uva 1440

#pragma comment(linker, "/STACK:16777216")

#include<stdio.h>
#include<string.h>
#include<math.h>
#include<stdlib.h>
#include<ctype.h>
#include<iostream>
#include<vector>
#include<stack>
#include<queue>
#include<set>
#include<map>
#include<string>
#include<utility>
#include<algorithm>
#include<list>
using namespace std;

#define CLR(a) memset(a,0,sizeof(a))
#define SET(a) memset(a,-1,sizeof(a))
#define pb push_back
#define SZ(a) ((long)a.size())
#define ALL(a) a.begin(),a.end()
#define FOREACH(i, c) for( __typeof( (c).begin() ) i = (c).begin(); i != (c).end(); ++i )
#define AREA2(x1,y1,x2,y2,x3,y3) ( x1*(y2-y3) + x2*(y3-y1) + x3*(y1-y2) )
#define SQR(x) ((x)*(x))
#define STR string
#define IT iterator
#define ff first
#define ss second
#define MP make_pair
#define EPS 1e-9
#define INF 1000000007

#define chk(a,k) ((bool)(a&(1<<(k))))
#define set0(a,k) (a&(~(1<<(k))))
#define set1(a,k) (a|(1<<(k)))

typedef long long Long;
typedef vector<long> Vl;
typedef vector<Long> VL;
typedef pair<long,long> Pll;
typedef pair<Long,Long> PLL;

inline long FastMax(long x, long y) { return (((y-x)>>(32-1))&(x^y))^y; }
inline long FastMin(long x, long y) { return (((y-x)>>(32-1))&(x^y))^x; }

long IR[] = { 0,-1,0,1,-1,-1,1,1 };
long IC[] = { 1,0,-1,0,1,-1,-1,1 };


#define MAX_V 407
#define MAX_E MAX_V*MAX_V

struct EDGE{
    long v,c,f;
};
long nV;
long SRC,TNK;
long eI;
EDGE Edge[MAX_E+7]; // edge list
long Next[MAX_E+7]; // next pointer of vertex v
long Last[MAX_V+7]; // last index of adj edge of vertex v
long Dist[MAX_V+7]; // level from src
long Start[MAX_V+7];// temporary used for last

long N,st,tt;
vector<Pll> List;

inline void SetEdge( long u,long v,long c,long f )
{
    Edge[eI].v = v;
    Edge[eI].c = c;
    Edge[eI].f = f;
    Next[eI] = Last[u];
    Last[u] = eI++;
    Edge[eI].v = u;
    Edge[eI].c = 0;
    Edge[eI].f = 0;
    Next[eI] = Last[v];
    Last[v] = eI++;
}

long Q[MAX_V+7];
long Frnt,End;

bool Bfs( void )
{
    Frnt = End = 0;
    Q[End++] = SRC;
    long i;
    for( i=0;i<nV;i++){
        Dist[i] = INF;
    }
    Dist[SRC] = 0;
    long u,v;
    while( Frnt<End ){
        u = Q[Frnt++];
        for( i=Last[u];i!=-1;i=Next[i]){
            v = Edge[i].v;
            if( !Edge[i].c || Dist[v]<INF ) continue;
            Dist[v] = Dist[u] + 1;
            Q[End++] = v;
        }
    }
    return Dist[TNK] < INF;;
}

#define MIN( a,b ) a<b ? a:b

long AugmentPath( long u,long f )
{
    if( u==TNK ) return f;
    long Tot = 0;
    for( long &i = Start[u];i!=-1;i=Next[i] ){
        long v = Edge[i].v;
        if( !Edge[i].c ) continue;
        if( Dist[v] != Dist[u]+1 ) continue;
        long Tmp = AugmentPath( v,MIN( f,Edge[i].c ));
        Edge[i].c -= Tmp;
        Edge[i].f += Tmp;
        Edge[i ^ 1].c += Tmp;
        Edge[i ^ 1].f -= Tmp;
        Tot += Tmp;
        f -= Tmp;
        if( !f ) break;
    }
    return Tot;
}

long MaxFlow( void )
{
    long Flw = 0;
    while( Bfs()){
        memcpy( Start,Last,(nV)*sizeof(long));
        Flw += AugmentPath( SRC,2*INF );
    }
    return Flw;
}

bool IsPos( long Lim )
{
    st = N+1;
    tt = N+2;
    SRC = 0;
    TNK = N+2+1;
    nV = TNK+1;
    eI = 0;
    memset( Last,-1,nV*sizeof(long));
    long i,j;
    for( i=1;i<=N;i++ ){
        SetEdge( st,i,INF,0 );
        SetEdge( i,tt,INF,0 );
    }
    SetEdge( SRC,st,Lim,0 );
    SetEdge( tt,TNK,Lim,0 );
    long Flw = Lim;
    for( i=0;i<List.size();i++ ){
        SetEdge( List[i].ff,List[i].ss,INF,1 );
        SetEdge( List[i].ff,TNK,1,0 );
        SetEdge( SRC,List[i].ss,1,0 );
        Flw++;
    }
    //printf("%ld %ld\n",MaxFlow(),Flw );
    return MaxFlow()==Flw;
}


void FindPath( long st,long tt,vector<long> &Path )
{
    if( st==tt ) return;
    Path.pb( st );
    for( long &i = Start[st];i!=-1;i=Next[i] ){
        if( Edge[i].f<=0 ) continue;
        if( Edge[i].v==SRC || Edge[i].v==TNK ) continue;
        Edge[i].f--;
        FindPath( Edge[i].v,tt,Path );
        break;
    }
}

int main( void )
{
    long i,j,d,v,Icase,k = 0;

    //freopen("text1.txt","r",stdin );

    while( cin>>N ){
        List.clear();
        for( i=1;i<=N;i++ ){
            cin>>d;
            while( d-- ){
                cin>>v;
                List.pb( MP( i,v ) );
            }
        }
        long lo = 0,hi = List.size();;
        while( lo<hi ){
            long mi = (lo+hi)/2;
            if( IsPos( mi ) ) hi = mi;
            else lo = mi+1;
        }
        long Ans = hi;
        IsPos( Ans );
        printf("%ld\n",Ans );
        memcpy( Start,Last,(nV)*sizeof(long));
        for( i=1;i<=Ans;i++ ){
            vector<long> Path;
            FindPath( st,tt,Path );
            for( j=1;j<Path.size();j++ ){
                if( j>1 ) printf(" ");
                printf("%ld",Path[j] );
            }
            printf("\n");
        }
    }

    return 0;
}