2908번 '상수'

if let input = readLine()?.split(separator: " ") {
    let a = input.first!
    let b = input.last!
    var realA: String = ""
    var realB: String = ""
    for i in 0..<a.count{
        realA.append(a[a.index(a.startIndex, offsetBy: a.count - i - 1)])
    }
    for i in 0..<b.count{
        realB.append(b[b.index(b.startIndex, offsetBy: b.count - i - 1)])
    }
    let realrealA = Int(realA)!
    let realrealB = Int(realB)!
    print(realrealA > realrealB ? realrealA : realrealB)
    
}