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#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <queue>
#include <map>
#include <set>
#include <stack>
#include <iomanip>
#include <cmath>
#include <cstring>
#include <numeric>
#include <cstdio>
#include <list>
#include <cassert>
#include <climits>
#include <bitset>

using namespace std;

#define IN(type, name) \
  type name; \
  cin >> name;

#define For(var, constant, init) for (int var = init; var < constant; var++)

#define Sp << ' ' <<
#define End << '\n'

#define PI 3.141592653589793238462643383279502884L

#define ll long long
#define ull unsigned long long
#define uint unsigned int
#define ld long double

#define MOD 1000000007

typedef vector<int> vint;
typedef vector<ll> vll;
typedef pair<int, int> pint;
typedef pair<ll, ll> pll;

int n, r;
vector<string> v;
vector<string> out;

void rec(int len, int index, string crnt) {
  if (len == r) {
    out.push_back(crnt);
    return;
  }

  if (index == n) return;

  rec(len, index+1, crnt);
  rec(len + 1, index+1, crnt + to_string(index));
}

bool strComp(string &s1, string &s2) {
  int len1 = s1.length(), len2 = s2.length();
  int len = min(len1, len2);
  For(i, len, 0) {
    if (s1[i] < s2[i]) return true;
    else if (s1[i] > s2[i]) return false;
    else continue;
  }

  return (len1 < len2);
}

int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);

  cin >> n >> r;
  v.resize(n);
  For(i,n,0) cin >> v[i];

  sort(v.begin(), v.end(), strComp);

  rec(0, 0, "");
  sort(out.begin(), out.end(), strComp);

  for(string &s : out) {
    for(char &c : s) cout << v[c - '0'] << ' ';
    cout End;
  }

}