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.util.*;

import javax.lang.model.util.ElementScanner6;

import java.io.*;

public class Main{

    public static void main(String[] args) {

        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader inp = new InputReader(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        Solver solver = new Solver();
        solver.solve(inp, out);
        out.close();
        
        }



    static class Solver {


        class Node implements Comparable<Node>{
            int i;
            long c;
        
            Node(int i,long c)
            {
                this.i=i;
                this.c=c;


            }

        public int compareTo(Node n)
            {
                if(this.c==n.c)
                {
                    return Integer.compare(this.i, n.i);
                }
                return Long.compare(this.c, n.c);
            }
        }

        public boolean done(int[] sp,int[] par)
        {
            int root;

            root=findSet(sp[0],par);
            
        for(int i=1;i<sp.length;i++)
        {
                if(root!=findSet(sp[i], par))
                    return false;
        }
        return true;
        }
    public int findSet(int i,int[] par)
    {
        int x =i;
            boolean flag =false;
            while(par[i]>=0)
            {
                flag = true;
                i=par[i];
            }
            if(flag)
                par[x]=i;
            return i;
    }

    public void unionSet(int i,int j,int[] par)
    {
            int x = findSet(i, par);
            int y = findSet(j, par);
            if(x<y)
            {
                par[y]=x;
            }
            else
            {
                par[x]=y;
            }
    }

    public  long pow(long a, long b, long MOD) {
            if (b == 0) {
                return 1;
            }
            if (b == 1) {
                return a;
            }
            long val = pow(a, b / 2, MOD);
            if (b % 2 == 0) {
                return val * val % MOD;
            } else {
                return val * (val * a % MOD) % MOD;

            }
        
        }


        public void minPrimeFactor(int n,int[] s)
        {
            boolean prime[] = new boolean[n+1];
            Arrays.fill(prime, true);
            s[1]=1;
            s[2]=2;
            for(int i=4;i<=n;i+=2)
            {
                prime[i]=false;
                s[i]=2;
            }

            for(int i=3;i<=n;i+=2)
            {
                if(prime[i])
                {
                    s[i]=i;
                    for(int j=2*i;j<=n;j+=i)
                    {
                        prime[j]=false;
                        s[j]=i;
                    }
                }
            }
            
        }

        
        // public void findAllPrime(int n,ArrayList<Node> al,int s[])
        // {
        //     int curr = s[n];
        //     int cnt = 1;
        //     while(n>1)
        //     {
        //         n/=s[n];
        //         if(curr==s[n])
        //         {
        //             cnt++;
        //             continue;

        //         }
        //         Node n1 = new Node(curr,cnt);
        //         al.add(n1);

        //         curr=s[n];
        //         cnt=1;
        //     }
        // }

        

        public int binarySearch(int n,int k)
        {
            int left=1;
            int right=100000000+5;
            int ans=0;
            while(left<=right)
            {
                int mid = (left+right)/2;
                if(n/mid>=k)
                {
                    left = mid+1;
                    ans=mid;
                }
                else
                {
                    right=mid-1;
                }
            }

            return ans;
        }
        public boolean checkPallindrom(String s)
        {
            char ch[] = s.toCharArray();

            for(int i=0;i<s.length()/2;i++)
            {
                if(ch[i]!=ch[s.length()-1-i])
                    return false;
            }
            return true;
        }


        public void dfs_util(ArrayList<Integer>[] al,boolean vis[],int x,int g,int arr[],int[] count)
        {
                
            vis[x] = true;
            count[0]++;
            arr[x]=g;
          
            // System.out.println("x "+x);
                for(int i=0;i<al[x].size();i++)
                {
                    
                    if(!vis[al[x].get(i)])
                    {
                        // System.out.println("s.size "+s.size());
                        dfs_util(al, vis, al[x].get(i),g,arr,count);   
                        
                    }    
                    
                }

            
              
            
            
            return ;
        }

        public void dfs(ArrayList<Integer>[] al,int arr[],int arr1[])
        {
            
            boolean vis[] = new boolean[al.length];
           
            int g =0;
            int count[]= new int[1];
            
            for(int i=0;i<al.length;i++)
            { 
             
               
                    if(!vis[i])
                    {
                        count[0]=0;
                        dfs_util(al,vis,i,g,arr,count);
                        arr1[g]=count[0];
                        g++;
                        
                       
                    }
                   
            }

           


        }

        public void remove(ArrayList<Integer>[] al,int x)
        {
            for(int i=0;i<al.length;i++)
            {
                for(int j=0;j<al[i].size();j++)
                {

                    if(al[i].get(j)==x)
                        al[i].remove(j);

                }
            }
        }

        public long gcd(long a, long b) 
        { 
            if (a == 0) 
                return b; 
            return gcd(b % a, a); 
        }


        public void printDivisors(long n,ArrayList<Long> al) 
        { 
            // Note that this loop runs till square root 
            for (long i=2; i<=Math.sqrt(n); i++) 
            { 
                if (n%i==0) 
                { 
                    // If divisors are equal, print only one 
                    if (n/i == i) 
                    {
                        
                            al.add(i);
                    }
                      
        
                    else // Otherwise print both 
                    {   
                            al.add(i); 
                            al.add(n/i);
                    }
                        
                } 
            } 
        } 

        public static long constructSegment(long seg[],long arr[], int low,int high,int pos)
        {
            if(low==high)
            {
                seg[pos] = arr[low]; 
                return seg[pos];
            }
            int mid = (low+high)/2;
            long t1=constructSegment(seg, arr,low , mid,(2*pos)+1);
            long t2=constructSegment(seg,arr,mid+1,high,(2*pos)+2);
            seg[pos] = t1+t2;
            return seg[pos];

        }
        public static long querySegment(long seg[],int low,int high,int qlow, int qhigh,int pos)
        {
            
             if(qlow<=low&&qhigh>=high)
             {
                return seg[pos];
             }
             else if(qlow>high||qhigh<low )
             {
                 return 0;
             }
             else{
                long ans=0;
                int mid=(low+high)/2;
                ans+=querySegment(seg,low , mid, qlow, qhigh,  (2*pos)+1);
                ans+=querySegment(seg, mid+1, high, qlow, qhigh, (2*pos)+2);
               return ans; 
             }

        }
        public static int lcs( char[] X, char[] Y, int m, int n ) 
        { 
            if (m == 0 || n == 0) 
            return 0; 
            if (X[m-1] == Y[n-1]) 
            return 1 + lcs(X, Y, m-1, n-1); 
            else
            return Integer.max(lcs(X, Y, m, n-1), lcs(X, Y, m-1, n)); 
        } 

        public static long recursion(long start,long end,long cnt[],int a, int b)
        {

            long min=0;
            long count=0;
            int ans1=-1;
            int ans2=-1;
            int l=0;
            int r=cnt.length-1;
            while(l<=r)
            {
                int mid=(l+r)/2;
                if(cnt[mid]>=start)
                {
                    ans1=mid;
                    r=mid-1;
                }
                else
                {
                    l=mid+1;
                }
            }

            l=0;
            r=cnt.length-1;
            while(l<=r)
            {
                int mid=(l+r)/2;
                if(cnt[mid]<=end)
                {
                    ans2=mid;
                    l=mid+1;
                }
                else
                {
                    r=mid-1;
                }
            }
            
            if(ans1==-1||ans2==-1||ans2<ans1)
            {
                // System.out.println("min1 "+min);
                min=a;
                return a;

            }
            else
            {
                min=b*(end-start+1)*(ans2-ans1+1);
            }
            if(start==end)
            {
                // System.out.println("min "+min);
                return min;
            }
            long mid = (end+start)/2;
            min = Long.min(min,recursion(start, mid, cnt, a, b)+recursion(mid+1, end, cnt, a, b));
            // System.out.println("min "+min);
            return min;
        }

       



      

        private void solve(InputReader inp, PrintWriter out1) {
         
               
            int n = inp.nextInt();
            ArrayList<String > al = new ArrayList<String>();
            String s[] = new String[n];
            int ans[][] = new int[1000000][5];
           
            for(int i=0;i<n;i++)
            {
                s[i]= inp.next();
            }
            for(int i=0;i<ans.length;i++)
            {
                for(int j=0;j<5;j++)
                {
                    ans[i][j]=-1;
                }
            }
            for(int i=0;i<n;i++)
            {
             int count=0;
             char last='a';
                for(int j=0;j<s[i].length();j++)
                {
                    if(s[i].charAt(j)=='u'||s[i].charAt(j)=='o'||s[i].charAt(j)=='i'||s[i].charAt(j)=='e'||s[i].charAt(j)=='a')
                     {
                         last=s[i].charAt(j);
                         count++;
                     }
                    
                }
                if(last=='a')
                {
                    if(ans[count][0]==-1)
                        ans[count][0]=i;
                    else
                    {
                        al.add(s[i]);
                        al.add(s[ans[count][0]]);
                        ans[count][0]=-1;


                    }

                }
                if(last=='e')
                {
                    if(ans[count][1]==-1)
                        ans[count][1]=i;
                    else
                    {
                        al.add(s[i]);
                        al.add(s[ans[count][1]]);
                        ans[count][1]=-1;


                    }
                }
                if(last=='i')
                {
                    if(ans[count][2]==-1)
                    ans[count][2]=i;
                else
                {
                    al.add(s[i]);
                    al.add(s[ans[count][2]]);
                    ans[count][2]=-1;


                }
                }
                if(last=='o')
                {
                    if(ans[count][3]==-1)
                    ans[count][3]=i;
                    else
                    {
                        al.add(s[i]);
                        al.add(s[ans[count][3]]);
                        ans[count][3]=-1;


                    }
                }
                if(last=='u')
                {
                    if(ans[count][4]==-1)
                    ans[count][4]=i;
                    else
                    {
                        al.add(s[i]);
                        al.add(s[ans[count][4]]);
                        ans[count][4]=-1;


                    }
                }
            }

            int count = al.size();
            count/=2;
            int temp=0;
            int count1=0;
            ArrayList<String> al1 = new ArrayList<String>();
            for(int i=0;i<n;i++)
            {
                temp=-1;
                for(int j=0;j<5;j++)
                {
                    if(ans[i][j]!=-1)
                    {
                        if(temp==-1)
                        {
                            temp=ans[i][j];
                        }
                        else
                        {
                            al1.add(s[temp]);
                            al1.add(s[ans[i][j]]);
                            temp=-1;
                            count1++;
                            if(count1>=count)
                            {
                                break;
                            }
                        }
                    }
                }
            }
            count1=Math.min(count,count1);
            // System.out.println(count+" "+count1);
            int ans1 = count1;
            ans1+=(count-count1)/2;

            System.out.println(ans1);
            int l=0;
            int k=0;
            for(int i=0;i<ans1;i++)
            {
                if(k>=al1.size())
                {
                    System.out.println(al.get(l)+" "+al.get(l+2));
                    System.out.println(al.get(l+1)+" "+al.get(l+3));
                    l+=4;

                }
                else
                {
                    System.out.println(al1.get(k)+" "+al.get(l));
                    System.out.println(al1.get(k+1)+" "+al.get(l+1));
                    k+=2;
                    l+=2;
                }
            }

           

        }
}





    static class InputReader {
        BufferedReader reader;
        StringTokenizer tokenizer;

        InputReader(InputStream stream) {
            reader = new BufferedReader(new InputStreamReader(stream), 32768);
            tokenizer = null;
        }

        String next() {
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return tokenizer.nextToken();
        }

        public int nextInt() {
            return Integer.parseInt(next());
        }

        public long nextLong() {
            return Long.parseLong(next());
        }
    }
}
class ele{
    long value;
    long i;
    boolean flag;
    public ele(long value,long i)
    {
        this.value = value;
        this.i=i;
        this.flag = false;
    }
}