#include <bits/stdc++.h>
using namespace std;
struct linkedListNode {
int8_t val;
linkedListNode *next = nullptr;
bool inserted = false;
};
linkedListNode preallocLinked[1000001];
int lastNodeLnkd = 0;
static linkedListNode* get_new_lnkd_node() {
return &preallocLinked[lastNodeLnkd++];
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
int N, K;
cin >> N >> K;
vector<int> values(N);
for (auto &i: values) cin >> i;
values.push_back(30);
linkedListNode *head = get_new_lnkd_node();
linkedListNode *tail = head;
stack<int> stck;
stck.push(30);
for (int i = 0; i < N; i++) {
while (stck.top() < values[i]) {
tail->next = get_new_lnkd_node();
tail = tail->next;
tail->val = stck.top();
tail->inserted = true;
stck.pop();
}
while (stck.top() > values[i]) {
int tmp = stck.top()-1;
stck.pop();
stck.push(tmp);
stck.push(tmp);
}
tail->next = get_new_lnkd_node();
tail = tail->next;
tail->val = values[i];
tail->inserted = false;
stck.pop();
}
while (stck.size()) {
tail->next = get_new_lnkd_node();
tail = tail->next;
tail->val = stck.top();
tail->inserted = true;
stck.pop();
}
head = head->next;
while (head != nullptr) {
cout << (int)head->val << ' ';
head = head->next;
}
cout << '\n';
}
