Look for coincidences in two arrays and create another one without the items that are repeated

Question

I am creating an app that gives rewards to the users, so they can obtain randomly complements to their avatars. I have a list of items that they can win and another list of items that they already have. My problem is that I don't know how to look for a match between the two arrays and create another without the ones that they already have.

var availableAvatar =['Csimple','Calien','Ccosmonaut','CgreenAereal','ChappyBirthday']
var userAvatars=['Ccosmonaut','ChappyBirthday']

I tried with the filter method but it creates an array of the matches and I don't know how to do it the other way. What I need:

var possibleAward=['Csimple','Calien','CgreenAereal']
var random = avatarP[Math.floor(Math.random() * possibleAward.length)];

Thank you very much.

https://stackoverflow.com/questions/1584370/how-to-merge-two-arrays-in-javascript-and-de-duplicate-items — chhil, Aug 09 '21 at 12:03
Does this answer your question? [Remove same Values from array of Object](https://stackoverflow.com/questions/60708097/remove-same-values-from-array-of-object) — Najam Us Saqib, Aug 10 '21 at 08:00

score 0 · Answer 1 · answered Aug 09 '21 at 12:02

var availableAvatar =['Csimple','Calien','Ccosmonaut','CgreenAereal','ChappyBirthday']
var userAvatars=['Ccosmonaut','ChappyBirthday']

var possibleRewards = availableAvatar.filter(element => {
  return !userAvatars.includes(element);
});

console.log(possibleRewards);

Robson · Accepted Answer · 2021-08-18T08:26:05.050

The array filter function is perfect for this:

var availableAvatars = ['Csimple','Calien','Ccosmonaut','CgreenAereal','ChappyBirthday']
var userAvatars = ['Ccosmonaut','ChappyBirthday']
var possibleAvatars = availableAvatars.filter(x => !userAvatars.includes(x));
var randomAvatar = possibleAvatars[Math.floor(Math.random() * possibleAvatars.length)];

console.log(possibleAvatars);
console.log(randomAvatar);

Look for coincidences in two arrays and create another one without the items that are repeated

2 Answers2