Strings and text

Parsing, matching, and tries

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Still being built. Things may change

Total results3,614 problems

driip
Easy1
String, Implementation
No attempts yet
Time limit
0.5s
Memory limit
16 MB
Judgeable
Complex String
Easy1
String, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Next Character
Easy1
String, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Sports Day
Easy1
Implementation, String+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Canadians, eh?
Easy1
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
SciComLove (2022)
Easy1
String, Math
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Culture shock
Easy1
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Terraforming
Easy1
Implementation, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Seongtaek's Secret Password
Easy1
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
MBTI
Easy1
Implementation, String
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Sharing Birthdays
Easy1
Hash map, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Lowercase Specific Uppercase Letters
Easy1
String, Hash map
No attempts yet
Time limit
0.1s
Memory limit
512 MB
Judgeable
Chronogram
Easy1
Implementation, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Desni klik
Easy1
Implementation, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Decoder
Easy1
String, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Mutint
Easy1
Implementation, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Periods
Easy1
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Counting points
Easy1
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
The Missing Letter
Easy1
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Match Score
Easy1
String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Socks
Easy1
String, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
H4x0r
Easy1
Implementation, String
No attempts yet
Time limit
10s
Memory limit
1024 MB
Judgeable
Message Decowding
Easy1
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Krunch
Easy1
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Sasha and Zeros
Easy1
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Emoji Input Difficulty
Easy1
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Repeating String
Easy1
String, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Last Letter
Easy1
String, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
CodeMaster 2023
Easy1
Implementation, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Style change
Easy1
String, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Domino
Easy1
Implementation, String
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Results Table
Easy1
Implementation, String
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Logins
Easy1
String, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Welcome to SMUPC!
Easy1
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
2033 Meme Vote
Easy1
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Finding DKSH
Easy1
String, String matching
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Flipping letters
Easy1
Implementation, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Malvika is peculiar about balloon colors
Easy1
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Lucky 7
Easy1
Math, String+1
No attempts yet
Time limit
5s
Memory limit
1024 MB
Judgeable
Kick
Easy1
String, String matching
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Guan Gong, Why Did Only Your Head Arrive?
Easy1
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Since attending Seoul Cyber University
Easy1
String, Hash map
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Astrology
Easy1
Implementation, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Is Y a Vowel?
Easy1
String, Implementation
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Elice Track Matching
Easy1
Implementation, String
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Hamming Distance
Easy1
String, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Stroke Count
Easy1
String, Simulation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Matched Letters
Easy1
String, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Sticky Keys
Easy1
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Retaking a Course
Easy1
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Odd Even Game
Easy1
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Barcode Nickname
Easy1
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Build the String
Easy1
String, String matching
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Wow and Queries
Easy1
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Love is Korea University
Easy1
Implementation, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Just Round Down
Easy1
String, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Gahee and the Sub-station Name
Easy1
String
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Intuitive Elements
Easy1
String, Hash map
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Application List
Easy1
String, Implementation
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Oh Right, Garlic
Easy1
Hash map, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
OIJ
Easy1
String, Simulation
No attempts yet
Time limit
2s
Memory limit
2048 MB
Judgeable
Command Prompt
Easy2
String, Implementation
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Word Count
Easy2
String, Implementation
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Most Frequent Letter
Easy2
Hash map, String+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Basketball Game
Easy2
Hash map, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Word Sorting
Easy2
Sorting, String
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Octal to Binary
Easy2
String, Implementation+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Splitting a Word
Easy2
String, Brute force+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
House Number Sign
Easy2
Implementation, String+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Choosing a Team Name
Easy2
String, Implementation+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Group Word Checker
Easy2
String, Implementation
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Yujin Number
Easy2
String, Brute force+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Most Frequent Letters
Easy2
Hash map, String+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Sort Digits Descending
Easy2
Sorting, String+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Octopus Numbers
Easy2
String, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Good License Plates
Easy2
String, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Making Anagrams
Easy2
Hash map, String
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Prime Word
Easy2
String, Math+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Dobby's Case-Insensitive Word Test
Easy2
String, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Longest Digit Run
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Coin Game
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cryptoquote
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Binary Addition
Easy2
String, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Base Conversion
Easy2
Math, Implementation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Difference Between 5 and 6
Easy2
String, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Why Is KMP Called KMP?
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Changyeong's Diary
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Answer Pattern Guessing
Easy2
Simulation, String+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Octal
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Changyeong Village Cup Shuffle
Easy2
Simulation, String
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
Making an Acronym
Easy2
String, Implementation
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
Celebrity Jeopardy
Easy2
String, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Anagram Distance
Easy2
Hash map, String+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Numbersrebmun
Easy2
String, Two pointers+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
Keyboard Shifted One Key Right
Easy2
Hash map, String+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
driipGiven a lowercase string, print "cute" if it ends with the suffix "driip", otherwise print "not cute".	Easy1	StringImplementation	No attempts yet	0.5s	16 MB	Judgeable
Complex StringGiven a string of length N over the letters A through E, decide whether at least 3 distinct characters appear.	Easy1	StringImplementation	No attempts yet	2s	1024 MB	Judgeable
Next CharacterFor each position from 2 to N, print the previous character if the current character is J, one per line.	Easy1	StringImplementation	No attempts yet	2s	1024 MB	Judgeable
Sports DayGiven N students, K on the Red Team, and a string listing the other N-1 students' teams, decide Aoi's team.	Easy1	ImplementationString+2	No attempts yet	2s	1024 MB	Judgeable
Canadians, eh?Given one line of text, decide whether it ends with the exact string eh? and print Canadian! or Imposter!.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
SciComLove (2022)Given N up to 10^9, print the string SciComLove after moving its first character to the end N times.	Easy1	StringMath	No attempts yet	1s	256 MB	Judgeable
Culture shockCount how many words in a sentence are he, him, she, or her, given N words on one line.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
TerraformingAdds up Mars oxygen, ocean, and temperature changes from a list and checks whether oxygen reaches 14%, oceans reach 9%, and temperature reaches +8 C.	Easy1	ImplementationString	No attempts yet	1s	1024 MB	Judgeable
Seongtaek's Secret PasswordGiven N strings, the task is to print yes for each string whose length is between 6 and 9 characters, otherwise no.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
MBTIGiven Jinho's MBTI type and N friends' types, count how many friends share Jinho's type.	Easy1	ImplementationString	No attempts yet	1s	512 MB	Judgeable
Sharing BirthdaysGiven n birthdays written as mm/dd, count how many distinct dates appear, with duplicates counted once.	Easy1	Hash mapString	No attempts yet	1s	1024 MB	Judgeable
Lowercase Specific Uppercase LettersGiven a string A and a list B of uppercase letters, lowercase every occurrence of each letter in B within A and print the result.	Easy1	StringHash map	No attempts yet	0.1s	512 MB	Judgeable
ChronogramGiven text lines, sum the Roman numeral letter values (I, V, X, L, C, D, M) in each line and output the total as the year.	Easy1	ImplementationString	No attempts yet	1s	1024 MB	Judgeable
Desni klikFor each matrix, read the value of each column from the position of its single # and print the difference between the maximum and minimum values.	Easy1	ImplementationString	No attempts yet	1s	1024 MB	Judgeable
DecoderEach vowel in the encrypted text is shifted back one place in the cycle a, e, i, o, u, y, and the decoded lines are printed.	Easy1	StringSimulation	No attempts yet	1s	1024 MB	Judgeable
MutintGiven several positive integers ending with a zero, change each number's leftmost largest digit: odd digits become 0, and even digits gain 4 (mod 10).	Easy1	ImplementationString	No attempts yet	1s	1024 MB	Judgeable
PeriodsEach input line is a sentence, and the task adds a period to any line that lacks one.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Counting pointsGiven a string of n test results (T or N), count the groups of n/10 consecutive tests where every test is solved, and print that count.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
The Missing LetterGiven 25 distinct uppercase English letters, print the one letter of the alphabet that is missing.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Match ScoreCount how many A and B characters are in a goal record string and print the score as X : Y.	Easy1	String	No attempts yet	1s	1024 MB	Judgeable
SocksGiven a string of B and C socks, count how many same-color pairs of socks can be formed.	Easy1	StringImplementation	No attempts yet	2s	1024 MB	Judgeable
H4x0rReplaces the letters a, e, i, o, and s in a lowercase string with the digits 4, 3, 1, 0, and 5 and prints the result.	Easy1	ImplementationString	No attempts yet	10s	1024 MB	Judgeable
Message DecowdingDecode a message by mapping each letter through a 26-character substitution key, keeping case and spaces.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
KrunchGiven one sentence, remove all vowels from every word and print the sentence, dropping words that become empty.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Sasha and ZerosGiven k, count the zeros in k's decimal form that are not trailing zeros.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Emoji Input DifficultyGiven an emoji name like :chino_shock:, compute its input difficulty: its length plus the colon count plus 5 times the underscore count.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Repeating StringGiven a string of length N, the task is to check whether its first half equals its second half and print Yes or No.	Easy1	StringImplementation	No attempts yet	2s	1024 MB	Judgeable
Last LetterGiven a string S, print the result of removing its last character if that character is G, or appending G to the end otherwise.	Easy1	StringImplementation	No attempts yet	2s	1024 MB	Judgeable
CodeMaster 2023Read one of four chants and print its matching cheer from a fixed lookup, such as SONGDO mapping to HIGHSCHOOL.	Easy1	ImplementationString	No attempts yet	1s	1024 MB	Judgeable
Style changeConvert each camelCase or CamelCase variable name to snake_case by lowercasing all letters and inserting an underscore before each capital letter.	Easy1	StringImplementation	No attempts yet	2s	1024 MB	Judgeable
DominoGiven two domino tiles, the task is to decide whether they share a half with the same number of dots.	Easy1	ImplementationString	No attempts yet	2s	1024 MB	Judgeable
Results TableCount the rows of a results table that contain at least one '+' character, which marks a solved problem.	Easy1	ImplementationString	No attempts yet	2s	1024 MB	Judgeable
LoginsCheck whether a login of up to 10 characters starts with "io" and is followed by at least one digit.	Easy1	StringImplementation	No attempts yet	2s	1024 MB	Judgeable
Welcome to SMUPC!Given N, print the N-th letter of the repeating string WelcomeToSMUPC, which has length 14.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
2033 Meme VoteGiven N lines, print Yes if any line is not one of Rick Astley's seven original promises (case-sensitive), otherwise print No.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Finding DKSHCount the occurrences of the substring DKSH in a string of at most 1,000 characters made of D, K, S, and H.	Easy1	StringString matching	No attempts yet	1s	1024 MB	Judgeable
Flipping lettersGiven an N by N grid of d, b, q, and p, print the grid after flipping every letter vertically or horizontally.	Easy1	ImplementationString	No attempts yet	1s	1024 MB	Judgeable
Malvika is peculiar about balloon colorsGiven a string of 'a' and 'b' characters, find the fewest characters to flip so that all characters match.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Lucky 7Given an integer, the task is to print 0, 1, 2, or 3 depending on whether the number contains digit 7 and whether it is divisible by 7.	Easy1	MathString+1	No attempts yet	5s	1024 MB	Judgeable
KickCount the occurrences of the substring kick in a lowercase string of up to 5 million characters, including overlapping matches.	Easy1	StringString matching	No attempts yet	3s	1024 MB	Judgeable
Guan Gong, Why Did Only Your Head Arrive?Given N suspect names, print the one name that contains the letter S. Exactly one name has it.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Since attending Seoul Cyber UniversityGiven a lowercase string with spaces, commas, and periods, the task counts how often the most frequent letter appears.	Easy1	StringHash map	No attempts yet	1s	512 MB	Judgeable
AstrologyGiven a date as YYYY-MM-DD, print the zodiac sign of the Sun on that date using a fixed table of day ranges.	Easy1	ImplementationString	No attempts yet	1s	1024 MB	Judgeable
Is Y a Vowel?Given a lowercase word, count its vowels twice: once without counting y and once counting y as a vowel.	Easy1	StringImplementation	No attempts yet	1s	2048 MB	Judgeable
Elice Track MatchingGiven the track each of N friends applies to and Hellobit's track, count how many friends chose the same track as Hellobit.	Easy1	ImplementationString	No attempts yet	2s	1024 MB	Judgeable
Hamming DistanceGiven two equal-length strings, count the positions where their characters differ.	Easy1	StringImplementation	No attempts yet	2s	1024 MB	Judgeable
Stroke CountGiven a string of j, o, and i, the task is to sum their stroke counts (2, 1, and 2).	Easy1	StringSimulation	No attempts yet	2s	1024 MB	Judgeable
Matched LettersGiven a string, the task is to check whether every character is the same letter and print Yes or No.	Easy1	StringImplementation	No attempts yet	2s	1024 MB	Judgeable
Sticky KeysGiven a line of letters, digits, and spaces, collapse each run of identical consecutive characters into a single character and print the result.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Retaking a CourseGiven a course code and a list of course codes, count how many share the same first 5 characters as the given code.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Odd Even GameCount the even and odd digits of a given N-digit number K and print 0 if evens are more, 1 if odds are more, or -1 if they are equal.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Barcode NicknameGiven a string of only 'l' and 'I', the task is to flip the case of each character and print the result.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Build the StringGiven a string of length N up to 10, the task is to check whether the substring gori appears in it and print YES or NO.	Easy1	StringString matching	No attempts yet	1s	1024 MB	Judgeable
Wow and QueriesGiven Q strings made of W and O, count how many times the substring WOW appears in each one.	Easy1	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Love is Korea UniversityGiven N from 1 to 10, print the string LoveisKoreaUniversity N times on one line, separated by spaces.	Easy1	ImplementationString	No attempts yet	1s	1024 MB	Judgeable
Just Round DownGiven a positive decimal number as text, print its floor, the greatest integer not exceeding it.	Easy1	StringImplementation	No attempts yet	2s	1024 MB	Judgeable
Gahee and the Sub-station NameGiven one line with a station name and an optional sub-station name in parentheses, print the station name and the sub-station name, or '-' if there is none.	Easy1	String	No attempts yet	1s	512 MB	Judgeable
Intuitive ElementsGiven two lowercase strings, the task checks whether every letter in the abbreviation b also appears somewhere in the name a, printing YES or NO for each test case.	Easy1	StringHash map	No attempts yet	1s	2048 MB	Judgeable
Application ListGiven up to 100 lowercase program names, print a 5-row grid showing which letters a to z start at least one name, with dots for missing letters.	Easy1	StringImplementation	No attempts yet	2s	2048 MB	Judgeable
Oh Right, GarlicGiven the full list of N ingredients and N-1 used ones, the task is to print the single ingredient that is missing from the second list.	Easy1	Hash mapString	No attempts yet	1s	1024 MB	Judgeable
OIJGiven a string of J, O, and I, shift each letter forward in the cycle J to O, O to I, I to J and print the result.	Easy1	StringSimulation	No attempts yet	2s	2048 MB	Judgeable
Command PromptGiven N equal-length file names, output a pattern where each position is the common character if all names agree there, or a question mark otherwise.	Easy2	StringImplementation	No attempts yet	2s	128 MB	Judgeable
Word CountCount the number of space-separated words in a string that may have leading or trailing spaces.	Easy2	StringImplementation	No attempts yet	2s	128 MB	Judgeable
Most Frequent LetterCount letter frequencies in a string, case-insensitively, and print the most common letter in uppercase or a question mark on ties.	Easy2	Hash mapString+1	No attempts yet	2s	128 MB	Judgeable
Basketball GameGiven N surnames, count first letters and print all letters (in order) that start at least five surnames, or PREDAJA if none does.	Easy2	Hash mapImplementation+1	No attempts yet	1s	128 MB	Judgeable
Word SortingDeduplicate a list of words and sort them first by length, then lexicographically.	Easy2	SortingString	No attempts yet	2s	256 MB	Judgeable
Octal to BinaryConvert a huge octal number (up to 333,334 digits) into its binary representation without leading zeros.	Easy2	StringImplementation+1	No attempts yet	1s	256 MB	Judgeable
Splitting a WordSplit a lowercase word into three nonempty parts, reverse each part, and find the lexicographically smallest concatenation among all splits.	Easy2	StringBrute force+1	No attempts yet	2s	128 MB	Judgeable
House Number SignCompute the total width of a house-number sign given fixed per-digit widths and 1 cm margins between digits and at both ends, for each input number until 0 appears.	Easy2	ImplementationString+1	No attempts yet	1s	128 MB	Judgeable
Choosing a Team NameCount letters L,O,V,E across a fixed name plus each candidate string, compute a formula mod 100, and print the candidate with the highest value, breaking ties by lexicographic order.	Easy2	StringImplementation+1	No attempts yet	2s	128 MB	Judgeable
Group Word CheckerCount how many of up to 100 lowercase words have every repeated character forming a single contiguous block.	Easy2	StringImplementation	No attempts yet	2s	128 MB	Judgeable
Yujin NumberGiven an integer up to about 2.1 billion, determine whether some split of its digits into a left and right part yields equal digit products.	Easy2	StringBrute force+1	No attempts yet	2s	128 MB	Judgeable
Most Frequent LettersCount lowercase letter frequencies across up to 50 lines of text and print all letters tied for the highest frequency in alphabetical order.	Easy2	Hash mapString+1	No attempts yet	2s	128 MB	Judgeable
Sort Digits DescendingRearrange the digits of a given natural number so they appear in descending order and print the result.	Easy2	SortingString+1	No attempts yet	2s	128 MB	Judgeable
Octopus NumbersConvert base-8 strings using nine special symbols (including one for digit -1) into their decimal integer values until a terminator line appears.	Easy2	StringMath+1	No attempts yet	1s	128 MB	Judgeable
Good License PlatesFor each license plate, compute a base-26 value from the three letters and compare it to the four-digit number, printing whether their difference is within 100.	Easy2	StringImplementation+1	No attempts yet	1s	128 MB	Judgeable
Making AnagramsGiven two lowercase words, compute how many letters must be deleted in total so their remaining letters match as multisets (anagrams).	Easy2	Hash mapString	No attempts yet	2s	128 MB	Judgeable
Prime WordSum letter values (a-z=1-26, A-Z=27-52) for a word and print whether the sum is prime (with 1 counted as prime).	Easy2	StringMath+1	No attempts yet	2s	128 MB	Judgeable
Dobby's Case-Insensitive Word TestFor each test case, output the original-cased word that is smallest in dictionary order when comparisons ignore letter case.	Easy2	StringSorting+1	No attempts yet	1s	128 MB	Judgeable
Longest Digit RunFor three given eight-digit numbers, print the length of the longest run of identical consecutive digits in each.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Coin GameCount occurrences of each of 8 possible length-3 head/tail patterns among all consecutive triples in a 40-character coin toss string, for multiple test cases.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
CryptoquoteDecode each ciphertext message by substituting letters using a given 26-letter mapping while preserving spaces.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Binary AdditionAdd two binary strings up to length 80 for multiple test cases and print the sum without leading zeros.	Easy2	StringSimulation+1	No attempts yet	1s	128 MB	Judgeable
Base ConversionConvert a number given in an arbitrary base (2 to 36, using letters for digits above 9) into its decimal value.	Easy2	MathImplementation+1	No attempts yet	1s	128 MB	Judgeable
Difference Between 5 and 6Given two integers, compute the minimum and maximum possible sums after freely swapping digits 5 and 6 in each number.	Easy2	StringGreedy+1	No attempts yet	1s	128 MB	Judgeable
Why Is KMP Called KMP?Convert a hyphen-joined full name like Knuth-Morris-Pratt into its initials such as KMP.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Changyeong's DiaryDecode a string by replacing every vowel-p-vowel triple with the single vowel, restoring the original sentence.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Answer Pattern GuessingGiven an answer string, count matches against three fixed repeating guess patterns and report the highest score and who achieved it.	Easy2	SimulationString+1	No attempts yet	1s	128 MB	Judgeable
OctalConvert a binary string (up to 100 digits) to octal by padding and grouping bits in threes using the given table.	Easy2	StringImplementation	No attempts yet	1s	128 MB	Judgeable
Changyeong Village Cup ShuffleTrack the position of a ball among three cups after a sequence of swap operations described by characters A, B, C.	Easy2	SimulationString	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
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
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
Celebrity JeopardyGiven an equation of the form variable = value, output that same equation unchanged, preserving exact spacing.	Easy2	StringImplementation	No attempts yet	1s	128 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
NumbersrebmunMap each letter of a company name to its phone keypad digit, then check whether the resulting digit string reads the same forwards and backwards.	Easy2	StringTwo pointers+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
Keyboard Shifted One Key RightReplace every character of each input line with the key immediately to its left on a QWERTY keyboard, leaving spaces unchanged.	Easy2	Hash mapString+1	No attempts yet	1s	128 MB	Judgeable