function groupByFirstLetter(words: string[]): Record<string, string[]> {
  if(words.length == 0) return {};
  const palabras: Record<string,string[]> = {};
  while (words.length != 0) {
    let ltemp = words[0].charAt(0).toLowerCase();
    let filtro = words.filter(a => a.charAt(0).toLowerCase() == ltemp.toLowerCase());
    palabras[ltemp] = filtro;
    words = words.filter(a => !filtro.includes(a));
  }
  return palabras;
}

// No modificar: necesario para evaluar el resultado.
export { groupByFirstLetter };