#include <bits/stdc++.h>
using namespace std;

vector<int> a;
int n, m, k;

int main() {
    cin >> n >> m;

    a.assign(n+1, 0);

    for(int i = 1; i <= m; i++) {
        cin >> a[i];
    }

    for(int i = m-1; i >= 1; i--) {
        if(a[i] < a[i+1]-1) {
            vector<int> b(n+1);
            for(int j = 1; j <= i; j++) {
                if(j<i) b[j] = a[j];
                else if (j==i) b[j] = a[j]-1;
            }
            int now = n;
            for(int j = m; j > i; j--) {
                b[j] = now;
                now--;
            }

            for(int j = 1; j <= m; j++) {
                cout << b[j] << ' ';
            }
            cout << endl;
            i = -10;
        }
    }

}