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Write a Swift program to change the first and last character of a given string.

This is an exercise for beginner I saw in w3resource. I found the solution isn’t work. It took me some time to figure out how it work. There is my solution:

func exchangeCh(_ typeWord:String)-> String{
    var str = typeWord
    // Get first and last character
    let firstCharacter = String(str.prefix(1))
    let LastCharacter = String(str.suffix(1))
    // Convert string to character
    let firstCharacter2 = Character(firstCharacter)
    let LastCharacter2 = Character(LastCharacter)
    // Remove first and last characters
    str.removeFirst()
    str.removeLast()
    // Insert first and last characters
    str.insert(LastCharacter2, at: (str.startIndex))
    str.insert(firstCharacter2, at: (str.endIndex))
    return str
}
print(exchangeCh(“Hello”))

And it could be simplified like this:

func exchangeCh(_ typeWord:String)-> String{
    var str = typeWord
    // Get first and last character
    let firstCharacter = String(str.prefix(1))
    let LastCharacter = String(str.suffix(1))
    // Remove first and last characters
    str.removeFirst()
    str.removeLast()
    return LastCharacter + str + firstCharacter
}
print(exchangeCh(“Hello”))