Problem: You are given n words, each of which consists of lowercase alphabet letters. Each word contains at least one vowel. You are going to choose some of the given words and make as many beautiful lyrics as possible.

Each lyric consists of two lines. Each line consists of two words separated by whitespace. 

A lyric is beautiful if and only if it satisfies all conditions below. 

  * The number of vowels in the first word of the first line is the same as the number of vowels in the first word of the second line. 
  * The number of vowels in the second word of the first line is the same as the number of vowels in the second word of the second line. 
  * The last vowel of the first line is the same as the last vowel of the second line. Note that there may be consonants after the vowel. 



Also, letters "a", "e", "o", "i", and "u" are vowels. Note that "y" is never vowel.

For example of a beautiful lyric, 

"hello hellooowww" 

"whatsup yowowowow" 

is a beautiful lyric because there are two vowels each in "hello" and "whatsup", four vowels each in "hellooowww" and "yowowowow" (keep in mind that "y" is not a vowel), and the last vowel of each line is "o".

For example of a not beautiful lyric, 

"hey man"

"iam mcdic" 

is not a beautiful lyric because "hey" and "iam" don't have same number of vowels and the last vowels of two lines are different ("a" in the first and "i" in the second).

How many beautiful lyrics can you write from given words? Note that you cannot use a word more times than it is given to you. For example, if a word is given three times, you can use it at most three times.

Input

The first line contains single integer n (1 ≤ n ≤ 10^{5}) — the number of words.

The i-th of the next n lines contains string s_{i} consisting lowercase alphabet letters — the i-th word. It is guaranteed that the sum of the total word length is equal or less than 10^{6}. Each word contains at least one vowel.

Output

In the first line, print m — the number of maximum possible beautiful lyrics.

In next 2m lines, print m beautiful lyrics (two lines per lyric).

If there are multiple answers, print any.

Examples

Input


14
wow
this
is
the
first
mcdics
codeforces
round
hooray
i
am
proud
about
that


Output


3
about proud
hooray round
wow first
this is
i that
mcdics am


Input


7
arsijo
suggested
the
idea
for
this
problem


Output


0


Input


4
same
same
same
differ


Output


1
same differ
same same

Note

In the first example, those beautiful lyrics are one of the possible answers. Let's look at the first lyric on the sample output of the first example. "about proud hooray round" forms a beautiful lyric because "about" and "hooray" have same number of vowels, "proud" and "round" have same number of vowels, and both lines have same last vowel. On the other hand, you cannot form any beautiful lyric with the word "codeforces".

In the second example, you cannot form any beautiful lyric from given words.

In the third example, you can use the word "same" up to three times.

Solution (in JAVA):

Solution:
import java.io.*;
import java.math.*;
import java.util.*;
import java.util.stream.*;
import static java.lang.Math.abs;
import static java.lang.Math.min;
import static java.lang.Math.max;
import static java.lang.Math.sqrt;
import static java.lang.Integer.signum;

@SuppressWarnings("unchecked")
public class P1182C {

// 14 wow this is the first mcdics codeforces round hooray i am proud about that

  class Word implements Comparable<Word> {
    String w;
    int gc, n;
    char lg;

    public Word(int n, String s) {
      this.n = n;
      w = s;

      for (int i = 0; i < s.length(); i++) {
        if ((s.charAt(i) == 'a') || (s.charAt(i) == 'e') || (s.charAt(i) == 'o') ||
            (s.charAt(i) == 'i') || (s.charAt(i) == 'u')) {
          gc++;
          lg = s.charAt(i);
        }
      }
    }

    @Override public int compareTo(Word w) {
      return ((gc != w.gc) ? (gc - w.gc) : (lg - w.lg));
    }

    @Override public boolean equals(Object o) {
      return (this.compareTo((Word)o) == 0);
    }

    @Override public String toString() {
      return w;
    }
  }

  //-------------------------------------

  public void run() throws Exception {
    int n = nextInt(), k = 0;
    Word [] wa = new Word [n];
    boolean [] wu = new boolean [n];
    for (int i = 0; i < n; wa[i] = new Word(i, next()), i++);
    StringBuilder ans = new StringBuilder();

    Word [] tw = Arrays.copyOf(wa, n);
    shuffle(tw);
    Arrays.sort(tw);

    List<int []> lw = new ArrayList();
    for (int i = n - 2; i >= 0; i--) {
      if ((tw[i].lg != '\0') && tw[i].equals(tw[i + 1])) {
        lw.add(new int [] { tw[i].n, tw[i + 1].n });
        wu[tw[i].n] = wu[tw[i + 1].n] = true;
        i--;
      }
    }
    tw = null;

    TreeMap<Integer, TreeSet<Integer>> gcws = new TreeMap();
    for (int i = 0; i < n; i++) {
      if (!wu[i]) {
        Word w = wa[i];
        TreeSet<Integer> ws = gcws.get(w.gc);
        if (ws == null) { ws = new TreeSet(); gcws.put(w.gc, ws); }
        ws.add(i);
      }
    }
    wu = null;

    // crearing
    for (Iterator<Map.Entry<Integer, TreeSet<Integer>>> i = gcws.entrySet().iterator(); i.hasNext();) {
      if (i.next().getValue().size() < 2) { i.remove(); }
    }

    for (int i = lw.size() - 1; (i >= 0) && (gcws.size() > 0); lw.remove(i), i--) {
      int lw1 = lw.get(i)[0], lw2 = lw.get(i)[1];

      TreeSet<Integer> ws = gcws.firstEntry().getValue();
      int fw1 = ws.pollFirst(), fw2 = ws.pollFirst();
      if (ws.size() < 2) { gcws.pollFirstEntry(); }

      k++;
      ans.append(wa[fw1]).append(' ').append(wa[lw1]).append('\n')
         .append(wa[fw2]).append(' ').append(wa[lw2]).append('\n');
    }

    for (int i = lw.size() - 2; i >= 0; i -= 2, k++) {
      ans.append(wa[lw.get(i)[0]]).append(' ').append(wa[lw.get(i + 1)[0]]).append('\n')
         .append(wa[lw.get(i)[1]]).append(' ').append(wa[lw.get(i + 1)[1]]).append('\n');
    }

    println(k + "\n" + ans);
  }

  public static void main(String... args) throws Exception {
    br = new BufferedReader(new InputStreamReader(System.in));
    pw = new PrintWriter(new BufferedOutputStream(System.out));
    new P1182C().run();
    br.close();
    pw.close();
    System.err.println("\n[Time : " + (System.currentTimeMillis() - startTime) + " ms]");
  }

  static long startTime = System.currentTimeMillis();
  static BufferedReader br;
  static PrintWriter pw;
  StringTokenizer stok;

  String nextToken() throws IOException {
    while (stok == null || !stok.hasMoreTokens()) {
      String s = br.readLine();
      if (s == null) { return null; }
      stok = new StringTokenizer(s);
    }
    return stok.nextToken();
  }

  void print(byte b) { print("" + b); }
  void print(int i) { print("" + i); }
  void print(long l) { print("" + l); }
  void print(double d) { print("" + d); }
  void print(char c) { print("" + c); }
  void print(Object o) {
    if (o instanceof int[]) { print(Arrays.toString((int [])o));
    } else if (o instanceof long[]) { print(Arrays.toString((long [])o));
    } else if (o instanceof char[]) { print(Arrays.toString((char [])o));
    } else if (o instanceof byte[]) { print(Arrays.toString((byte [])o));
    } else if (o instanceof short[]) { print(Arrays.toString((short [])o));
    } else if (o instanceof boolean[]) { print(Arrays.toString((boolean [])o));
    } else if (o instanceof float[]) { print(Arrays.toString((float [])o));
    } else if (o instanceof double[]) { print(Arrays.toString((double [])o));
    } else if (o instanceof Object[]) { print(Arrays.toString((Object [])o));
    } else { print("" + o); }
  }
  void printsp(int [] a) { for (int i = 0, n = a.length; i < n; print(a[i] + " "), i++); }
  void print(String s) { pw.print(s); }
  void println() { println(""); }
  void println(byte b) { println("" + b); }
  void println(int i) { println("" + i); }
  void println(long l) { println("" + l); }
  void println(double d) { println("" + d); }
  void println(char c) { println("" + c); }
  void println(Object o) { print(o); println(); }
  void println(String s) { pw.println(s); }
  int nextInt() throws IOException { return Integer.parseInt(nextToken()); }
  long nextLong() throws IOException { return Long.parseLong(nextToken()); }
  double nextDouble() throws IOException { return Double.parseDouble(nextToken()); }
  char nextChar() throws IOException { return (char) (br.read()); }
  String next() throws IOException { return nextToken(); }
  String nextLine() throws IOException { return br.readLine(); }
  int [] readInt(int size) throws IOException {
    int [] array = new int [size];
    for (int i = 0; i < size; i++) { array[i] = nextInt(); }
    return array;
  }
  long [] readLong(int size) throws IOException {
    long [] array = new long [size];
    for (int i = 0; i < size; i++) { array[i] = nextLong(); }
    return array;
  }
  double [] readDouble(int size) throws IOException {
    double [] array = new double [size];
    for (int i = 0; i < size; i++) { array[i] = nextDouble(); }
    return array;
  }
  String [] readLines(int size) throws IOException {
    String [] array = new String [size];
    for (int i = 0; i < size; i++) { array[i] = nextLine(); }
    return array;
  }

  int gcd(int a, int b) {
    if (a == 0) return Math.abs(b); if (b == 0) return Math.abs(a);
    a = Math.abs(a); b = Math.abs(b);
    int az = Integer.numberOfTrailingZeros(a), bz = Integer.numberOfTrailingZeros(b);
    a >>>= az; b >>>= bz;
    while (a != b) {
      if (a > b) { a -= b; a >>>= Integer.numberOfTrailingZeros(a); }
            else { b -= a; b >>>= Integer.numberOfTrailingZeros(b); }
    }
    return (a << Math.min(az, bz));
  }

  long gcd(long a, long b) {
    if (a == 0) return Math.abs(b); if (b == 0) return Math.abs(a);
    a = Math.abs(a); b = Math.abs(b);
    int az = Long.numberOfTrailingZeros(a), bz = Long.numberOfTrailingZeros(b);
    a >>>= az; b >>>= bz;
    while (a != b) {
      if (a > b) { a -= b; a >>>= Long.numberOfTrailingZeros(a); }
            else { b -= a; b >>>= Long.numberOfTrailingZeros(b); }
    }
    return (a << Math.min(az, bz));
  }

  void shuffle(int [] a) { // RANDOM shuffle
    Random r = new Random();
    for (int i = a.length - 1, j, t; i >= 0; j = r.nextInt(a.length), t = a[i], a[i] = a[j], a[j] = t, i--);
  }

  void shuffle(int [] a, int m) { // QUICK shuffle
    for (int i = 0, n = a.length, j = m % n, t; i < n; t = a[i], a[i] = a[j], a[j] = t, i++, j = (i * m) % n);
  }

  void shuffle(long [] a) {
    Random r = new Random();
    for (int i = a.length - 1; i >= 0; i--) {
      int j = r.nextInt(a.length);
      long t = a[i]; a[i] = a[j]; a[j] = t;
    }
  }

  void shuffle(Object [] a) {
    Random r = new Random();
    for (int i = a.length - 1; i >= 0; i--) {
      int j = r.nextInt(a.length);
      Object t = a[i]; a[i] = a[j]; a[j] = t;
    }
  }

  int [] sort(int [] a) {
    final int SHIFT = 16, MASK = (1 << SHIFT) - 1, SIZE = (1 << SHIFT) + 1;
    int n = a.length, ta [] = new int [n], ai [] = new int [SIZE];
    for (int i = 0; i < n; ai[(a[i] & MASK) + 1]++, i++);
    for (int i = 1; i < SIZE; ai[i] += ai[i - 1], i++);
    for (int i = 0; i < n; ta[ai[a[i] & MASK]++] = a[i], i++);
    int [] t = a; a = ta; ta = t;
    ai = new int [SIZE];
    for (int i = 0; i < n; ai[(a[i] >> SHIFT) + 1]++, i++);
    for (int i = 1; i < SIZE; ai[i] += ai[i - 1], i++);
    for (int i = 0; i < n; ta[ai[a[i] >> SHIFT]++] = a[i], i++);
    return ta;
  }

  void flush() {
    pw.flush();
  }

  void pause() {
    flush(); System.console().readLine();
  }
}