#include <bits/stdc++.h>
using namespace std;
using ll = long long;
template <class t, class u>
void chmax(t& first, u second) {
  if (first < second) first = second;
}
template <class t, class u>
void chmin(t& first, u second) {
  if (second < first) first = second;
}
template <class t>
using vc = vector<t>;
template <class t>
using vvc = vc<vc<t>>;
using pi = pair<int, int>;
using vi = vc<int>;
template <class t, class u>
ostream& operator<<(ostream& os, const pair<t, u>& p) {
  return os << "{" << p.first << "," << p.second << "}";
}
template <class t>
ostream& operator<<(ostream& os, const vc<t>& v) {
  os << "{";
  for (auto e : v) os << e << ",";
  return os << "}";
}
using uint = unsigned;
using ull = unsigned long long;
template <class t, size_t n>
ostream& operator<<(ostream& os, const array<t, n>& first) {
  return os << vc<t>(first.begin(), first.end());
}
template <int i, class T>
void print_tuple(ostream&, const T&) {}
template <int i, class T, class H, class... Args>
void print_tuple(ostream& os, const T& t) {
  if (i) os << ",";
  os << get<i>(t);
  print_tuple<i + 1, T, Args...>(os, t);
}
template <class... Args>
ostream& operator<<(ostream& os, const tuple<Args...>& t) {
  os << "{";
  print_tuple<0, tuple<Args...>, Args...>(os, t);
  return os << "}";
}
template <class t>
void print(t x, int suc = 1) {
  cout << x;
  if (suc == 1) cout << "\n";
  if (suc == 2) cout << " ";
}
ll read() {
  ll i;
  cin >> i;
  return i;
}
vi readvi(int n, int off = 0) {
  vi v(n);
  for (int i = int(0); i < int(n); i++) v[i] = read() + off;
  return v;
}
template <class T>
void print(const vector<T>& v, int suc = 1) {
  for (int i = int(0); i < int(v.size()); i++)
    print(v[i], i == int(v.size()) - 1 ? suc : 2);
}
string readString() {
  string s;
  cin >> s;
  return s;
}
template <class T>
T sq(const T& t) {
  return t * t;
}
void yes(bool ex = true) {
  cout << "YES"
       << "\n";
  if (ex) exit(0);
}
void no(bool ex = true) {
  cout << "NO"
       << "\n";
  if (ex) exit(0);
}
void possible(bool ex = true) {
  cout << "POSSIBLE"
       << "\n";
  if (ex) exit(0);
}
void impossible(bool ex = true) {
  cout << "IMPOSSIBLE"
       << "\n";
  if (ex) exit(0);
}
constexpr ll ten(int n) { return n == 0 ? 1 : ten(n - 1) * 10; }
const ll infLL = LLONG_MAX / 3;
const int inf = INT_MAX / 2 - 100;
int topbit(signed t) { return t == 0 ? -1 : 31 - __builtin_clz(t); }
int topbit(ll t) { return t == 0 ? -1 : 63 - __builtin_clzll(t); }
int botbit(signed first) { return first == 0 ? 32 : __builtin_ctz(first); }
int botbit(ll first) { return first == 0 ? 64 : __builtin_ctzll(first); }
int popcount(signed t) { return __builtin_popcount(t); }
int popcount(ll t) { return __builtin_popcountll(t); }
bool ispow2(int i) { return i && (i & -i) == i; }
ll mask(int i) { return (ll(1) << i) - 1; }
bool inc(int first, int second, int c) {
  return first <= second && second <= c;
}
template <class t>
void mkuni(vc<t>& v) {
  sort(v.begin(), v.end());
  v.erase(unique(v.begin(), v.end()), v.end());
}
ll rand_int(ll l, ll r) {
  static mt19937_64 gen(chrono::steady_clock::now().time_since_epoch().count());
  return uniform_int_distribution<ll>(l, r)(gen);
}
template <class t>
void myshuffle(vc<t>& first) {
  for (int i = int(0); i < int(int(first.size())); i++)
    swap(first[i], first[rand_int(0, i)]);
}
template <class t>
int lwb(const vc<t>& v, const t& first) {
  return lower_bound(v.begin(), v.end(), first) - v.begin();
}
const int S = 2010;
const int nmax = 16;
using B = bitset<S>;
B dp[1 << nmax];
signed main() {
  cin.tie(0);
  ios::sync_with_stdio(0);
  cout << fixed << setprecision(20);
  int n, k;
  cin >> n >> k;
  vi first = readvi(n);
  dp[0][0] = 1;
  for (int bit = int(0); bit < int(1 << n); bit++) {
    for (int i = (S - 1) / k * k; i >= k; i -= k)
      if (dp[bit][i]) {
        dp[bit][i / k] = 1;
      }
    for (int i = int(0); i < int(n); i++)
      if (!(bit & 1 << i)) dp[bit | 1 << i] |= dp[bit] << first[i];
  }
  if (dp[mask(n)][1]) {
    yes(0);
    vi u(n);
    int lv = 0, rem = mask(n), cur = 1;
    while (cur) {
      if (cur * k < S && dp[rem][cur * k]) {
        cur *= k;
        lv++;
      } else {
        bool f = false;
        for (int i = int(0); i < int(n); i++)
          if (rem & 1 << i) {
            if (cur >= first[i] && dp[rem ^ 1 << i][cur - first[i]]) {
              u[i] = lv;
              rem ^= 1 << i;
              cur -= first[i];
              f = true;
              break;
            }
          }
        assert(f);
      }
    }
    for (int _ = int(0); _ < int(n - 1); _++) {
      int mx = -1;
      int x = -1, y = -1;
      for (int i = int(0); i < int(n); i++) {
        if (mx < u[i]) {
          mx = u[i];
          x = -1;
          y = -1;
        }
        if (mx == u[i]) {
          if (x == -1)
            x = i;
          else
            y = i;
        }
      }
      assert(y != -1);
      cout << first[x] << " " << first[y] << endl;
      first[x] += first[y];
      u[y] = -1;
      while (first[x] % k == 0) {
        u[x]--;
        first[x] /= k;
      }
    }
    for (int i = int(0); i < int(n); i++) {
      if (u[i] == 0) {
        assert(first[i] == 1);
      } else {
        assert(u[i] == -1);
      }
    }
  } else
    no();
}
