how to randomize an array of strings?

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how to randomize an array of strings?

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I have an array and I want to randomize this array so that every time I start the app the elements are in a different position, how can I do this? I have found different extensions on the internet, and some work, but when doing it random, they repeat some pieces and they do not work or they do not work because I get this error.

Can not use mutating member on immutable value of type '[String]'

I have tried to solve this error, but what I find I can not understand why the error or how to solve it, I am a beginner in swift, I'm just working with Spritekit, I thought the error was because the array is in a struct, and I changed it to a class but it did not work, I'm using swift 4.1 I hope somebody could guide me on how to solve this problem I thank you from now:)

EDIT I have found the error of repeating elements, that array and properties I have in another class / struct and I need to accommodate the elements in a certain way once I put them in, I add them to the scene with a for and that for, I believe to call the class 25 times so that's why I repeat the elements, I hope I could have explained and hopefully now if you can help me :(

 for container in 0...24{

            self.addChild(containerSprite[container].block)

        }

ios swift spritekit

asked by Heber Solis 23.08.2018 в 05:19

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3 answers

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score 2 · Answer 1

the solution would be:

  var names = ["name1", "name2", "name3", "name4"];

  for index in names.indices {
   let number = arc4random_uniform(UInt32(names.count))
   names.swapAt(index.hashValue, Int(number))
  }

For iOS 12, or xcode 10, there will be a new function called shuffle (), which will randomize the arrays, I'll leave the link. link

That is, it would only be

var names = ["name1", "name2", "name3", "name4"];
names.shuffle()

score 0 · Answer 2

The solution I propose is the following:

You create an array that is initially empty.

You get the number of elements that the array has with all the Strings (array.count)

You make a loop until that number of elements is 0, and in each iteration of the loop:

You generate a random number between 0 and the number of elements -1
You remove the elements from the array with the Strings, insert it in the empty array and eliminate it from the initial one.
You subtract one from the number of elements that are in the initial array.

Sorry I can not send you the code, anyway, the solution is what matters:)

score 0 · Answer 3

One option can be:

func randomArray() {
    var randomValues: [String] = [String]()
    var copyContainers = containers

    for _ in 0..<containers.count {
        let random = copyContainers.randomElement()
        randomValues.append(random)
        copyContainers = copyContainers.filter{$0 != random}
    }

    print(randomValues)
}

extension Array {
    func randomElement() -> Element  {
        return self[Int(arc4random_uniform(UInt32(self.count)))]
    }
}