let K = Int(readLine()!)!
let S = readLine()!
let s: [Character] = S.map({$0})

if S.count > K {
    var text: String = ""
    for n in 0..<K {
        text.append(s[n])
    }
      text.append("...")
    print(text)
} else {
    print(S)
}
