import std.conv, std.stdio;
import std.algorithm, std.array, std.range, std.string;
void main()
{
    immutable k = readln.chomp.to!size_t;
    auto s = readln.chomp;
    if (k < s.length)
        return "%s...".writefln(s[0..k]);
    else
        return s.writeln;
}
