export function groupAnagrams(words: string[]): string[][] {
  if (!words.length) return []

  const map = new Map<string, string[]>()

  for (const word of words) {
    const key = word.split('').sort().join('')

    if (!map.has(key)) {
      map.set(key, [])
    }

    map.get(key).push(word)
  }

  const result: string[][] = []
  
  for (const group of map.values()) {
    group.sort()
    result.push(group)
  }

  result.sort((a, b) => a[0].localeCompare(b[0]))

  return result;
}