랜덤값을 중복되지 않게 추출

import UIKit var totalCount = 18 var gemCard = 1 var ranArray = [1,2,3,4,5,6,7,8,9,10,11,12,13] while(totalCount>0) {          let randomIndex = Int(arc4random_uniform(UInt32(ranArray.count)))     print(ranArray[randomIndex])          ranArray.remove(at: randomIndex)          totalCount-=2 }