#include<fstream>
#include<vector>
#include<algorithm>
using namespace std;
int n,k,N;
vector <int> H;
vector <int>::iterator it;

inline bool SortareHeap(int a,int b)
{
	return a>b;
}

int main()
{
	int i,j,x;
	ifstream fin("interclasari.in");
	fin>>k;
	for(i=0;i<k;i++)
	{
		fin>>n;
		N+=n;
		for(j=0;j<n;j++)
		{
			fin>>x;
			H.push_back(x);
			push_heap(H.begin(),H.end(),SortareHeap);
		}
	}
	fin.close();
	ofstream fout("interclasari.out");
	fout<<N<<"\n";
	for(i=0;i<N;i++)
	{
		fout<<H[0]<<' ';
		pop_heap(H.begin(),H.end(),SortareHeap);
		H.pop_back();
	}
	fout<<"\n";
	fout.close();
	return 0;
}