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 CPP):

Solution:
#include <bits/stdc++.h>
using namespace std;
template <class T>
T gcd(T a, T b) {
  if (!b) return a;
  while (b ^= a ^= b ^= a %= b)
    ;
  return a;
}
template <class T>
T max(const T& t1, const T& t2, const T& t3) {
  return max(max(t1, t2), t3);
}
template <class T>
T max(const T& t1, const T& t2, const T& t3, const T& t4) {
  return max(max(t1, t2), max(t3, t4));
}
long long fpow(long long x, long long y, long long mod = 0x7fffffffffffffffll) {
  long long ret = 1;
  while (y) {
    if (y & 1) ret *= x, ret %= mod;
    x *= x;
    x %= mod;
    y >>= 1;
  }
  return ret;
}
void ex_gcd(long long a, long long b, long long& x, long long& y) {
  if (b == 0) {
    x = a;
    y = 0;
    return;
  }
  ex_gcd(b, a % b, y, x);
  y = y - a / b * x;
}
long long modrev(long long x, long long mod) {
  long long x1, x2;
  ex_gcd(x, mod, x1, x2);
  return x1;
}
unsigned long long T_rand() { return (unsigned long long)(rand()); }
unsigned long long Rand() {
  return (T_rand() << 48) | (T_rand() << 32) | (T_rand() << 16) | T_rand();
}
template <class T>
bool PRE_INPUT_INTENGER(T& ret) {
  ;
  ret = 0;
  char c = getchar();
  if (c == -1) return 0;
  bool f = 0;
  while ((c < '0' || c > '9') && (c != -1) && (c != '-')) c = getchar();
  if (c == '-') {
    f = 1;
    c = getchar();
  }
  while (c >= '0' && c <= '9') ret *= 10, ret += c - '0', c = getchar();
  if (f) ret = -ret;
  if (c == -1) return 0;
  return 1;
}
bool input(int& ret) { return PRE_INPUT_INTENGER(ret); }
bool input(long long& ret) { return PRE_INPUT_INTENGER(ret); }
bool input(unsigned long long& ret) { return PRE_INPUT_INTENGER(ret); }
bool input(unsigned int& ret) { return PRE_INPUT_INTENGER(ret); }
template <class T>
bool PRE_INPUT_DOUBLE(T& ret) {
  ;
  ret = 0;
  char c = getchar();
  if (c == -1) return 0;
  bool f = 0;
  while ((c < '0' || c > '9') && (c != -1) && (c != '.') && (c != '-'))
    c = getchar();
  bool isright = 0;
  if (c == '-') {
    f = 1;
    c = getchar();
  }
  T t = 1;
  while ((c >= '0' && c <= '9') || (c == '.')) {
    if (c == '.')
      isright = 1;
    else {
      ret *= 10, ret += c - '0';
      if (isright) t *= 10;
    }
    c = getchar();
  }
  ret /= t;
  if (f) ret = -ret;
  if (c == -1) return 0;
  return 1;
}
bool input(double& ret) { return PRE_INPUT_DOUBLE(ret); }
bool input(float& ret) { return PRE_INPUT_DOUBLE(ret); }
bool IS_SPECIAL_CHAR(const char& ret) {
  return (ret == ' ' || ret == '\n' || ret == '\t' || ret == '\r' ||
          ret == '\v');
}
bool input(char& ret) {
  ;
  ret = getchar();
  if (ret == -1) return 0;
  while (IS_SPECIAL_CHAR(ret)) ret = getchar();
  return ~ret;
}
bool input(char* ret) {
  ;
  char c;
  if (!input(c)) return 0;
  *ret++ = c;
  while (!IS_SPECIAL_CHAR(*(ret - 1))) *ret++ = getchar();
  *(ret - 1) = 0;
  return 1;
}
template <class T1, class T2>
bool input(T1& t1, T2& t2) {
  return input(t1) && input(t2);
}
template <class T1, class T2, class T3>
bool input(T1& t1, T2& t2, T3& t3) {
  return input(t1) && input(t2) && input(t3);
}
template <class T1, class T2, class T3, class T4>
bool input(T1& t1, T2& t2, T3& t3, T4& t4) {
  return input(t1) && input(t2) && input(t3) && input(t4);
}
template <class T1, class T2, class T3, class T4, class T5>
bool input(T1& t1, T2& t2, T3& t3, T4& t4, T5& t5) {
  return input(t1) && input(t2) && input(t3) && input(t4) && input(t5);
}
template <class T>
void input(T* a, int n) {
  for (int i = 0; i <= n - 1; i++) input(a[i]);
}
template <class T>
void PRE_OUTPUT_INTENGER(const T& t) {
  ;
  if (!t) {
    putchar('0');
    return;
  }
  T key = t;
  int tt[25];
  if (key < 0) {
    putchar('-');
    key = -key;
  }
  int cnt = 0;
  while (key) tt[cnt++] = key % 10, key /= 10;
  while (cnt) putchar(tt[--cnt] + '0');
  ;
}
void output(const int& t) { PRE_OUTPUT_INTENGER(t); }
void output(const long long& t) { PRE_OUTPUT_INTENGER(t); }
void output(const unsigned long long& t) { PRE_OUTPUT_INTENGER(t); }
void output(const unsigned int& t) { PRE_OUTPUT_INTENGER(t); }
template <class T>
void PRE_OUTPUT_DOUBLE(const T& key) {
  ;
  printf("%.*f", 6, key);
  ;
}
void output(const double& t) { PRE_OUTPUT_DOUBLE(t); }
void output(const float& t) { PRE_OUTPUT_DOUBLE(t); }
void output(const char* ch) {
  ;
  int cnt = 0;
  while (ch[cnt]) putchar(ch[cnt++]);
  ;
}
void output(const char& c) {
  ;
  putchar(c);
  ;
}
void output(const string& s) { output(s.c_str()); }
template <class T1, class T2>
void output(const T1& t1, const T2& t2) {
  output(t1);
  output(t2);
}
template <class T1, class T2, class T3>
void output(const T1& t1, const T2& t2, const T3& t3) {
  output(t1);
  output(t2);
  output(t3);
}
template <class T1, class T2, class T3, class T4>
void output(const T1& t1, const T2& t2, const T3& t3, const T4& t4) {
  output(t1);
  output(t2);
  output(t3);
  output(t4);
}
template <class T1, class T2, class T3, class T4, class T5>
void output(const T1& t1, const T2& t2, const T3& t3, const T4& t4,
            const T5& t5) {
  output(t1);
  output(t2);
  output(t3);
  output(t4);
  output(t5);
}
template <class T1, class T2, class T3, class T4, class T5, class T6>
void output(const T1& t1, const T2& t2, const T3& t3, const T4& t4,
            const T5& t5, const T6& t6) {
  output(t1);
  output(t2);
  output(t3);
  output(t4);
  output(t5);
  output(t6);
}
template <class T1, class T2, class T3, class T4, class T5, class T6, class T7>
void output(const T1& t1, const T2& t2, const T3& t3, const T4& t4,
            const T5& t5, const T6& t6, const T7& t7) {
  output(t1);
  output(t2);
  output(t3);
  output(t4);
  output(t5);
  output(t6);
  output(t7);
}
template <class T>
void printal(T* a, int n) {
  for (int i = 0; i < n - 1; i++) output(a[i], ' ');
  output(a[n - 1], '\n');
}
template <class T>
void printel(T* a, int n) {
  for (int i = 0; i < n; i++) output(a[i], '\n');
}
template <class T>
void inputal(T* a, int n) {
  for (int i = 0; i <= n - 1; i++) input(a[i]);
}
const int maxn = 1e5 + 10;
struct Node {
  string s;
  int cnt;
  char last;
  bool operator<(const Node& t) const {
    if (cnt < t.cnt) return true;
    if (last < t.last) return true;
    return false;
  }
  bool operator==(const Node& t) const {
    return cnt == t.cnt && last == t.last;
  }
};
Node node[maxn];
const char* vowel = "aeiou";
bool is_vowel(char c) {
  switch (c) {
    case 'a':
    case 'e':
    case 'i':
    case 'o':
    case 'u':
      return true;
    default:
      return false;
  }
}
map<int, map<char, vector<int>>> mp;
int ans[4 * maxn];
int main() {
  int n;
  input(n);
  for (int i = 0; i <= n - 1; i++) {
    cin >> node[i].s;
    node[i].cnt = 0;
    for (const char& c : node[i].s) {
      if (is_vowel(c)) {
        ++node[i].cnt;
        node[i].last = c;
      }
    }
    if (mp.count(node[i].cnt) == 0) {
      mp[node[i].cnt] = map<char, vector<int>>();
    }
    if (mp[node[i].cnt].count(node[i].last) == 0) {
      mp[node[i].cnt][node[i].last] = vector<int>();
    }
    mp[node[i].cnt][node[i].last].push_back(i);
  }
  vector<pair<int, int>> has_same;
  map<int, vector<int>> single;
  for (const pair<int, map<char, vector<int>>>& t : mp) {
    for (const pair<char, vector<int>>& t2 : t.second) {
      for (int i = 0; i < t2.second.size(); i += 2) {
        if (i == t2.second.size() - 1) {
          if (single.count(t.first) == 0) {
            single[t.first] = vector<int>();
          }
          single[t.first].push_back(t2.second[i]);
        } else {
          has_same.push_back(make_pair(t2.second[i], t2.second[i + 1]));
        }
      }
    }
  }
  int cnt = 0;
  int last_double_idx = 0;
  for (const pair<int, vector<int>>& t : single) {
    int last_single_idx = 0;
    if (last_double_idx == has_same.size()) break;
    while (t.second.size() - last_single_idx > 1) {
      if (last_double_idx == has_same.size()) break;
      pair<int, int>& cur = has_same[last_double_idx++];
      ans[cnt++] = t.second[last_single_idx++];
      ans[cnt++] = cur.first;
      ans[cnt++] = t.second[last_single_idx++];
      ans[cnt++] = cur.second;
    }
  }
  while (last_double_idx + 1 < has_same.size()) {
    ans[cnt++] = has_same[last_double_idx].first;
    ans[cnt++] = has_same[last_double_idx + 1].first;
    ans[cnt++] = has_same[last_double_idx].second;
    ans[cnt++] = has_same[last_double_idx + 1].second;
    last_double_idx += 2;
  }
  output(cnt / 4);
  putchar('\n');
  for (int i = 0; i < cnt; i += 2) {
    output(node[ans[i]].s, " ", node[ans[i + 1]].s);
    putchar('\n');
  }
}