#include <bits/stdc++.h>
using namespace std;
int main()
{    int k;
    cin>>k;
    string s;
    cin>>s;
    if(s.size()>k)
    {
        for(int i=0;i<k;i++){cout<<s[i];}
        cout<<"...";
    }
    else
    {
        cout<<s;
    }
}
    
