Replace all 'A' present in an Array with '15' in Swift 3 - arrays

Question

I want to replace all A characters present in an array with 15 using Swift 3.
Example array:
["4", "5", "6", "A", "A", "Q", "A"]
Desired result:
["4", "5", "6", "15", "15", "Q", "15"]

Answer 1

map to the rescue:
var a = ["4", "5", "6", "A", "A", "Q", "A"]
a = a.map({ $0 == "A" ? "15" : $0 })
print(a)// ["4", "5", "6", "15", "15", "Q", "15"]
EDIT: After error screenshot:
You have an array of characters and hence the above code is not working. Also, remember "15" is two characters and not one character. Hence, I have replaced character 'A' with string "15" and mapped it to an array of strings, instead
let player1 = "456AAQA"
var player1Cards = Array(player1.characters) // ["4", "5", "6", "A", "A", "Q", "A"]
var player1CardsStrings = player1Cards.map{$0 == "A" ? "15" : String($0)}
player1CardsStrings // ["4", "5", "6", "15", "15", "Q", "15"]

Answer 2

Tested on Playground.
Because your question is lacking information that you didn't gave at first, here is what you can do.
"for loop": You iterate and replace the value if needed.
That's a logic you could apply on almost all languages.
var array1 = ["4", "5", "6", "A", "A", "Q", "A"]
for index in 0 ... array1.count-1
{
if array1[index] == "A"
{
array1[index] = "15"
}
}
print("array1: \(array1)")
"for each loop": You iterate and replace the value if needed.
That's a logic you could apply on almost all languages (maybe less languages that the previous one)
var array2 = ["4", "5", "6", "A", "A", "Q", "A"]
for (index, object) in array2.enumerated()
{
if object == "A"
{
array2[index] = "15"
}
}
print("array2: \(array2)")
"map": the "map" iterate for you (here is the important part behind the magic), you check the value and replace the value if needed. The $0 represent the "current item".
Here is a specificity.
var array3 = ["4", "5", "6", "A", "A", "Q", "A"]
array3 = array3.map({
if $0 == "A"
{
return "15"
}
return $0
})
print("array3: \(array3)")
"map": the "map" iterate for you, you check the value and replace the value if needed with a ternary if test.
var array4 = ["4", "5", "6", "A", "A", "Q", "A"]
array4 = array4.map({$0 == "A" ? "15" : $0})
print("array4: \(array4)")
I'm gave 4 ways (I've could also have explicit more the map() with explicit closure, from the simplest to the more complicated. We can't know if you don't show your attempts where you are are stucked. Is it for loop? The basic algorithms?
Swift advanced user may be more fond of the last one, but for beginners, it's quite complex and "magic". So when they want to change it a little for a different test, they never know what to do.
Side note: I'm not a Swift developer, more an Objective-C, so it may be lacking of checks. This answers is to show different approaches, how you go from a "verbose" to a less "verbose" code, but that you need to master anyway. Even if you have issue with map(), you can "bypass" it and do it manually.

Answer 3

let values = ["4", "5", "6", "A", "A", "Q", "A"]
let mappedvalues = values.map({ (value: String) -> String in
if value != "A" {
return value
}
return "15"
})