import java.util.*;
import java.util.zip.*;
import java.util.List;
import java.util.regex.*;
import java.util.concurrent.*;
import java.util.concurrent.atomic.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.text.*;
import javax.swing.table.*;
import java.io.*;
import java.net.*;
import java.lang.reflect.*;
import java.lang.ref.*;
import java.lang.management.*;
import java.security.*;
import java.security.spec.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import javax.imageio.*;
import java.math.*;
public class main {


public static void main(String[] args) throws Exception {
  List<String> emails = new ArrayList<String>();
  for (String line : toLinesFullTrim(new File(userHome(), "Documents/emails.txt")))
    addIfNotEmpty(emails, findEmailInLine(line));
  print(join(", ", emails));
}

static String findEmailInLine(String s) {
  Matcher m = Pattern.compile("\\S+@\\S+").matcher(s);
  return m.find() ? m.group() : null;
}
static String _userHome;
static String userHome() {
  if (_userHome == null) {
    if (isAndroid())
      _userHome = "/storage/sdcard0/";
    else
      _userHome = System.getProperty("user.home");
    //System.out.println("userHome: " + _userHome);
  }
  return _userHome;
}

static File userHome(String path) {
  return new File(userDir(), path);
}
static volatile StringBuffer local_log = new StringBuffer(); // not redirected
static volatile StringBuffer print_log = local_log; // might be redirected, e.g. to main bot

// in bytes - will cut to half that
static volatile int print_log_max = 1024*1024;
static volatile int local_log_max = 100*1024;

static boolean print_silent; // total mute if set

static void print() {
  print("");
}

// slightly overblown signature to return original object...
static <A> A print(A o) {
  if (print_silent) return o;
  String s = String.valueOf(o) + "\n";
  StringBuffer loc = local_log;
  StringBuffer buf = print_log;
  int loc_max = print_log_max;
  if (buf != loc && buf != null) {
    print_append(buf, s, print_log_max);
    loc_max = local_log_max;
  }
  if (loc != null) 
    print_append(loc, s, loc_max);
  System.out.print(s);
  return o;
}

static void print(long l) {
  print(String.valueOf(l));
}

static void print(char c) {
  print(String.valueOf(c));
}

static void print_append(StringBuffer buf, String s, int max) {
  synchronized(buf) {
    buf.append(s);
    max /= 2;
    if (buf.length() > max) try {
      int newLength = max/2;
      int ofs = buf.length()-newLength;
      String newString = buf.substring(ofs);
      buf.setLength(0);
      buf.append("[...] ").append(newString);
    } catch (Exception e) {
      buf.setLength(0);
    }
  }
}
static List<String> toLinesFullTrim(String s) {
  List<String> l = toLines(s);
  for (ListIterator<String> i = l.listIterator(); i.hasNext(); ) {
    String line = i.next().trim();
    if (line.length() == 0)
      i.remove();
    else
      i.set(line);
  }
  return l;
}

static List<String> toLinesFullTrim(File f) {
  return toLinesFullTrim(loadTextFile(f));
}

  public static String join(String glue, Iterable<String> strings) {
    StringBuilder buf = new StringBuilder();
    Iterator<String> i = strings.iterator();
    if (i.hasNext()) {
      buf.append(i.next());
      while (i.hasNext())
        buf.append(glue).append(i.next());
    }
    return buf.toString();
  }
  
  public static String join(String glue, String[] strings) {
    return join(glue, Arrays.asList(strings));
  }
  
  public static String join(Iterable<String> strings) {
    return join("", strings);
  }
  
  public static String join(String[] strings) {
    return join("", strings);
  }

static void addIfNotEmpty(List<String> l, String s) {
  if (nempty(s))
    l.add(s);
}


  public static String loadTextFile(String fileName) {
    try {
      return loadTextFile(fileName, null);
    } catch (IOException e) {
      throw new RuntimeException(e);
    }
  }
  
  public static String loadTextFile(String fileName, String defaultContents) throws IOException {
    if (!new File(fileName).exists())
      return defaultContents;

    FileInputStream fileInputStream = new FileInputStream(fileName);
    InputStreamReader inputStreamReader = new InputStreamReader(fileInputStream, "UTF-8");
    return loadTextFile(inputStreamReader);
  }
  
  public static String loadTextFile(File fileName) {
    try {
      return loadTextFile(fileName, null);
    } catch (IOException e) {
      throw new RuntimeException(e);
    }
  }

  public static String loadTextFile(File fileName, String defaultContents) throws IOException {
    try {
      return loadTextFile(fileName.getPath(), defaultContents);
    } catch (IOException e) {
      throw new RuntimeException(e);
    }
  }
  
  public static String loadTextFile(Reader reader) throws IOException {
    StringBuilder builder = new StringBuilder();
    try {
      char[] buffer = new char[1024];
      int n;
      while (-1 != (n = reader.read(buffer)))
        builder.append(buffer, 0, n);
        
    } finally {
      reader.close();
    }
    return builder.toString();
  }
static File userDir() {
  return new File(userHome());
}

static File userDir(String path) {
  return new File(userHome(), path);
}
static boolean nempty(Collection c) {
  return !isEmpty(c);
}

static boolean nempty(CharSequence s) {
  return !isEmpty(s);
}

static boolean nempty(Object[] o) {
  return !isEmpty(o);
}

static List<String> toLines(File f) {
  return toLines(loadTextFile(f));
}

  public static List<String> toLines(String s) {
    List<String> lines = new ArrayList<String>();
    if (s == null) return lines;
    int start = 0;
    while (true) {
      int i = toLines_nextLineBreak(s, start);
      if (i < 0) {
        if (s.length() > start) lines.add(s.substring(start));
        break;
      }

      lines.add(s.substring(start, i));
      if (s.charAt(i) == '\r' && i+1 < s.length() && s.charAt(i+1) == '\n')
        i += 2;
      else
        ++i;

      start = i;
    }
    return lines;
  }

  private static int toLines_nextLineBreak(String s, int start) {
    for (int i = start; i < s.length(); i++) {
      char c = s.charAt(i);
      if (c == '\r' || c == '\n')
        return i;
    }
    return -1;
  }
static boolean isAndroid() { return System.getProperty("java.vendor").toLowerCase().indexOf("android") >= 0; }


static boolean isEmpty(Collection c) {
  return c == null || c.isEmpty();
}

static boolean isEmpty(CharSequence s) {
  return s == null || s.length() == 0;
}

static boolean isEmpty(Object[] a) {
  return a == null || a.length == 0;
}

static boolean isEmpty(Map map) {
  return map == null || map.isEmpty();
}

}