text: 'use strict';
  function insertDash(num) {
    let stringify = String(num);
    let withDash = '';
     (let i = 0; i < stringify.length; i++) {
      withDash += stringify.charAt(i);
      if ((Number(stringify.charAt(i)) % 2 === 1) && (Number(stringify.charAt(i + 1)) % 2 === 1)) {
        withDash += '-';
      }
    }
    return withDash;
  }