min() and max() function

Don't use min and max for this.

For instance, create a func to test validity:

Code Block 
func isValidNumberOfPlayers(_ nb: Int) -> Bool {
  return nb > 0 && nb <= 10
}

Then, when you create or read the list of players, for instance in an array with their names:

Code Block 
var players: [String] = [] // You populate the array somewhere

In the func where you declare the players, check the value, call

Code Block 
if !isValidNumberOfPlayers(players.count) {
	print("number of players is not correct")
	// And do whatever you need to do
}

If you want to give a more precise test result, you could do this:

Code Block 
enum PlayersCheckState {
     case ok
     case null
     case tooMany
}
func isValidNumberOfPlayers(_ nb: Int) -> PlayersCheckState {
    switch nb {
    case ...0  : return .null
    case 1...10: return .ok
    default    : return .tooMany
    }
}

Then call

Code Block 
    switch isValidNumberOfPlayers(playersCount) {
    case .null : print("No player")
    case .tooMany: print("too many players")
    case .ok: break    //  do whatever you need to do here
    }

Thank you !

Thanks for feed back.

Don't forget to close the thread by marking the correct answer.

Good continuation.