import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Scanner;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 *
 * @author Mehvix
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        abc168_b solver = new abc168_b();
        solver.solve(1, in, out);
        out.close();
    }

    static class abc168_b {
        public void solve(int testNumber, Scanner fin, PrintWriter fout) {
            int k = fin.nextInt();
            String s = fin.next();
            if (s.length() <= k) fout.println(s);
            else fout.println(s.substring(0, k) + "...");
        }

    }
}
 import java.io.OutputStream; OutputStream java.io import java.io.IOException; IOException java.io import java.io.InputStream; InputStream java.io import java.io.PrintWriter; PrintWriter java.io import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        abc168_b solver = new abc168_b();
        solver.solve(1, in, out);
        out.close();
    }

    static class abc168_b {
        public void solve(int testNumber, Scanner fin, PrintWriter fout) {
            int k = fin.nextInt();
            String s = fin.next();
            if (s.length() <= k) fout.println(s);
            else fout.println(s.substring(0, k) + "...");
        }

    }
} Main public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        abc168_b solver = new abc168_b();
        solver.solve(1, in, out);
        out.close();
    } main {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        abc168_b solver = new abc168_b();
        solver.solve(1, in, out);
        out.close();
    } InputStream inputStream = System.in; inputStream System.in System System.in OutputStream outputStream = System.out; outputStream System.out System System.out Scanner in = new Scanner(inputStream); in new Scanner(inputStream) PrintWriter out = new PrintWriter(outputStream); out new PrintWriter(outputStream) abc168_b solver = new abc168_b(); solver new abc168_b() solver.solve(1, in, out) solver.solve solver 1 in out out.close() out.close out String[] args args static class abc168_b {
        public void solve(int testNumber, Scanner fin, PrintWriter fout) {
            int k = fin.nextInt();
            String s = fin.next();
            if (s.length() <= k) fout.println(s);
            else fout.println(s.substring(0, k) + "...");
        }

    } abc168_b public void solve(int testNumber, Scanner fin, PrintWriter fout) {
            int k = fin.nextInt();
            String s = fin.next();
            if (s.length() <= k) fout.println(s);
            else fout.println(s.substring(0, k) + "...");
        } solve {
            int k = fin.nextInt();
            String s = fin.next();
            if (s.length() <= k) fout.println(s);
            else fout.println(s.substring(0, k) + "...");
        } int k = fin.nextInt(); k fin.nextInt() fin.nextInt fin String s = fin.next(); s fin.next() fin.next fin if (s.length() <= k) fout.println(s);
            else fout.println(s.substring(0, k) + "..."); s.length() <= k s.length() s.length s k fout.println(s) fout.println fout s fout.println(s.substring(0, k) + "...") fout.println fout s.substring(0, k) + "..." s.substring(0, k) s.substring s 0 k "..." int testNumber testNumber Scanner fin fin PrintWriter fout fout public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        abc168_b solver = new abc168_b();
        solver.solve(1, in, out);
        out.close();
    }

    static class abc168_b {
        public void solve(int testNumber, Scanner fin, PrintWriter fout) {
            int k = fin.nextInt();
            String s = fin.next();
            if (s.length() <= k) fout.println(s);
            else fout.println(s.substring(0, k) + "...");
        }

    }
} public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        abc168_b solver = new abc168_b();
        solver.solve(1, in, out);
        out.close();
    }

    static class abc168_b {
        public void solve(int testNumber, Scanner fin, PrintWriter fout) {
            int k = fin.nextInt();
            String s = fin.next();
            if (s.length() <= k) fout.println(s);
            else fout.println(s.substring(0, k) + "...");
        }

    }
} Main
import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Scanner;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 *
 * @author Mehvix
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        abc168_b solver = new abc168_b();
        solver.solve(1, in, out);
        out.close();
    }

    static class abc168_b {
        public void solve(int testNumber, Scanner fin, PrintWriter fout) {
            int k = fin.nextInt();
            String s = fin.next();
            if (s.length() <= k) fout.println(s);
            else fout.println(s.substring(0, k) + "...");
        }

    }
}

