OddOccurrencesInArray

public func solution(_ A : inout [Int]) -> Int {
    let removeDuplicate = NSCountedSet(array:A)
    var result: Int = 0
    for i in removeDuplicate {
        if removeDuplicate.count(for: i) == 1 {
            result = i as! Int
        }
    }
    return result
}

 

let removeDuplicate = NSCountedSet(array:A)

for i in removeDuplicate {
	removeDuplicate.count(for: i) == 1 

}

 

중복된 값이 1인것만 확인할수 있다.