How to get the positions of an element in an array

Question

I have a question and I hope that one of you can help me: I need to find the positions of an element in an array. For example:

var elements: [String] = ["a","b","c","a","c"]
var element = "a"

I need to know in what positions is the element, in this case 0,3 I have tried with some nested for loops but it was a mess, can you help me? Thanks

https://stackoverflow.com/questions/24028860/how-to-find-index-of-list-item-in-swift may be a duplicate — Syed Mehtab Hassan, Mar 10 '19 at 16:51

score 0 · Accepted Answer · answered Mar 10 '19 at 16:53

0

Try this out:

var elements: [String] = ["a","b","c","a","c"]
var element = "a"
let indexes = elements.enumerated().compactMap { index, elem -> Int? in
  guard elem == element else { return nil }
  return index
}
print(indexes) // It will print [0, 3]

answered Mar 10 '19 at 16:53

alanpaivaa

1,959
1
14
23

The question is already closed as a duplicate. No need to post an answer. – rmaddy Mar 10 '19 at 16:57
@rmaddy I know that. I was writing it while you closed it and didn't notice. – alanpaivaa Mar 10 '19 at 16:58
1

@FrancescoMattiussi you can simply filter your collection indices `elements.indices.filter({elements[$0] == element})` – Leo Dabus Mar 10 '19 at 17:25

How to get the positions of an element in an array

1 Answers1