#include <fstream>
#define NMAX 5001
using namespace std;
ifstream fin("ctc.in");
ofstream fout("ctc.out");
int n,m;
int parcurs[NMAX],D[NMAX][NMAX],A[NMAX][NMAX];

void citire();
void afisare();
void DFS(int k);
void mdrumuri();
void first_idea(int x);

int main()
{
    citire();
    mdrumuri();
    int i;
    for(i=1;i<=n;i++)
    {
        if(!parcurs[i])
        {
            fout<<i<<" ";
            first_idea(i);
            fout<<"\n";
        }
    }
    return 0;
}

void citire()
{
    int x,y,i;
    fin>>n>>m;
    for(i=0;i<m;i++)
    {
        fin>>x>>y;
        A[x][y]=D[x][y]=1;
        D[i][i]=1;
    }
}

void DFS(int k,int lg)
{
    parcurs[k]=1;
    for(int i=1;i<=n;i++)
    {
        if(!parcurs[i]&&A[k][i])
        {
            DFS(i,lg+1);
        }
    }
}

void first_idea(int x)
{
    int i,j;
    parcurs[x]=1;
    for(i=1;i<=n;i++)
        if(x!=i)
            if(!parcurs[i]&&(D[x][i]&&D[i][x]))
            {
                parcurs[i]=1;
                fout<<i<<" ";
            }
}

void mdrumuri()
{
    int i,j,k;
    for(k=1;k<=n;k++)
        for(i=1;i<=n;i++)
            for(j=1;j<=n;j++)
                if(!D[i][j])
                    D[i][j]=D[i][k]&&D[k][j];
}