[js: Number to Alphabet letters] #js

number2letters.js

/**
 * @link https://stackoverflow.com/a/64456745/11565411
 * @example
 *   numberToLetters(0) // A
 *   numberToLetters(1) // B
 *   numberToLetters(25) // Z
 *   numberToLetters(26) // AA
 *   numberToLetters(27) // AB
 *   numberToLetters(51) // AZ
 *   numberToLetters(52) // BA
 *   numberToLetters(701) // ZZ
 *   numberToLetters(702) // AAA
 */
export const numberToLetters = (num: number) => {
  let letters = ''

  while (num >= 0) {
    letters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'[num % 26] + letters
    num = Math.floor(num / 26) - 1
  }

  return letters
}