#include <bits/stdc++.h>
const int inf = 0x3f3f3f3f, Inf = 0x7fffffff;
const long long INF = 0x7fffffffffffffff;
const double eps = 1e-10;
unsigned int seed = 19260817;
const unsigned int _RAND_MAX_ = 4294967295u;
__inline__ __attribute__((always_inline)) unsigned int Rand() {
  return seed = seed * 998244353u + 1000000007u;
}
template <typename _Tp>
_Tp gcd(const _Tp &a, const _Tp &b) {
  return (!b) ? a : gcd(b, a % b);
}
template <typename _Tp>
__inline__ __attribute__((always_inline)) _Tp abs(const _Tp &a) {
  return a >= 0 ? a : -a;
}
template <typename _Tp>
__inline__ __attribute__((always_inline)) _Tp max(const _Tp &a, const _Tp &b) {
  return a < b ? b : a;
}
template <typename _Tp>
__inline__ __attribute__((always_inline)) _Tp min(const _Tp &a, const _Tp &b) {
  return a < b ? a : b;
}
template <typename _Tp>
__inline__ __attribute__((always_inline)) void chmax(_Tp &a, const _Tp &b) {
  (a < b) && (a = b);
}
template <typename _Tp>
__inline__ __attribute__((always_inline)) void chmin(_Tp &a, const _Tp &b) {
  (b < a) && (a = b);
}
template <typename _Tp>
__inline__ __attribute__((always_inline)) bool _cmp(const _Tp &a,
                                                    const _Tp &b) {
  return abs(a - b) <= eps;
}
template <typename _Tp>
__inline__ __attribute__((always_inline)) void read(_Tp &x) {
  register char ch(getchar());
  bool f(false);
  while (ch < 48 || ch > 57) f |= ch == 45, ch = getchar();
  x = ch & 15, ch = getchar();
  while (ch >= 48 && ch <= 57)
    x = (((x << 2) + x) << 1) + (ch & 15), ch = getchar();
  if (f) x = -x;
}
template <typename _Tp, typename... Args>
__inline__ __attribute__((always_inline)) void read(_Tp &t, Args &...args) {
  read(t);
  read(args...);
}
__inline__ __attribute__((always_inline)) int read_str(char *s) {
  register char ch(getchar());
  while (ch == ' ' || ch == '\r' || ch == '\n') ch = getchar();
  register char *tar = s;
  *tar = ch, ch = getchar();
  while (ch != ' ' && ch != '\r' && ch != '\n' && ch != EOF)
    *(++tar) = ch, ch = getchar();
  return tar - s + 1;
}
const int N = 19;
std::bitset<2005> dp[1 << 16];
int a[N];
int n, k;
int cnt[N];
int sum;
void print(int st, int s) {
  if (!st) return;
  if (s * k <= sum && dp[st][s * k]) {
    for (int i = 0; i < n; ++i) {
      if ((st >> i) & 1) {
        ++cnt[i];
      }
    }
    return print(st, s * k);
  }
  for (int i = 0; i < n; ++i) {
    if (s >= a[i] && ((st >> i) & 1) && dp[st ^ (1 << i)].test(s - a[i])) {
      return print(st ^ (1 << i), s - a[i]);
    }
  }
}
struct node {
  int val, cnt;
  __inline__ __attribute__((always_inline)) bool operator<(
      const node &o) const {
    return cnt < o.cnt;
  }
};
std::priority_queue<node> q;
int main() {
  read(n, k);
  for (int i = 0; i < n; ++i) read(a[i]), sum += a[i];
  dp[0].set(0);
  for (int st = 1; st < 1 << 16; ++st) {
    for (int i = 0; i < n; ++i) {
      if ((st >> i) & 1) {
        dp[st] |= dp[st ^ (1 << i)] << a[i];
      }
    }
    for (int i = sum / k; i >= 1; --i) {
      if (dp[st].test(i * k)) {
        dp[st].set(i);
      }
    }
  }
  if (dp[(1 << n) - 1][1]) {
    printf("YES\n");
    print((1 << n) - 1, 1);
    for (int i = 0; i < n; ++i) q.push((node){a[i], cnt[i]});
    while ((int)q.size() > 1) {
      node x = q.top();
      q.pop();
      node y = q.top();
      q.pop();
      printf("%d %d\n", x.val, y.val);
      x.val += y.val;
      while (!(x.val % k)) {
        x.val /= k;
        --x.cnt;
      }
      q.push(x);
    }
  } else {
    printf("NO\n");
  }
  return 0;
}
