Coding Challenge

extension Int {
    func expressNumber() -> [Int] {
        var result: [Int] = []
        let stringNum = String(self)
        var count = stringNum.count - 1
        for x in stringNum {
            var element = String(x)
            let str = String(repeating: "0", count: count)
            element += str
            result.append(Int(element) ?? 0)
            count -= 1
        }
        return result
    }
}