Hotjar code sample

filter.js

function filterAndGroup(people){
  //Add empty object to offset it
  people.unshift({})
  //Use reduce method to loop through and sort
  return people.reduce((grouped,obj) => {
    //Gender of current item
    const gender = obj.gender;
    //Check age requirement
    if(obj.age >= 30 && obj.age <= 40)
    {
      //Append this perso to the accumulators array of this gender
      grouped[gender] = (grouped[gender] || []).concat(obj);
    }
    //return accumulator
    return grouped;
  })
}