import std;

void main() {
    int k; scan(k);
    string s; scan(s);
    if (s.length > k) writeln(s[0..k], "...");
    else writeln(s);
}

void scan(T...)(ref T a) {
    string[] ss = readln.split;
    foreach (i, t; T) a[i] = ss[i].to!t;
}
T read(T=string)() { return readln.chomp.to!T; }
T[] reads(T)() { return readln.split.to!(T[]); }
alias readints = reads!int;
