplementationNo attempts yetTime limit5sMemory limit512 MB
Judgeable
Divisionals SpellingEasy2
Implementation, String +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Odd vs. Even ShowdownEasy2
Math, Number theory +2No attempts yetTime limit1sMemory limit512 MB
Judgeable
Math Is an Online LectureEasy2
Math, ImplementationNo attempts yetTime limit1sMemory limit1024 MB
Judgeable
Frog 1Easy2
Math, ImplementationNo attempts yetTime limit1sMemory limit256 MB
Judgeable
ArtEasy2
Implementation, Math +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
ABCD CodeEasy2
Math, Implementation +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
Space PokerEasy2
Brute force, Math +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
RebusEasy2
String, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
The Pleasant WalkEasy2
Array, ImplementationNo attempts yetTime limit1sMemory limit512 MB
Judgeable
New Language CCEasy2
Bit manipulation, Math +1No attempts yetTime limit1sMemory limit512 MB
Judgeable
Chess PuzzleEasy2
Brute force, Implementation +2No attempts yetTime limit2sMemory limit512 MB
Judgeable
Santa ClausEasy2
Array, Implementation +1No attempts yetTime limit2sMemory limit512 MB
Judgeable
Stomping CatsEasy2
Array, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Long PythonEasy2
Math, ImplementationNo attempts yetTime limit2sMemory limit512 MB
Judgeable
Sator SquareEasy2
Implementation, Array +1No attempts yetTime limit1sMemory limit256 MB
Judgeable
Emergency MeetingEasy2
Implementation, Array +1No attempts yetTime limit1sMemory limit256 MB
Judgeable
Recommend the Next Morgorithm PresidentEasy2
Implementation, Sorting +1No attempts yetTime limit1sMemory limit1024 MB
Judgeable
Commemorative DiceEasy2
Brute force, Math +1No attempts yetTime limit0.5sMemory limit512 MB
Judgeable
Professor, your image is broken?Easy2
Implementation, Array +2No attempts yetTime limit1sMemory limit512 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
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
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
Run-Length Encoding, Run!Encode a string as run-length pairs, or decode run-length pairs back to the original string.	Easy2	StringSimulation	No attempts yet	2s	512 MB	Judgeable
Pizza DealCompare a slice's area per price with a whole pizza's pi*R1^2 per price and print the better deal.	Easy2	MathGeometry+1	No attempts yet	1s	512 MB	Judgeable
Mixing MilkSimulate 100 cyclic pours among three buckets, each pour moving as much milk as fits until the source empties or the target fills, and print the final amounts.	Easy2	SimulationImplementation	No attempts yet	2s	512 MB	Judgeable
Winning ScoreGiven the counts of 3-point shots, 2-point field goals, and free throws for two teams, compute each team's total and report which team won or if the game tied.	Easy2	MathImplementation	No attempts yet	1s	512 MB	Judgeable
Time to DecompressRead L lines, each with a count N and a character, and print that character repeated N times on its own line.	Easy2	StringImplementation	No attempts yet	1s	512 MB	Judgeable
ElderTrack which wizard owns the Elder Wand after each duel and count how many distinct wizards ever held it.	Easy2	SimulationImplementation+1	No attempts yet	1s	512 MB	Judgeable
ASCII ArtRead an N by M grid of RGB triples, apply the given intensity formula, map each value to a character via the threshold table, and print the grid.	Easy2	ImplementationMath+1	No attempts yet	1s	512 MB	Judgeable
ChessGiven one square in letter-number notation and another in a 1-to-64 numbering, decide whether the two squares share the same color on a chessboard.	Easy2	ImplementationMath+2	No attempts yet	2s	512 MB	Judgeable
Why Cherry Blossoms Bloomed on Info IslandSplit a sequence of N numbers into four consecutive nonempty groups, maximizing the sum of the four group products.	Easy2	Brute forceImplementation+1	No attempts yet	2s	256 MB	Judgeable
Magnet ChainGiven up to 5 magnets as a 1/2 sequence, decide whether the chain is fully connected after at most one magnet flip.	Easy2	ImplementationBrute force+2	No attempts yet	1s	256 MB	Judgeable
∑\|ΔEasyMAX\|Given a sequence of tempos, answer queries that ask for the sum of absolute differences between consecutive values over a range.	Easy2	Prefix sumArray+2	No attempts yet	1s	256 MB	Judgeable
Junseok's Math HomeworkFor each query value N, sum every positive multiple of 3 or 7 that does not exceed N.	Easy2	MathImplementation	No attempts yet	0.5s	256 MB	Judgeable
Taxicab DistanceGiven an N by M grid of 0s and 1s with exactly two 1s, print the Manhattan distance between them.	Easy2	ArrayImplementation+2	No attempts yet	1s	256 MB	Judgeable
Physics HomeworkFor each test case, find the time at which car A, starting slower than car B and accelerating, reaches or passes car B's constant speed.	Easy2	MathImplementation+2	No attempts yet	1s	256 MB	Judgeable
Card Factory (Small)One card is flipped a number of times; report the side showing after all flip orders, where the visible side never changes.	Easy2	ImplementationMath	No attempts yet	1s	256 MB	Judgeable
Vending MachineGiven a sequence of vending machine button presses with fixed prices, subtract the total cost from 5000 won and print the change.	Easy2	ImplementationMath+1	No attempts yet	1s	256 MB	Judgeable
XORChicGiven an XOR-encrypted string whose first 8 characters decode to "CHICKENS", recover the key and output the original string.	Easy2	ImplementationBit manipulation+2	No attempts yet	1s	256 MB	Judgeable
99 Bottles of BeerGiven N, print the full lyrics of the N Bottles of Beer song, with correct singular and plural wording.	Easy2	ImplementationString+2	No attempts yet	1s	512 MB	Judgeable
Cute Number~ε٩(๑> ₃ <)۶зGiven an integer up to 10^18, check whether its digits form an arithmetic sequence with a constant difference, and print one of two fixed messages.	Easy2	ImplementationMath+2	No attempts yet	1s	512 MB	Judgeable
What's the Second Baseman's NameGiven up to 1000 player names, check whether any name equals the string anj and print one of two fixed messages.	Easy2	ImplementationString	No attempts yet	1s	512 MB	Judgeable
Wagle Wagle SoongkohanGiven three distinct participation values, print OK if their sum is 100 or more, otherwise print Soongsil, Korea, or Hanyang for the smallest.	Easy2	ImplementationArray+2	No attempts yet	1s	512 MB	Judgeable
Bonus ScoreGiven a string of O and X for N problems, compute the total score where problem i gives i points plus a running bonus that grows on each O and resets on each X.	Easy2	ImplementationSimulation+1	No attempts yet	1s	512 MB	Judgeable
Buying SnacksGiven price and weight for three snacks, print the name of the one whose 10-bag weight per discounted price is highest.	Easy2	ImplementationMath+2	No attempts yet	1s	1024 MB	Judgeable
N! mod P (1)Given N and a prime P larger than N, compute N! modulo P.	Easy2	MathImplementation+2	No attempts yet	3s	1024 MB	Judgeable
What Is a Recursive Function?Given N, print the chatbot message 'What is a recursive function?' repeated with nested quotation marks for N levels of recursion.	Easy2	ImplementationString+1	No attempts yet	1s	256 MB	Judgeable
BuffoonGiven N vote counts in registration order, output S if the first candidate has the unique most votes, otherwise N.	Easy2	ImplementationArray+1	No attempts yet	1s	512 MB	Judgeable
Hour for a RunGiven laps V and signs per lap N, print the ceiling of VNi/10 signs for i = 1 through 9.	Easy2	MathImplementation+1	No attempts yet	0.5s	512 MB	Judgeable
Scores of Final ExaminationGiven m subjects and n students, with each subject's scores listed in a row, find the maximum total score across students.	Easy2	ArrayImplementation+1	No attempts yet	2s	512 MB	Judgeable
Missing NumbersGiven an increasing list of distinct numbers a child recited, print every integer from 1 up to the last recited number that is missing, or print "good job" if none are.	Easy2	ArrayImplementation+2	No attempts yet	1s	1024 MB	Judgeable
BagsGiven n waste pieces with identifiers, find the minimum number of bags so that each bag holds pieces of only one identifier.	Easy2	Hash mapImplementation+2	No attempts yet	1s	512 MB	Judgeable
369Count the total claps in the 369 game from 1 to N, where each number contributes one clap per digit that is 3, 6, or 9.	Easy2	ImplementationMath+2	No attempts yet	1s	512 MB	Judgeable
Mangling NamesGiven a table of pronunciation times by vowel and consonant counts, sum the times for each student name and report the total.	Easy2	ImplementationString+2	No attempts yet	2s	512 MB	Judgeable
TrolGiven an array where A[i] is the digital root of i for i from 1 to 260, answer Q queries asking for the sum over a range [l, r].	Easy2	Prefix sumMath+1	No attempts yet	1s	512 MB	Judgeable
What Is My Grade?Given 50 distinct scores sorted in descending order and Hongik's score, print the letter grade matching his rank using the fixed cutoffs.	Easy2	ArrayImplementation+2	No attempts yet	1s	256 MB	Judgeable
CommandFor each of T strings, decide whether it has length 7 and its characters follow the exact pattern AABBABB with exactly two distinct letters.	Easy2	StringImplementation+1	No attempts yet	0.5s	256 MB	Judgeable
This Problem’s a Slam DunkGiven the heights of five players on each of two teams, count how many State U players are taller than the opponent they guard after sorting both teams by height.	Easy2	SortingArray+1	No attempts yet	1s	512 MB	Judgeable
Simple Collatz SequenceSimulate the modified Collatz rule (halve even k, increment odd k) from n until reaching 1 and count the steps taken.	Easy2	SimulationImplementation+1	No attempts yet	1s	512 MB	Judgeable
Regional Team NamesDecide whether a string splits into an institution part of 2 to 8 characters, a hyphen, then a team name of 1 to 24 characters.	Easy2	StringImplementation	No attempts yet	1s	512 MB	Judgeable
Piece of Cake!Given a square cake of side n and thickness 4, two cuts at distances h and v from the top and left, find the largest piece's volume.	Easy2	MathImplementation+1	No attempts yet	1s	512 MB	Judgeable
Mars WindowGiven a year between 2018 and 10000, decide whether a launch window occurs in it, where windows are 26 months apart starting April 2018.	Easy2	MathImplementation	No attempts yet	1s	512 MB	Judgeable
Pea Soup and PancakesRead each restaurant's name and menu, then print the first one serving both pea soup and pancakes, or a fixed fallback line if none does.	Easy2	ImplementationString+2	No attempts yet	1s	512 MB	Judgeable
License to LaunchFind the earliest index of the minimum value in an array of n space-junk counts and print the zero-based day.	Easy2	ArrayImplementation+1	No attempts yet	1s	512 MB	Judgeable
ÖstgötskaCount how many space-separated words contain the substring "ae"; if that count is at least 40 percent of the words, print one fixed phrase, otherwise the other.	Easy2	StringImplementation+1	No attempts yet	1s	512 MB	Judgeable
Hanging Out on the TerraceTrack how many people are on a terrace with a limit L and count how many enter groups are turned away because they would exceed it.	Easy2	SimulationImplementation	No attempts yet	1s	512 MB	Judgeable
The Commuting GodGiven integers A and B where x^2 + 2Ax + B = 0 has integer roots, print the distinct roots in ascending order.	Easy2	MathImplementation	No attempts yet	1s	256 MB	Judgeable
Even or Odd?Given n, decide whether the sum of any n consecutive positive integers is always even, always odd, or depends on the starting point.	Easy2	MathImplementation+1	No attempts yet	1s	512 MB	Judgeable
Bullet SpeedGiven Cheolsu's running speed A and the bullet's speed B relative to him, print the bullet's speed toward the target, which is A + B.	Easy2	MathImplementation	No attempts yet	0.5s	256 MB	Judgeable
Hot HikePick a start day for a 3-day trip so the maximum temperature on the first and third days is as low as possible, breaking ties by smallest start day.	Easy2	Brute forceArray+1	No attempts yet	2s	512 MB	Judgeable
Jazz EnthusiastAdd up the lengths of n songs, subtract the crossfade time once for each pair of adjacent songs, and print the total as hh:mm:ss.	Easy2	MathImplementation+1	No attempts yet	2s	512 MB	Judgeable
Arithmetic MagicGiven N, compute (x+1)(y+1) - x - y - xy for chosen numbers x and y, which simplifies to 1, and raise it to N.	Easy2	MathImplementation	No attempts yet	2s	512 MB	Judgeable
TapiokaGiven a three-word dish name, remove the words "bubble" and "tapioka", then print the remaining words or "nothing" if none remain.	Easy2	StringImplementation	No attempts yet	2s	1024 MB	Judgeable
I'll Pay, No I'll PayPeople take turns adding to their outstretched amount; find who first reaches the threshold K and on which of their turns.	Easy2	SimulationImplementation+1	No attempts yet	2s	512 MB	Judgeable
Frozen Ticket BookingGiven a theater with N rows and M seats per row numbered row by row, print the seat number of the fourth seat of row L, or -1 if row L has no fourth seat.	Easy2	MathImplementation	No attempts yet	1s	512 MB	Judgeable
TimeCount how many clock times from 00:00:00 through N:59:59 contain the digit K at least once.	Easy2	Brute forceImplementation+2	No attempts yet	1s	256 MB	Judgeable
KBLTRNSGiven several routes, each with a time and a price, print the smallest time among the routes that reach the destination within the 12 hour limit.	Easy2	ImplementationArray+1	No attempts yet	2s	512 MB	Judgeable
KABISAGiven a list of years separated by commas, print the leap years among them, separated by spaces.	Easy2	MathImplementation	No attempts yet	2s	512 MB	Judgeable
Lucky StraightGiven an even-length number, decide whether the sum of its left-half digits equals the sum of its right-half digits, printing LUCKY or READY.	Easy2	StringImplementation+2	No attempts yet	1s	256 MB	Judgeable
MergeMerge two sorted sequences into one sorted sequence using the given tie-breaking rule, which takes from A when the front elements are equal.	Easy2	Two pointersImplementation+2	No attempts yet	2s	512 MB	Judgeable
The Nearest Value to XGiven X, L, and R, print the integer in [L, R] whose absolute difference from X is smallest.	Easy2	ImplementationMath	No attempts yet	2s	512 MB	Judgeable
CapitalizationReplace every occurrence of the substring "joi" in a lowercase string with "JOI" and print the result.	Easy2	StringImplementation	No attempts yet	2s	512 MB	Judgeable
Longest Ascending Contiguous SubsequenceGiven a sequence of positive integers, find the length of the longest contiguous run whose elements are non-decreasing.	Easy2	ArrayImplementation+1	No attempts yet	2s	512 MB	Judgeable
BananaRead a dictionary mapping English words to Minionese words, then translate each of T sentences word by word.	Easy2	Hash mapString+2	No attempts yet	2s	512 MB	Judgeable
Pokemon BuddyGiven a Pokemon group with a fixed distance per candy and starting and required candy counts, find the total kilometers to walk.	Easy2	MathImplementation	No attempts yet	2s	512 MB	Judgeable
Card SwapGiven two multisets of n cards, each a color letter plus a digit, decide whether they are identical or differ in at least one card.	Easy2	Hash mapImplementation+2	No attempts yet	0.3s	256 MB	Judgeable
A Problem for Testing a New Regrade MethodRead two integers A and B, print their sum, then read N numbers and print them sorted in ascending order.	Easy2	SortingImplementation	No attempts yet	5s	512 MB	Judgeable
Divisionals SpellingGiven n words and a contest with m questions labeled A onward, count how many words use only distinct letters from the first m letters.	Easy2	ImplementationString+1	No attempts yet	1s	512 MB	Judgeable
Odd vs. Even ShowdownGiven n, count how many numbers from 1 to n have an odd number of prime factors (with multiplicity) and compare against the rest.	Easy2	MathNumber theory+2	No attempts yet	1s	512 MB	Judgeable
Math Is an Online LectureGiven six integers defining two linear equations in two unknowns, solve the system and print the integer values of x and y.	Easy2	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Frog 1Given target coordinates and a jump count, decide whether a frog starting at the origin can reach that cell in exactly that many unit grid jumps.	Easy2	MathImplementation	No attempts yet	1s	256 MB	Judgeable
ArtGiven N paint drop coordinates, find the smallest axis-aligned rectangle that strictly contains every point, and print its bottom-left and top-right corners.	Easy2	ImplementationMath+2	No attempts yet	2s	512 MB	Judgeable
ABCD CodeFor each four-digit code, check whether the square of its first two digits plus the square of its last two digits leaves remainder 1 modulo 7.	Easy2	MathImplementation+2	No attempts yet	2s	512 MB	Judgeable
Space PokerGiven fixed counts of red, green, and blue chips and two coefficients, pick which single chip color to add to maximize a quadratic payout formula.	Easy2	Brute forceMath+2	No attempts yet	2s	512 MB	Judgeable
RebusSplit the input into space-separated words, strip leading and trailing apostrophes by removing that many letters from each end, then concatenate the pieces.	Easy2	StringImplementation	No attempts yet	2s	512 MB	Judgeable
The Pleasant WalkGiven a sequence of house colors, find the length of the longest contiguous segment in which no two adjacent houses share the same color.	Easy2	ArrayImplementation	No attempts yet	1s	512 MB	Judgeable
New Language CCGiven an integer n, print how many bits CC needs to store it after dropping leading zeros, with 0 stored in 1 bit.	Easy2	Bit manipulationMath+1	No attempts yet	1s	512 MB	Judgeable
Chess PuzzleGiven a knight's square on an 8x8 board, place a rook and a bishop so each attacks the knight, they do not attack each other, and the knight attacks neither.	Easy2	Brute forceImplementation+2	No attempts yet	2s	512 MB	Judgeable
Santa ClausGiven two lists of children who already have presents, output the children from 1 to n who are missing from both lists.	Easy2	ArrayImplementation+1	No attempts yet	2s	512 MB	Judgeable
Stomping CatsGiven cat counts per apartment in an n by m building, sum the fine a for every apartment whose upstairs neighbor has more than twice its cats.	Easy2	ArrayImplementation	No attempts yet	2s	512 MB	Judgeable
Long PythonGiven that a Python holds n whole Parrots or m whole Monkeys, find the minimum and maximum number of whole Parrots that fit into one Monkey.	Easy2	MathImplementation	No attempts yet	2s	512 MB	Judgeable
Sator SquareGiven an N by N grid of letters, check whether it reads the same horizontally and vertically, printing YES or NO.	Easy2	ImplementationArray+1	No attempts yet	1s	256 MB	Judgeable
Emergency MeetingGiven each player's vote or skip, find the player with the most votes, ejecting nobody on a tie.	Easy2	ImplementationArray+1	No attempts yet	1s	256 MB	Judgeable
Recommend the Next Morgorithm PresidentGiven N distinct names with scores, print the name with the highest score, breaking ties by lexicographically smallest name.	Easy2	ImplementationSorting+1	No attempts yet	1s	1024 MB	Judgeable
Commemorative DiceGiven two six-sided dice whose faces sum to 21, count the pairs where the first player's roll beats the second's and print the winning probability as a reduced fraction.	Easy2	Brute forceMath+1	No attempts yet	0.5s	512 MB	Judgeable
Professor, your image is broken?Given an N by N binary bitmap and a factor K, print the image with every pixel repeated K times in both directions.	Easy2	ImplementationArray+2	No attempts yet	1s	512 MB	Judgeable