15666.cpp

// Authored by : yongjunleeme
// Co-authored by : -
// http://boj.kr/801162160382436b971d8a4bbcec798a
#include <bits/stdc++.h>
using namespace std;

int arr[10];
int num[10];
int n, m;

void func(int k, int st){
  if(k == m){
    for(int i = 0; i < m; i++) cout << arr[i] << " ";
    cout << "\n";
    return;
  }
  int tmp = -1;
  for(int i = st; i < n; i++){
    if(num[i] != tmp){
      arr[k] = num[i];
      tmp = arr[k];
      func(k+1, i);
    }
  }
}

int main(void) {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cin >> n >> m;
  for(int i = 0; i < n; i++) cin >> num[i];
  sort(num, num+n);
  func(0, 0);
}