#include <cstdio>
#include <set>
using namespace std;
int N, K;
const int MAX_N = 50000 + 5;
const int MAX_K = 10 + 5;
int book[MAX_N] = { 0 };
struct Node {
int val, num;
bool operator < (const Node& a) const {
return a.num == num ? val<a.val : num>a.num;
}
};
int main() {
scanf("%d%d", &N, &K);
set<Node> s;
for (int i = 0; i < N; i++) {
int num;
scanf("%d", &num);
if (i != 0) {
printf("%d:", num);
int temp = 0;
for (auto it = s.begin(); temp < K && it != s.end(); it++, temp++) {
printf(" %d", it->val);
}
printf("\n");
}
auto it = s.find(Node{ num, book[num] });
if (it != s.end()) {
s.erase(it);
}
book[num]++;
s.insert(Node{ num,book[num] });
}
return 0;
}
/*
Sample Input:
12 3
3 5 7 5 5 3 2 1 8 3 8 12
Sample Output:
5: 3
7: 3 5
5: 3 5 7
5: 5 3 7
3: 5 3 7
2: 5 3 7
1: 5 3 2
8: 5 3 1
3: 5 3 1
8: 3 5 1
12: 3 5 8
*/
