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

main()
{
    int num_snacks;

    cin >> num_snacks;

    int snack_list[num_snacks], temp = num_snacks, element_temp;

    vector<int> stack_list;

    for (int i = 0; i < num_snacks; i++)
    {
        cin >> snack_list[i];
    }

    for (int i = 0; i < num_snacks; i++)
    {
        if (snack_list[i] == temp)
        {
            cout << snack_list[i] << " ";
            temp--;
            sort(stack_list.begin(), stack_list.end());
            for (int j = stack_list.size() - 1; j >= 0; j--)
            {
                if (stack_list[j] == temp)
                {
                    cout << stack_list[j] << " ";
                    element_temp = stack_list[j];
                    stack_list.push_back(element_temp);
                    temp--;
                }
            }
        }
        else
        {
            element_temp = snack_list[i];

            stack_list.push_back(element_temp);
        }
        cout << endl;
    }
}