#include <fstream>
using namespace std;
ifstream fin("date.in");
ofstream fout("date.out");
int n,m,a[100][100];

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

int grad(int v)
{
    int g=0;
    for(int i=1;i<=n;i++)
        g=g+a[v][i];
    return g;
}
int main()
{
    citire();
    for(int i=1;i<=n;i++)
        if(grad(i)>=2)
        {
            for(int j=1;j<=n;j++)
                if(a[i][j]==1) fout<<"["<<i<<","<<j<<"] ";
            fout<<endl;
        }
    fin.close();
    fout.close();
    return 0;
}