Interview warm-up

Short whiteboard warmups

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Total results4,880 problems

Scanner
Easy2
Simulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Snow White and the Seven Dwarfs
Easy2
Brute force, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
15-Puzzle Displacement
Easy2
Array, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Find the Even Numbers
Easy2
Array, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Number Reversal
Easy2
String, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Scaled Chessboard
Easy2
Simulation, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Making an Acronym
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
BUHA
Easy2
Array, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Vigenère Cipher Encryption
Easy2
String, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Hamming Distance
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Binary Number
Easy2
Bit manipulation, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Hyunwoo the Professor
Easy2
Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Automated Telephone Exchange
Easy2
Brute force, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Electrification
Easy2
Simulation, Bit manipulation
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Flat
Easy2
Implementation, Math
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
K-Graph Oddity
Easy2
Graph, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Explicit Formula
Easy2
Bit manipulation, Implementation+1
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Cutting a Block
Easy2
Math, Simulation+1
No attempts yet
Time limit
2s
Memory limit
64 MB
Judgeable
Anagram Distance
Easy2
Hash map, String+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Minesweeper
Easy2
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Right Triangle
Easy2
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Logo
Easy2
Simulation, Geometry+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Prerequisites?
Easy2
Implementation, Hash map+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
AFC Wimbledon
Easy2
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Combination Lock
Easy2
Simulation, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Hay Points
Easy2
Hash map, String
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Babelfish
Easy2
Hash map, String+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Always Follow the Rules in Zombieland
Easy2
Array, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bubble Gum, Bubble Gum, in the Dish, How Many Pieces Do You Wish?
Easy2
Array, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Number Card Game
Easy2
Simulation, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Refrigerator Magnets
Easy2
Implementation, String+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Mirror Image
Easy2
String, Hash map+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Gnome Sequencing
Easy2
Implementation, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Parity
Easy2
String, Bit manipulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Quicksum
Easy2
String, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Doubles
Easy2
Array, Hash map+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Magnificent Meatballs
Easy2
Array, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Fifty Coats of Gray
Easy2
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Roaming Romans
Easy2
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Filling Out the Team
Easy2
Implementation, Brute force+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
General Chemistry Lab
Easy2
Implementation, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cantor Set
Easy2
Recursion, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Next Number
Easy2
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Number Guessing Game
Easy2
Implementation, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Judging Olympia
Easy2
Implementation, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
ICPC Score Totalizer Software
Easy2
Implementation, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Savings
Easy2
Simulation, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Ah!
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Death Knight Hero
Easy2
String, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Jean and Joe's Clothes
Easy2
Implementation, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
DVDs
Easy2
Implementation, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Oil Exploration
Easy2
Array, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Map Interface
Easy2
Array, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Isn't It Funny How a Bear Likes Honey?
Easy2
Math, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Contest Seats
Easy2
Implementation, Hash map+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Alphabet Distance
Easy2
String, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Vigenère Cipher
Easy2
String, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Stacked Floating Mountains
Easy2
Implementation, Array+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Chess Puzzle
Easy2
Implementation, Hash map+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Checkerboard Rows
Easy2
Array, Hash map+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Counting Swann's Coins
Easy2
Implementation, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Secret Location
Easy2
String, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Greatest Common Divisor
Easy2
Math, Number theory+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Dedupe
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Football Team
Easy2
String, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Garbled Message
Easy2
String, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Yoda
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Escape Route
Easy2
Brute force, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Total Count
Easy2
Hash map, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Target Practice
Easy2
Implementation, Simulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Annoying Mosquitos
Easy2
Brute force, Implementation+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
League
Easy2
Implementation, Array+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Dice Game
Easy2
Simulation, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Time Card
Easy2
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Change
Easy2
Greedy, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Caesar Cipher
Easy2
String, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Card Flipping Game
Easy2
Simulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tunnel Entrance and Exit
Easy2
Implementation, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Birthday
Easy2
Implementation, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Hailstone Sequences
Easy2
Simulation, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Factorial Base
Easy2
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Pangram
Easy2
String, Hash map+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Feynman
Easy2
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Head or Tail
Easy2
Implementation, Array+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Pascal Library
Easy2
Array, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Grade Statistics
Easy2
Sorting, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Roll-call in Woop Woop High
Easy2
Implementation, String+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Breed Proximity
Easy2
Array, Hash map+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Contest Timing
Easy2
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Odd or Even
Easy2
String, Math+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Barn Echoes
Easy2
String, Brute force+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Papaya Jungle
Easy2
Simulation, Array+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Scavenger Hunt
Easy2
Math, Brute force+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Hay Expenses
Easy2
Prefix sum, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Statistics
Easy2
Array, Sorting+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
TV Reports
Easy2
Implementation, Simulation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
IBM Minus One
Easy2
String, Implementation+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Color Me Less
Easy2
Implementation, Brute force+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Getting Chorded
Easy2
Implementation, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Deli Deli
Easy2
String, Hash map+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
ScannerExpand an R by C character grid by repeating each character ZR times vertically and ZC times horizontally, then print the result.	Easy2	SimulationImplementation+1	No attempts yet	1s	128 MB	Judgeable
Snow White and the Seven DwarfsGiven nine distinct numbers, find and print in increasing order the seven of them that sum to exactly 100.	Easy2	Brute forceArray	No attempts yet	1s	128 MB	Judgeable
15-Puzzle DisplacementCompute the total Manhattan distance of each labeled tile from its position in the solved 4x4 15-puzzle board.	Easy2	ArrayMath+1	No attempts yet	1s	128 MB	Judgeable
Find the Even NumbersFor each test case with seven numbers, output the sum and minimum of the even ones among them.	Easy2	ArrayImplementation	No attempts yet	1s	128 MB	Judgeable
Number ReversalFor each number, reverse its digits, add to the original, and print YES if the sum is a palindrome, else NO.	Easy2	StringMath+1	No attempts yet	1s	128 MB	Judgeable
Scaled ChessboardPrint a checkerboard of R by C cells where each cell is scaled to an A by B block of X or dot characters.	Easy2	SimulationImplementation	No attempts yet	1s	128 MB	Judgeable
Making an AcronymBuild an acronym from the first letters of words in a phrase, skipping a fixed list of filler words unless one is the first word.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
BUHAGiven up to 100 square bomb-range constraints on an A by B grid, count how many cells satisfy all the inside/outside conditions.	Easy2	ArraySimulation+1	No attempts yet	1s	128 MB	Judgeable
Vigenère Cipher EncryptionEncrypt repeated plaintext lines with a repeating key using a shifted Vigenère cipher until a line with 0 appears.	Easy2	StringSimulation+1	No attempts yet	1s	128 MB	Judgeable
Hamming DistanceFor each test case, count the positions where two equal-length binary strings differ and print the Hamming distance.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Binary NumberFor each given integer, output the positions of all bits set to 1 in its binary representation, from least to most significant.	Easy2	Bit manipulationImplementation	No attempts yet	1s	128 MB	Judgeable
Hyunwoo the ProfessorFor each given N, output the number of trailing zeros in N! by counting factors of 5.	Easy2	Math	No attempts yet	1s	128 MB	Judgeable
Automated Telephone ExchangeGiven a 3-digit exchange index n, count pairs of two-digit numbers a,b (00-99) such that n - a - b = 0.	Easy2	Brute forceMath	No attempts yet	1s	128 MB	Judgeable
ElectrificationGiven switch-to-lamp toggle mappings and a sequence of switch flips, compute and print the final on/off state of each lamp using parity counting.	Easy2	SimulationBit manipulation	No attempts yet	2s	256 MB	Judgeable
FlatGiven room areas and types, compute total area, total bedroom area, and flat cost using half-weighted balcony area.	Easy2	ImplementationMath	No attempts yet	3s	256 MB	Judgeable
K-Graph OddityCompute the maximum vertex degree in a graph and output the smallest odd integer greater than or equal to it.	Easy2	GraphImplementation+1	No attempts yet	1s	128 MB	Judgeable
Explicit FormulaGiven 10 binary inputs, evaluate a fixed XOR-of-ORs boolean formula (equivalently just count pairs/triplets with at least one 1 and check parity) and output the result.	Easy2	Bit manipulationImplementation+1	No attempts yet	3s	256 MB	Judgeable
Cutting a BlockGiven a box and n, print the coordinates of n equal slabs formed by evenly spaced cuts along the x-axis, each rounded to 8 decimals.	Easy2	MathSimulation+1	No attempts yet	2s	64 MB	Judgeable
Anagram DistanceGiven many word pairs, count letters to delete from both so their letter frequency histograms match, using character counts.	Easy2	Hash mapString+1	No attempts yet	1s	256 MB	Judgeable
MinesweeperGiven a grid of mines and empty cells, replace each empty cell with the count of mines in its eight neighbors.	Easy2	SimulationImplementation+2	No attempts yet	1s	128 MB	Judgeable
Right TriangleRead triples of side lengths until 0 0 0, and print right if the squares of the two shorter sides sum to the square of the longest, else wrong.	Easy2	MathImplementation+2	No attempts yet	1s	128 MB	Judgeable
LogoTrack a turtle's position and heading through forward, backward, left, and right commands, then report the rounded distance from the start.	Easy2	SimulationGeometry+2	No attempts yet	1s	128 MB	Judgeable
Prerequisites?Given Freddie's chosen courses and category minimums, check whether each category has at least the required number of his courses.	Easy2	ImplementationHash map+2	No attempts yet	1s	128 MB	Judgeable
AFC WimbledonGiven the sum and difference of two non-negative scores, print the larger score first, or -1 if no such scores exist.	Easy2	MathImplementation+1	No attempts yet	1s	128 MB	Judgeable
Combination LockGiven the dial position and three combination numbers, sum the degrees turned clockwise and counter-clockwise to open the lock.	Easy2	SimulationMath+1	No attempts yet	1s	128 MB	Judgeable
Hay PointsSum dictionary values of words appearing in each job description line block until a single period terminates it.	Easy2	Hash mapString	No attempts yet	1s	128 MB	Judgeable
BabelfishBuild a foreign-to-English word dictionary from the input, then translate each foreign word in the message, printing eh for unknown words.	Easy2	Hash mapString+1	No attempts yet	1s	128 MB	Judgeable
Always Follow the Rules in ZombielandRead q quotes in order, then answer r lookups by printing the quote at that 1-based index, or "No such rule" if out of range.	Easy2	ArrayImplementation+1	No attempts yet	1s	128 MB	Judgeable
Bubble Gum, Bubble Gum, in the Dish, How Many Pieces Do You Wish?Given a list of names arranged in a circle, a starting person, and a count n, find who is at position n in the count.	Easy2	ArraySimulation+1	No attempts yet	1s	128 MB	Judgeable
Number Card GameFor each starting number S, repeatedly replace it with the product of its digits until a single digit appears, printing every value in order.	Easy2	SimulationImplementation+2	No attempts yet	1s	128 MB	Judgeable
Refrigerator MagnetsRead lines until END and print each line that contains no repeated letter, ignoring spaces.	Easy2	ImplementationString+2	No attempts yet	1s	128 MB	Judgeable
Mirror ImageFor each word until the terminator '#', print the string reversed with each letter replaced by its mirror image, or INVALID if any letter lacks a mirror.	Easy2	StringHash map+1	No attempts yet	1s	128 MB	Judgeable
Gnome SequencingFor each of N triples of beard lengths, decide whether the three values are strictly increasing or strictly decreasing, then print Ordered or Unordered.	Easy2	ImplementationSorting+2	No attempts yet	1s	128 MB	Judgeable
ParityRead bit strings whose last bit is missing plus a parity letter, and append the 0 or 1 that makes the parity match.	Easy2	StringBit manipulation+1	No attempts yet	1s	128 MB	Judgeable
QuicksumCompute a weighted checksum for each input line: sum each character's 1-based position times its letter value, where spaces count as 0, until a line with only #.	Easy2	StringImplementation+2	No attempts yet	1s	128 MB	Judgeable
DoublesFor each list of 2 to 15 natural numbers ending in 0, count how many values x have 2x also in the same list.	Easy2	ArrayHash map+1	No attempts yet	1s	128 MB	Judgeable
Magnificent MeatballsGiven a circular list of guest meatball counts, find the position k where the sum of positions 1 through k equals the sum of the rest.	Easy2	ArrayPrefix sum+1	No attempts yet	1s	128 MB	Judgeable
Fifty Coats of GrayGiven room dimensions, opening sizes, and the area one can covers, compute the total paintable area for n apartments and round up to whole cans.	Easy2	MathImplementation+2	No attempts yet	1s	128 MB	Judgeable
Roaming RomansConvert each English-mile distance into Roman miles and paces using a fixed ratio, rounding the pace count to the nearest integer.	Easy2	MathImplementation+2	No attempts yet	1s	128 MB	Judgeable
Filling Out the TeamFor each player's speed, weight, and strength, print the positions whose limits the player satisfies, in table order, or No positions.	Easy2	ImplementationBrute force+1	No attempts yet	1s	128 MB	Judgeable
General Chemistry LabGiven a sequence of temperatures ending with 999, print each temperature's difference from the previous one, rounded to two decimals.	Easy2	ImplementationMath+1	No attempts yet	1s	128 MB	Judgeable
Cantor SetFor each N, print a line of 3^N characters following the Cantor set rule: each third-level block of size 3^k has its middle third blanked, dashes elsewhere.	Easy2	RecursionImplementation+2	No attempts yet	1s	128 MB	Judgeable
Next NumberGiven three distinct integers from an arithmetic or geometric progression, decide which type it is and print the label with the next term.	Easy2	MathImplementation+2	No attempts yet	1s	128 MB	Judgeable
Number Guessing GameFor each n0, report whether 3n0 is odd or even and print n4, the quotient of (n23)/9.	Easy2	ImplementationMath+1	No attempts yet	1s	128 MB	Judgeable
Judging OlympiaFor each line of six judge grades, discard the highest and lowest and print the average of the remaining four, stopping at the all-zero line.	Easy2	ImplementationMath+1	No attempts yet	1s	128 MB	Judgeable
ICPC Score Totalizer SoftwareFor each contestant, drop one highest and one lowest judge score, then output the truncated average of the rest.	Easy2	ImplementationSorting+2	No attempts yet	1s	128 MB	Judgeable
SavingsFor each test case, print how many years of multiplying the balance by (1 + B/100) are needed until it first exceeds M.	Easy2	SimulationMath+2	No attempts yet	1s	128 MB	Judgeable
Ah!Compare two strings of the form a...ah and print go if the first has at least as many a characters as the second.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Death Knight HeroCount how many of the given ability strings avoid the forbidden substring "CD".	Easy2	StringImplementation+1	No attempts yet	1s	128 MB	Judgeable
Jean and Joe's ClothesRead clothing sizes and count how many items go to Joe, Jean, Jane, James, or no one, per visit until N equals 0.	Easy2	ImplementationSimulation+2	No attempts yet	1s	128 MB	Judgeable
DVDsApply a series of clamped sale and restock transactions to each DVD title's stock and report the final count.	Easy2	ImplementationSimulation+2	No attempts yet	1s	128 MB	Judgeable
Oil ExplorationFor each column of a grid, scan downward and sum drilling costs (H costs 3, S costs 1) until the first oil cell, or print N if none exists.	Easy2	ArraySimulation+1	No attempts yet	1s	128 MB	Judgeable
Map InterfaceGiven station coordinates and a visited sequence, count how many stations fall inside the smallest axis-aligned rectangle covering the visited stations.	Easy2	ArrayImplementation+2	No attempts yet	1s	128 MB	Judgeable
Isn't It Funny How a Bear Likes Honey?Given Pooh's weight and the radii of several spherical helium balloons, decide whether their combined lift strictly exceeds his weight.	Easy2	MathImplementation+2	No attempts yet	1s	128 MB	Judgeable
Contest SeatsCount how many participants fail to get their chosen seat, since only the first arrival for a seat can sit there.	Easy2	ImplementationHash map+1	No attempts yet	1s	128 MB	Judgeable
Alphabet DistanceFor each test case, read two equal-length uppercase words and print the alphabet distance between the paired letters at every position.	Easy2	StringImplementation+1	No attempts yet	1s	128 MB	Judgeable
Vigenère CipherEncrypt each given plaintext with the Vigenère cipher, shifting every letter by the aligned repeated keyword letter modulo 26.	Easy2	StringImplementation+1	No attempts yet	1s	128 MB	Judgeable
Stacked Floating MountainsGiven several sequences, decide for each whether every element from the third onward equals the sum of the two before it.	Easy2	ImplementationArray+1	No attempts yet	1s	128 MB	Judgeable
Chess PuzzleFor each board, read the rook coordinates and report SAFE if no two rooks share a row or column, otherwise NOT SAFE.	Easy2	ImplementationHash map+2	No attempts yet	1s	128 MB	Judgeable
Checkerboard RowsFor each of B boards, read n pieces given as column-row pairs and print the largest number of pieces sharing the same row.	Easy2	ArrayHash map+1	No attempts yet	1s	128 MB	Judgeable
Counting Swann's CoinsPrint numbers 1 through N, replacing multiples of 3 with Dead, of 5 with Man, and of 15 with DeadMan, breaking the line after each word.	Easy2	ImplementationMath+1	No attempts yet	1s	128 MB	Judgeable
Secret LocationEach of six lines encodes one number by its character count; print the first three as Latitude and the last three as Longitude in the given format.	Easy2	StringImplementation+2	No attempts yet	1s	128 MB	Judgeable
Greatest Common DivisorRead n pairs of positive integers and print the greatest common divisor of each pair on its own line.	Easy2	MathNumber theory+1	No attempts yet	1s	128 MB	Judgeable
DedupeFor each of several strings, collapse every run of consecutive identical letters into a single letter and print the result.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Football TeamRead names one per line and swap every i with e and every I with E in each name.	Easy2	StringImplementation+1	No attempts yet	1s	128 MB	Judgeable
Garbled MessageRead lines of garbled text until EOF and replace every occurrence of the substring "iiing" with "th", preserving all other characters and line breaks.	Easy2	StringImplementation+1	No attempts yet	1s	128 MB	Judgeable
YodaFor each sentence, move its first two words to the end and print the result.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Escape RouteGiven your position and n-1 planet positions, find the closest planet, print both coordinates, and print the distance rounded to two decimals.	Easy2	Brute forceMath+1	No attempts yet	1s	128 MB	Judgeable
Total CountRead fighter names until a line with 0, print each name with its kill count in first-appearance order, then the grand total.	Easy2	Hash mapImplementation+2	No attempts yet	1s	128 MB	Judgeable
Target PracticePrint an n by n square border with an X drawn across the inner grid using asterisks.	Easy2	ImplementationSimulation	No attempts yet	1s	128 MB	Judgeable
Annoying MosquitosGiven up to 100 mosquito positions and up to 10000 swat centers, count how many mosquitos fall within the 101x101 square of at least one swat.	Easy2	Brute forceImplementation+1	No attempts yet	1s	256 MB	Judgeable
LeagueGiven every match result in a round-robin soccer league, compute each team's total points and print its rank, where tied teams share the best rank.	Easy2	ImplementationArray+2	No attempts yet	1s	128 MB	Judgeable
Dice GameSimulate a piece on a board of cells, applying a die roll then the cell's instruction, and report how many rolls reach the goal.	Easy2	SimulationArray	No attempts yet	1s	128 MB	Judgeable
Time CardGiven clock-in and clock-out times for three employees in h m s form, print each employee's working duration as hours, minutes, and seconds.	Easy2	MathImplementation+1	No attempts yet	1s	128 MB	Judgeable
ChangeGiven a purchase amount below 1000 yen paid with a 1000-yen bill, find the minimum number of coins in the change.	Easy2	GreedyMath+1	No attempts yet	1s	128 MB	Judgeable
Caesar CipherGiven an uppercase word encrypted by shifting each letter forward three positions, shift every letter back by three to recover the original.	Easy2	StringImplementation+2	No attempts yet	1s	128 MB	Judgeable
Card Flipping GameGiven two rows of n digit cards, reveal pairs left to right; the larger card wins both cards' sum, and equal cards each keep their own.	Easy2	SimulationImplementation+1	No attempts yet	1s	128 MB	Judgeable
Tunnel Entrance and ExitTrack the number of cars in a tunnel each minute from entrance and exit counts, and print the maximum count, or 0 if it ever goes negative.	Easy2	ImplementationSimulation+1	No attempts yet	1s	128 MB	Judgeable
BirthdayGiven each student's name and birthday, print the name of the youngest student, then the oldest.	Easy2	ImplementationSorting+1	No attempts yet	1s	128 MB	Judgeable
Hailstone SequencesFor each starting value H up to 500, simulate the Collatz rule and print the largest number that appears before reaching 1.	Easy2	SimulationImplementation+1	No attempts yet	1s	128 MB	Judgeable
Factorial BaseRead each factorial-base number, weight digit at position i (from the right, 1-indexed) by i!, and print the decimal value.	Easy2	MathImplementation+1	No attempts yet	1s	128 MB	Judgeable
PangramRead sentences until a line holding a single asterisk, and print Y if a sentence contains all 26 lowercase letters, otherwise N.	Easy2	StringHash map+1	No attempts yet	1s	128 MB	Judgeable
FeynmanFor each N, count all axis-aligned squares contained in an N by N grid of unit cells, ending at the sentinel 0.	Easy2	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Head or TailFor each test case, count the zeros and ones in the list of game results and print how many games Mary and John each won.	Easy2	ImplementationArray+1	No attempts yet	1s	128 MB	Judgeable
Pascal LibraryGiven D attendance rows over N alumni, decide whether some alumnus attended every dinner.	Easy2	ArrayImplementation+1	No attempts yet	1s	128 MB	Judgeable
Grade StatisticsFor each class, read the scores, then report the maximum, the minimum, and the largest gap between neighboring scores after sorting in descending order.	Easy2	SortingImplementation+1	No attempts yet	1s	128 MB	Judgeable
Roll-call in Woop Woop HighRead each class's answers and count pupils into four groups: correct first try, correct late, never correct, and absent.	Easy2	ImplementationString+1	No attempts yet	1s	128 MB	Judgeable
Breed ProximityGiven a line of N cows with breed ids, find the largest breed id whose two occurrences lie within K positions of each other, or -1 if none exist.	Easy2	ArrayHash map+1	No attempts yet	1s	128 MB	Judgeable
Contest TimingShe starts at 11:11 on 11/11. Given the day, hour, and minute she stops, print the minutes elapsed, or -1 if the stop is earlier.	Easy2	MathImplementation+1	No attempts yet	1s	128 MB	Judgeable
Odd or EvenRead N large integers up to 10^60 and print odd or even for each, judging parity from the last digit.	Easy2	StringMath+2	No attempts yet	1s	128 MB	Judgeable
Barn EchoesGiven two lowercase strings, find the length of the longest string that is a prefix of one and a suffix of the other.	Easy2	StringBrute force+2	No attempts yet	1s	128 MB	Judgeable
Papaya JungleBessie moves greedily through a grid, always stepping to the adjacent square with the most uneaten papayas, and we sum the fruit she eats until she reaches the bottom-right corner.	Easy2	SimulationArray+2	No attempts yet	1s	128 MB	Judgeable
Scavenger HuntList every pair (x, y) where x divides P and y divides Q, sorted by x then y.	Easy2	MathBrute force+1	No attempts yet	1s	128 MB	Judgeable
Hay ExpensesGiven N daily hay counts and Q ranges, output the sum of counts over each range from S to E inclusive.	Easy2	Prefix sumArray	No attempts yet	1s	128 MB	Judgeable
StatisticsRead N integers, print their mean and median rounded to six decimal places.	Easy2	ArraySorting+2	No attempts yet	1s	128 MB	Judgeable
TV ReportsTrack daily Dollar prices against the previous day and the running all-time high, printing NTV drop headlines and BBTV record headlines in day order.	Easy2	ImplementationSimulation+2	No attempts yet	1s	128 MB	Judgeable
IBM Minus OneFor each of n uppercase names, shift every letter to the next letter of the alphabet, wrapping Z to A, and print the result with numbered headers.	Easy2	StringImplementation+2	No attempts yet	1s	128 MB	Judgeable
Color Me LessRead 16 target RGB colors, then map each following color to the nearest target color by Euclidean distance, breaking ties by earliest appearance.	Easy2	ImplementationBrute force+2	No attempts yet	1s	128 MB	Judgeable
Getting ChordedGiven three note names, decide whether their semitone spacing forms a major or minor chord, then print the echo with the root-named chord or "unrecognized".	Easy2	ImplementationMath+1	No attempts yet	1s	128 MB	Judgeable
Deli DeliFor each of N words, apply the first matching pluralization rule from a list of irregular forms and four suffix rules, then print the result.	Easy2	StringHash map+2	No attempts yet	1s	128 MB	Judgeable