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:
// Working program using Reader Class 
import java.io.*; 
import java.io.FileInputStream; 
import java.io.IOException; 
import java.io.InputStreamReader;
import java.math.BigInteger;
import java.util.*; 

public class Main 
{ 
	static class Reader 
	{ 
		final private int BUFFER_SIZE = 1 << 16; 
		private DataInputStream din; 
		private byte[] buffer; 
		private int bufferPointer, bytesRead; 

		public Reader() 
		{ 
			din = new DataInputStream(System.in); 
			buffer = new byte[BUFFER_SIZE]; 
			bufferPointer = bytesRead = 0; 
		} 

		public Reader(String file_name) throws IOException 
		{ 
			din = new DataInputStream(new FileInputStream(file_name)); 
			buffer = new byte[BUFFER_SIZE]; 
			bufferPointer = bytesRead = 0; 
		} 

		public String readLine() throws IOException 
		{ 
			byte[] buf = new byte[64]; // line length 
			int cnt = 0, c; 
			while ((c = read()) != -1) 
			{ 
				if (c == '\n') 
					break; 
				buf[cnt++] = (byte) c; 
			} 
			return new String(buf, 0, cnt); 
		} 

		public int nextInt() throws IOException 
		{ 
			int ret = 0; 
			byte c = read(); 
			while (c <= ' ') 
				c = read(); 
			boolean neg = (c == '-'); 
			if (neg) 
				c = read(); 
			do
			{ 
				ret = ret * 10 + c - '0'; 
			} while ((c = read()) >= '0' && c <= '9'); 

			if (neg) 
				return -ret; 
			return ret; 
		} 

		public long nextLong() throws IOException 
		{ 
			long ret = 0; 
			byte c = read(); 
			while (c <= ' ') 
				c = read(); 
			boolean neg = (c == '-'); 
			if (neg) 
				c = read(); 
			do { 
				ret = ret * 10 + c - '0'; 
			} 
			while ((c = read()) >= '0' && c <= '9'); 
			if (neg) 
				return -ret; 
			return ret; 
		} 

		public double nextDouble() throws IOException 
		{ 
			double ret = 0, div = 1; 
			byte c = read(); 
			while (c <= ' ') 
				c = read(); 
			boolean neg = (c == '-'); 
			if (neg) 
				c = read(); 

			do { 
				ret = ret * 10 + c - '0'; 
			} 
			while ((c = read()) >= '0' && c <= '9'); 

			if (c == '.') 
			{ 
				while ((c = read()) >= '0' && c <= '9') 
				{ 
					ret += (c - '0') / (div *= 10); 
				} 
			} 

			if (neg) 
				return -ret; 
			return ret; 
		} 

		private void fillBuffer() throws IOException 
		{ 
			bytesRead = din.read(buffer, bufferPointer = 0, BUFFER_SIZE); 
			if (bytesRead == -1) 
				buffer[0] = -1; 
		} 

		private byte read() throws IOException 
		{ 
			if (bufferPointer == bytesRead) 
				fillBuffer(); 
			return buffer[bufferPointer++]; 
		} 

		public void close() throws IOException 
		{ 
			if (din == null) 
				return; 
			din.close(); 
		} 
	} 
	 
	public static int gcd(int a, int b) 
    { 
        // Everything divides 0  
        if (a == 0 || b == 0) 
           return 0; 
       
        // base case 
        if (a == b) 
            return a; 
       
        // a is greater 
        if (a > b) 
            return gcd(a-b, b); 
        return gcd(a, b-a); 
    }
	
	public static class Node{
		HashMap<Character,ArrayList<String>> hm;
		Node(){
			hm=new HashMap<Character,ArrayList<String>>();
		}
	}
	
	public static class words{
		String a;
		String b;
		words(String ai,String bi){
			a=ai;
			b=bi;
		}
	}
	
	public static class lyrics{
		String w1l1;
		String w2l1;
		String w1l2;
		String w2l2;
		lyrics(String a,String b,String c,String d){
			w1l1=a;
			w2l1=b;
			w1l2=c;
			w2l2=d;
		}
	}

	public static void main(String[] args) throws IOException 
	{ 
		//Reader scan=new Reader(); 
		Scanner scan=new Scanner(System.in);
		PrintWriter out=new PrintWriter(System.out);
		int n=scan.nextInt();
		HashMap<Integer,Node> hm=new HashMap<Integer,Node>();
		for(int i=0;i<n;i++) {
			String s=scan.next();
			int vowel=0;
			char lastVowel='b';
			for(int j=0;j<s.length();j++) {
				char c=s.charAt(j);
				if(c=='a' || c=='i' || c=='o' || c=='u' || c=='e') {
					vowel++;
					lastVowel=c;
				}
			}
			if(!hm.containsKey(vowel)) {
				hm.put(vowel, new Node());
			}
			if(!hm.get(vowel).hm.containsKey(lastVowel)) {
				hm.get(vowel).hm.put(lastVowel, new ArrayList<String>());
			}
			hm.get(vowel).hm.get(lastVowel).add(s);
		}
		ArrayList<words> first=new ArrayList<words>();
		ArrayList<words> second=new ArrayList<words>();
		for(Map.Entry<Integer, Node> map : hm.entrySet()) {
			String a=null;
			String b=null;
			for(Map.Entry<Character, ArrayList<String>> map1 : map.getValue().hm.entrySet()) {
				int start=0;
				if(map1.getValue().size()%2==1) {
					start=1;
					if(a==null) {
						a=map1.getValue().get(0);
					}
					else {
						b=map1.getValue().get(0);
						first.add(new words(a,b));
						a=null;
						b=null;
					}
				}
				String c=null;
				String d=null;
				for(int i=start;i<map1.getValue().size();i++) {
					if(c==null) {
						c=map1.getValue().get(i);
					}
					else {
						d=map1.getValue().get(i);
						second.add(new words(c,d));
						c=null;
						d=null;
					}
				}
			}
		}
		ArrayList<lyrics> al=new ArrayList<lyrics>();
		int fp=0;
		int sp=0;
		while(true) {
			String a=null;
			String b=null;
			String c=null;
			String d=null;
			if(fp<first.size()) {
				a=first.get(fp).a;
				b=first.get(fp).b;
				fp++;
			}
			else if(sp<second.size()) {
				a=second.get(sp).a;
				b=second.get(sp).b;
				sp++;
			}
			else {
				break;
			}
			if(sp<second.size()) {
				c=second.get(sp).a;
				d=second.get(sp).b;
				sp++;
			}
			else{
				break;
			}
			al.add(new lyrics(a,b,c,d));
		}
		out.println(al.size());
		for(int i=0;i<al.size();i++) {
			out.println(al.get(i).w1l1 +" "+al.get(i).w1l2);
			out.println(al.get(i).w2l1+" "+al.get(i).w2l2);
		}
		out.close();
	} 
}