#include <cstdio>
#include <algorithm>
#include <cstring>
#include <queue>
using namespace std;
int n, s, i, k, val;
priority_queue < int > q;
void read()
{
    freopen("interclasari.in", "r", stdin);
    scanf("%d", &k);
    while (k --)
    {
        scanf("%d", &n);
        s += n;
        for (i = 1; i <= n; ++ i)
        {
            scanf("%d", &val);
            q.push(-val);
        }
    }
}
void write()
{
    freopen("interclasari.out", "w", stdout);
    printf("%d\n", s);
    while (s --)
    {
        printf("%d ", - q.top());
        q.pop();
    }
}
int main()
{
    read();
    write();
    return 0;
}