FizzBuzz, precisely
Return a newline-separated string for 1..n: Fizz, Buzz, FizzBuzz, or the number.
Reverse a string
Return the characters of the string in reverse order.
Palindrome check
Return True if the string reads the same forwards and backwards (ignoring case and non-alphanumeric).
Count vowels
Count the number of vowels (a, e, i, o, u) in a string (case-insensitive).
Title case converter
Return the string with each word capitalised.
Anagram check
Return True if two strings are anagrams of each other.
Run-length encoding
Compress consecutive identical characters, e.g. 'aaabbc' → 'a3b2c1'.
Longest common prefix
Find the longest common prefix among a list of strings.
Integer to Roman
Convert a positive integer to its Roman numeral representation.
Zigzag string conversion
Encode a string in zigzag order across numRows rows, then read row by row.
Group anagrams
Group words that are anagrams of each other.
First non-repeating character
Find the index of the first character that appears only once.
Valid parentheses
Return True if brackets in the string close in the correct order.
Word ladder length
Return the length of the shortest transformation from beginWord to endWord changing one letter at a time.
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