#include<cstdio>
#include<algorithm>
using namespace std;
int v[5000001],n,nr,k,i,j,a;

int main(){
    FILE *f=fopen("interclasari.in","r");
    FILE *g=fopen("interclasari.out","w");
    fscanf(f,"%d",&k);
    nr=0;
    for(i=1;i<=k;i++){
        fscanf(f,"%d",&n);
        for(j=1;j<=n;j++){
            fscanf(f,"%d",&a);
            nr++;
            v[nr]=a;
        }
    }
    sort(v+1,v+nr+1);
    fprintf(g,"%d\n",nr);
    for(i=1;i<=nr;i++){
        fprintf(g,"%d ",v[i]);
    }
    fclose(f);
    fclose(g);
    return 0;
}