#include <bits/stdc++.h>
using namespace std;
template <typename Arg1>
void __f(const char* name, Arg1&& arg1) {
  cerr << name << " : " << arg1 << "\n";
}
template <typename Arg1, typename... Args>
void __f(const char* names, Arg1&& arg1, Args&&... args) {
  const char* comma = strchr(names + 1, ',');
  cerr.write(names, comma - names) << " : " << arg1 << " , ";
  __f(comma + 1, args...);
}
inline long long int gcd(long long int a, long long int b) {
  a = abs(a), b = abs(b);
  while (b) a = a % b, swap(a, b);
  return a;
}
inline long long int power(long long int a, long long int p) {
  long long int res = 1, x = a;
  while (p) {
    if (p & 1) res = (res * x);
    x = (x * x), p >>= 1;
  }
  return res;
}
inline long long int mul_mod(long long int a, long long int p,
                             long long int m) {
  long long int res = 0, x = a % m;
  while (p) {
    if (p & 1) res = (res + x) % m;
    x = (x << 1) % m, p >>= 1;
  }
  return res;
}
inline long long int big_mod(long long int a, long long int p,
                             long long int m) {
  long long int res = 1 % m, x = a % m;
  while (p) {
    if (p & 1) res = (res * x) % m;
    x = (x * x) % m, p >>= 1;
  }
  return res;
}
long long int ext_gcd(long long int A, long long int B, long long int* X,
                      long long int* Y) {
  long long int x2, y2, x1, y1, x, y, r2, r1, q, r;
  x2 = 1, y2 = 0;
  x1 = 0, y1 = 1;
  for (r2 = A, r1 = B; r1 != 0;
       r2 = r1, r1 = r, x2 = x1, y2 = y1, x1 = x, y1 = y) {
    q = r2 / r1, r = r2 % r1;
    x = x2 - (q * x1), y = y2 - (q * y1);
  }
  *X = x2;
  *Y = y2;
  return r2;
}
inline long long int mod_inv(long long int a, long long int m) {
  long long int x, y;
  ext_gcd(a, m, &x, &y);
  x %= m;
  if (x < 0) x += m;
  return x;
}
const int INF = 1e9 + 9;
int ara[55];
set<int> ST;
vector<int> soldiers;
int main() {
  int n, k;
  scanf("%d %d", &n, &k);
  for (int i = 0; i < n; i++) {
    scanf("%d", &ara[i]);
  }
  int cnt = 0;
  while (true) {
    soldiers.clear();
    int sum = 0;
    for (int i = 0; i < n; i++) {
      sum += ara[i];
      soldiers.push_back(ara[i]);
      if (ST.find(sum) == ST.end()) {
        ST.insert(sum);
        printf("%d", soldiers.size());
        for (int j = 0, len = soldiers.size(); j < len; j++) {
          printf(" %d", soldiers[j]);
        }
        printf("\n");
        k--;
        if (k == 0) {
          return 0;
        }
      }
    }
    random_shuffle(ara, ara + n);
  }
  return 0;
}
