#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#include <stack>
using namespace std;
//ifstream fin("bfs.in");
//ofstream fout("bfs.out");
//ifstream fin("dfs.in");
//ofstream fout("dfs.out");
ifstream fin("biconex.in");
ofstream fout("biconex.out");
int viz[100001];
int min_pos[100001];
stack <int> node_order;
int counter=0;
vector<int>biconex[100001];
class grafMare
{
    int N,M;
    vector <int> graf[100001];
    public:
        grafMare(){};
        void citireBFS();
        void citireDFS();
        void actualDFS(int);
        void citire_biconex();
        void add_a_biconex(int,int);
        void DFS_biconex(int,int,int);
        
};
void grafMare::add_a_biconex(int first, int i)
{
    counter++;
    while(node_order.top()!=i)
    {
        biconex[counter].push_back(node_order.top());
        node_order.pop();
    }
    biconex[counter].push_back(node_order.top());
    node_order.pop();
    biconex[counter].push_back(first);
}
void grafMare::citire_biconex()
{
    fin>>N>>M;
    for(int i=0;i<M;i++)
    {
        int a,b;
        fin>>a>>b;
        graf[a].push_back(b);
        graf[b].push_back(a);
    }
}
void grafMare::DFS_biconex(int current_node, int current_pos, int tata_node)
{
    min_pos[current_node]=current_pos;
    node_order.push(current_node);
    for(auto i : graf[current_node])
    {
        if(!min_pos[i]) //dfs
        {
            DFS_biconex(i, current_pos+1, current_node);
            min_pos[current_node]=min(min_pos[current_node], min_pos[i]+1); // actualizez levelul minim in caz ca baiatul urmator are traseu mai scurt de la un nod mai devreme, dupa ce intra in else if(desen 2, 7-8, 1-8)
            if(min_pos[i] > current_pos) // asta e punct de articulatie, daca n ar respecta cond asta, ins ca exista alt traseu care mentine conditia cu conex
                add_a_biconex(current_node,i);
        }
        else if(i!=tata_node)
            min_pos[current_node]=min(min_pos[current_node], min_pos[i]+1);
    }    
}
void grafMare::citireBFS()
{
    fin>>N>>M;
    int start;
    fin>>start;
    int a,b;
    for(int i=0;i<M;i++)
    {
        fin>>a>>b;
        graf[a].push_back(b);
    }
    int sol[100001];
    for(int i=0;i<N+1;i++)
        sol[i]=-1;
    queue <int> q;
    q.push(start);
    sol[start]=0;
 
    while(!q.empty())
    {
        int first=q.front();
        q.pop();
        for(int vecin : graf[first])
        {
            if(sol[vecin]==-1)
            {
                sol[vecin]=sol[first]+1;
                q.push(vecin);
            }
        }
    }
    for(int i=1;i<N+1;i++)
        fout<<sol[i]<<" ";
}
void grafMare::actualDFS(int index)
{
    for(int vecin : graf[index])
        if(!viz[vecin])
        {
            viz[vecin]=1;
            actualDFS(vecin);
        }
}
void grafMare::citireDFS()
{
    fin>>N>>M;
    int start=1;
    int a,b;
    for(int i=0;i<M;i++)
    {
        fin>>a>>b;
        graf[a].push_back(b);
        graf[b].push_back(a);
    }
    for(int i=0;i<N+1;i++)
        viz[i]=0;
    for(int i=1;i<N+1;i++)
        if(!viz[i])
        {
            counter++;
            actualDFS(i);
        }
    fout<<counter;
}
int main()
{
    grafMare gm;
    //gm.citireBFS();
    gm.citire_biconex();
    fout<<counter;
    for(int i=0;i<counter;i++)
    {
        for(auto j : biconex[i])
            fout<<j<<" ";
        fout<<"\n";
    }
}