export function decodeMessage(encoded: string, k: number): string {
  let ceil = Math.ceil(encoded.length / k);
  let result = "";

  function buildStr(index: number): string {
    if (index >= encoded.length) return ""
    return encoded[index] + buildStr(index + ceil)
  }

  for (let i = 0; i < ceil; i++) {
    result += buildStr(i)
  }

  return result.replace(" ","")
}