[Swift] 백준! 2161번 - 카드1

https://www.acmicpc.net/problem/2161

2161번: 카드1

import Foundation

public struct Queue<T> {
  fileprivate var array = [T]()
  
  public var isEmpty: Bool {
    return array.isEmpty
  }
  
  public var count: Int {
    return array.count
  }
  
  public mutating func enquque(_ element: T) {
    array.append(element)
  }
  
  public mutating func dequeue() -> T? {
    if isEmpty {
      return nil
    } else {
      return array.removeFirst()
    }
  }
  
  public var front: T? {
    return array.first
  }
}

var queue = Queue<Int>()
let n = Int(readLine()!)!
for i in 1...n {
    queue.enquque(i)
}
var result:[Int] = []
while queue.count > 1 {
    result.append(queue.dequeue()!)
    queue.enquque(queue.dequeue()!)
}
result.append(queue.dequeue()!)

var str = ""
for n in result {
    str += "\(n) "
}
str.removeLast()
print(str)