#####   ######  #####    ###    #   #  ###  #   #  ######
##  ##  ##      ##  ##  ## ##   #   #   #   #   #  ##
#####   ####    #####   #   #   #   #   #   #   #  ####
##  #   ##      ##      ## ##    # #    #    # #   ##
##   #  ######  ##       ###      #    ###    #    ######

$ curl repovive.com/roadmaps/google-interview-prep-v2/coding-patterns-i-arrays-strings-hash-maps/lc-482-license-key-formatting-implementation

░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░█████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████████

#####   ######  #####    ###    #   #  ###  #   #  ######
##  ##  ##      ##  ##  ## ##   #   #   #   #   #  ##
#####   ####    #####   #   #   #   #   #   #   #  ####
##  #   ##      ##      ## ##    # #    #    # #   ##
##   #  ######  ##       ###      #    ###    #    ######

$ curl repovive.com/roadmaps/google-interview-prep-v2/coding-patterns-i-arrays-strings-hash-maps/lc-482-license-key-formatting-implementation

Repovive

LeetCode 482 License Key Formatting - Implementation - Coding Patterns I: Arrays, Strings & Hash Maps | Google Interview Prep | Repovive

Repovive.

Google Interview Prep6 sections · 128 units7h total

Open in Course

LeetCode 482 License Key Formatting - Implementation

The code

Remove dashes, uppercase, then build groups from left to right. The first group gets the leftover characters.

function licenseKeyFormatting(s, k):
    cleaned = s.replace("-", "").toUpperCase()
    n = len(cleaned)
    if n == 0:
        return ""
    firstLen = n % k
    if firstLen == 0:
        firstLen = k
    result = cleaned[0:firstLen]
    i = firstLen
    while i < n:
        result += "-" + cleaned[i:i+k]
        i += k
    return result

$O(n)$ time, $O(n)$ space.