makeArrayConsecutive scrimba coding challange

makeArrayConsecutive.js

// function makeArrayConsecutive returns the number of missing items between smallest 
// and largest number in provided array

const makeArrayConsecutive = function (array) {
  array.sort((a, b) => a - b);
  let myArray = [];
  for (i = array[0]; i < array[array.length - 1]; i++) {
    myArray.push(i);
  }
  myArray = myArray.filter(function (el) {
    return !array.includes(el);
  });
  return myArray.length;
};