{
 "cells": [
  {
   "cell_type": "markdown",
   "source": [
    "You are given a license key represented as a string S which consists only\n",
    "alphanumeric character and dashes. The string is separated into N+1 groups by\n",
    "N dashes.\n",
    "\n",
    "Given a number K, we would want to reformat the strings such that each group\n",
    "contains _exactly_ K characters, except for the first group which could be\n",
    "shorter than K, but still must contain at least one character. Furthermore,\n",
    "there must be a dash inserted between two groups and all lowercase letters\n",
    "should be converted to uppercase.\n",
    "\n",
    "Given a non-empty string S and a number K, format the string according to the\n",
    "rules described above.\n",
    "\n",
    "**Example 1:**\n",
    "\n",
    "\n",
    "\n",
    "    Input: S = \"5F3Z-2e-9-w\", K = 4\n",
    "\n",
    "    Output: \"5F3Z-2E9W\"\n",
    "\n",
    "    Explanation: The string S has been split into two parts, each part has 4 characters.\n",
    "    Note that the two extra dashes are not needed and can be removed.\n",
    "\n",
    "\n",
    "**Example 2:**\n",
    "\n",
    "\n",
    "\n",
    "    Input: S = \"2-5g-3-J\", K = 2\n",
    "\n",
    "    Output: \"2-5G-3J\"\n",
    "\n",
    "    Explanation: The string S has been split into three parts, each part has 2 characters except the first part as it could be shorter as mentioned above.\n",
    "\n",
    "\n",
    "**Note:**\n",
    "\n",
    "  1. The length of string S will not exceed 12,000, and K is a positive integer.\n",
    "  2. String S consists only of alphanumerical characters (a-z and/or A-Z and/or 0-9) and dashes(-).\n",
    "  3. String S is non-empty."
   ],
   "metadata": {}
  },
  {
   "outputs": [
    {
     "output_type": "execute_result",
     "data": {
      "text/plain": "license_key_formatting (generic function with 1 method)"
     },
     "metadata": {},
     "execution_count": 1
    }
   ],
   "cell_type": "code",
   "source": [
    "# @lc code=start\n",
    "using LeetCode\n",
    "\n",
    "function license_key_formatting(S::String, K::Int)\n",
    "    res = \"\"\n",
    "    cnt = 0\n",
    "    for i in length(S):-1:1\n",
    "        if cnt == K\n",
    "            res *= '-'\n",
    "            cnt = 0\n",
    "        end\n",
    "        if S[i] != '-'\n",
    "            res *= uppercase(S[i])\n",
    "            cnt += 1\n",
    "        end\n",
    "    end\n",
    "    reverse(res)\n",
    "end\n",
    "# @lc code=end"
   ],
   "metadata": {},
   "execution_count": 1
  },
  {
   "cell_type": "markdown",
   "source": [
    "---\n",
    "\n",
    "*This notebook was generated using [Literate.jl](https://github.com/fredrikekre/Literate.jl).*"
   ],
   "metadata": {}
  }
 ],
 "nbformat_minor": 3,
 "metadata": {
  "language_info": {
   "file_extension": ".jl",
   "mimetype": "application/julia",
   "name": "julia",
   "version": "1.10.1"
  },
  "kernelspec": {
   "name": "julia-1.10",
   "display_name": "Julia 1.10.1",
   "language": "julia"
  }
 },
 "nbformat": 4
}