#!/usr/bin/env python

"""AtCoder Beginner Contest 168: B - 

https://atcoder.jp/contests/abc168/tasks/abc168_b

"""



__author__ = 'bugttle <bugttle@gmail.com>'





def main():

    K = int(eval(input()))

    S = eval(input())



    if len(S) <= K:

        print(S)

    else:

        print(("{}...".format(S[0:K])))



if __name__ == '__main__':

    main()

#!/usr/bin/env python

"""AtCoder Beginner Contest 168: B - ... (Triple Dots)

https://atcoder.jp/contests/abc168/tasks/abc168_b

"""





def main():

    K = int(eval(input()))

    S = eval(input())



    if len(S) <= K:

        print(S)

    else:

        print(("{}...".format(S[0:K])))





if __name__ == '__main__':

    main()

#!/usr/bin/env python
"""AtCoder Beginner Contest 168: B - 
https://atcoder.jp/contests/abc168/tasks/abc168_b
"""
__author__ = "bugttle <bugttle@gmail.com>"


def main():
    K = int(eval(input()))
    S = eval(input())
    if len(S) <= K:
        print(S)
    else:
        print(("{}...".format(S[0:K])))


if __name__ == "__main__":
    main()

#!/usr/bin/env python
"""AtCoder Beginner Contest 168: B - ... (Triple Dots)
https://atcoder.jp/contests/abc168/tasks/abc168_b
"""


def main():
    K = int(eval(input()))
    S = eval(input())
    if len(S) <= K:
        print(S)
    else:
        print(("{}...".format(S[0:K])))


if __name__ == "__main__":
    main()

-"""AtCoder Beginner Contest 168: B - +"""AtCoder Beginner Contest 168: B - ... (Triple Dots) -__author__ = "bugttle <bugttle@gmail.com>"