How to reverse array in Swift without using “.reverse()”?

Question

I have array and need to reverse it without Array.reverse method, only with a for loop.

var names:[String] = [\"Apple\", \"Microsof         


        

Answer 1

I like simple codes.

var names:[String] = ["Apple", "Microsoft", "Sony", "Lenovo", "Asus"]

var reversedNames = [""]

for name in names {
    reversedNames.insert(name, at: 0)
}

print(reversedNames)

Answer 2

Here is the most simpler way.

let names:[String] = ["Apple", "Microsoft", "Sony", "Lenovo", "Asus"]

var reversedNames = [String]()

for name in names {
    reversedNames.insert(name, at: 0)
}

Answer 3

func reverse(array: inout [String]) {
    if array.isEmpty { return }
    var f = array.startIndex
    var l = array.index(before: array.endIndex)
    while f < l {
        swap(array: &array, f, l)
        array.formIndex(after: &f)
        array.formIndex(before: &l)
    }
}

private func swap( array: inout [String], _ i: Int, _ j: Int) {
    guard i != j else { return }
    let tmp = array[i]
    array[i] = array[j]
    array[j] = tmp
}

Or you can write extension of course

Answer 4

Like this, maybe:

names = names.enumerate().map() { ($0.index, $0.element) }.sort() { $0.0 > $1.0 }.map() { $0.1 }

Oh, wait.. I have to use for loop, right? Then like this probably:

for (index, name) in names.enumerate().map({($0.index, $0.element)}).sort({$0.0 > $1.0}).map({$0.1}).enumerate() {
    names[index] = name
}

Answer 5

You can use the swift3 document:

let names = ["Chris", "Alex", "Ewa", "Barry", "Daniella"]
let reversedNames = names.sorted(by: >)

// reversedNames is equal to:
//   ["Ewa", "Daniella", "Chris", "Barry", "Alex"]

Answer 6

Here the code for swift 3

let array = ["IOS A", "IOS B", "IOS C"]
    for item in array.reversed() {
    print("Found \(item)")
    }