import java.util.*

fun main(args: Array<String>) {
    val scan = Scanner(System.`in`)
    var k=scan.nextLine().toInt()
    var s =scan.nextLine()

    if(s.length>k)
    {
        var q = s.substring(0,k)
        println(q + "...")
    }
    else
        println(s)
}
