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.BufferedWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;

public class Main {
	public static boolean check(char x) {
		return x=='a'||x=='e'||x=='i'||x=='o'||x=='u';
	}
	
	public static void main(String[] args) throws IOException {
		InputReader sc=new InputReader(System.in);
		PrintWriter out=new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out)));
		int n=sc.nextInt();
		String[] res=new String[n];
		ArrayList<Ans> p1=new ArrayList<Ans>();
		ArrayList<Ans> p2=new ArrayList<Ans>();
		Node[] buf=new Node[n];
		
		for(int i=0;i<n;i++) {
			res[i]=sc.next();
			char last=0;
			int cnt=0;
			for(int j=0;j<res[i].length();j++) {
				if(check(res[i].charAt(j))) {
					cnt++;
					last=res[i].charAt(j);
				}
			}
			buf[i]=new Node(cnt,last,i);
		}
		Arrays.sort(buf);
		Node temp=null;
		boolean take=false;
		for(int i=0;i<n;i++) {
			if(i+1<n&&buf[i].cnt==buf[i+1].cnt&&buf[i].last==buf[i+1].last) {
				p2.add(new Ans(buf[i].index,buf[i+1].index));
				i++;
			}
			else
				if(take&&buf[i].cnt==temp.cnt) {
					take=false;
					p1.add(new Ans(buf[i].index,temp.index));
				}
			else {
				take=true;
				temp=buf[i];
			}
		}
		out.println(Math.min(p2.size(),(p1.size()+p2.size())/2));
		int max=Math.min(p1.size(),p2.size());
		for(int i=0;i<max;i++) {
			out.println(res[p1.get(i).first]+" "+res[p2.get(i).first]);
			out.println(res[p1.get(i).second]+" "+res[p2.get(i).second]);
		}
		if(p2.size()>max) {
			for(int i=max;i+1<p2.size();i+=2) {
				out.println(res[p2.get(i).first]+" "+res[p2.get(i+1).first]);
				out.println(res[p2.get(i).second]+" "+res[p2.get(i+1).second]);
			}
		}
		out.flush();
	}
}

class Ans{
	int first;
	int second;
	
	public Ans(int first,int second) {
		this.first=first;
		this.second=second;
	}
}

class Node implements Comparable<Node>{
	char last;
	int cnt;
	int index;
	
	public Node(int cnt,char last,int index) {
		this.cnt=cnt;
		this.last=last;
		this.index=index;
	}

	@Override
	public int compareTo(Node o) {
		if(this.cnt==o.cnt) {
			return this.last-o.last;
		}
		return this.cnt-o.cnt;
	}
}

class InputReader {
    private InputStreamReader reader;
    private char[] buf;
    private int len, now;
 
    public InputReader(InputStream stream) {
        reader = new InputStreamReader(stream);
        buf = new char[1024];
        len = 0;
        now = 0;
    }
 
    public String next() throws IOException {
        if (!hasNext()) throw new NullPointerException();
        StringBuilder sb = new StringBuilder();
        while (!isSpaceChar(buf[now])) {
            sb.append(buf[now]);
            if (!move()) break;
        }
        return sb.toString();
    }
 
    public int nextInt() throws IOException {
        if (!hasNext()) throw new NullPointerException();
        boolean x = false;
        if (buf[now] == '-') {
            x = true;
            if (!move()) throw new NumberFormatException();
        }
        int ans = 0;
        while (!isSpaceChar(buf[now])) {
            if (isNum(buf[now])) ans = ans * 10 + buf[now] - '0';
            else throw new NumberFormatException();
            if (!move()) break;
        }
        return (x ? -1 : 1) * ans;
    }
 
    public String nextLine() throws IOException {
        if (!hasNextLine()) throw new NullPointerException();
        StringBuilder sb = new StringBuilder();
        while (buf[now] != '\n') {
            sb.append(buf[now]);
            if (!move()) return sb.toString();
        }
        now++;
        return sb.toString();
    }
 
    public long nextLong() throws IOException {
        if (!hasNext()) throw new NullPointerException();
        boolean x = false;
        if (buf[now] == '-') {
            x = true;
            if (!move()) throw new NumberFormatException();
        }
        long ans = 0;
        while (!isSpaceChar(buf[now])) {
            if (isNum(buf[now])) ans = ans * 10 + buf[now] - '0';
            else throw new NumberFormatException();
            if (!move()) break;
        }
        return (x ? -1 : 1) * ans;
    }
 
    public double nextDouble() throws IOException {
        return Double.parseDouble(next());
    }
 
    public int nextHexInt() throws IOException {
        if (!hasNext()) throw new NullPointerException();
        boolean x = false;
        if (buf[now] == '-') {
            x = true;
            if (!move()) throw new NumberFormatException();
        }
        int ans = 0;
        while (!isSpaceChar(buf[now])) {
            if (isHex(buf[now])) ans = ans * 16 + toHex(buf[now]);
            else throw new NumberFormatException();
            if (!move()) break;
        }
        return (x ? -1 : 1) * ans;
    }
 
    public char nextChar() throws IOException {
        if (!hasNext()) throw new NullPointerException();
        char tmp = buf[now];
        move();
        return tmp;
    }
    public int next(char[] s) throws IOException {
        if (!hasNext()) throw new NullPointerException();
        int len=0;
        while (!isSpaceChar(buf[now])&&len<s.length) {
            s[len++]=buf[now];
            if (!move()) break;
        }
        return len;
    }
    public boolean hasNext() throws IOException {
        return skip();
    }
 
    public boolean hasNextLine() throws IOException {
        return now < len || refill();
    }
 
    private boolean move() throws IOException {
        now++;
        return hasNextLine();
    }
 
    private boolean skip() throws IOException {
        if (!hasNextLine()) return false;
        while (isSpaceChar(buf[now])) {
            if (!move()) return false;
        }
        return true;
    }
 
    private boolean isSpaceChar(char c) {
        return !(c >= 33 && c <= 126);
    }
 
    private boolean isNum(char c) {
        return c >= '0' && c <= '9';
    }
 
    private boolean isHex(char c) {
        return c >= '0' && c <= '9' || c >= 'A' && c <= 'F';
    }
 
    private int toHex(char c) {
        if (c >= '0' && c <= '9') return c - '0';
        else return c - 'A' + 10;
    }
 
    private boolean refill() throws IOException {
        len = reader.read(buf);
        now = 0;
        return len > 0;
    }
}