import java.util.*

fun main() {
    Scanner(System.`in`).use { scanner ->
        val k = scanner.nextInt()
        val s = scanner.next()
        val omitted = omitted(k, s)
        println(omitted)
    }
}

fun omitted(k: Int, s: String): String {
    if (s.length <= k) return s
    return s.slice(0 until k) + "..."
}