get-plural.ts

export default (num: number, one: string, few: string, many: string): string => {
  const n = Math.abs(num);

  if (n % 10 === 1 && n % 100 !== 11) {
    return one;
  }

  if (n % 10 >= 2 && n % 10 <= 4 && (n % 100 < 10 || n % 100 >= 20)) {
    return few;
  }

  return many;
};