#include <bits/stdc++.h>
#include <utility>
#include <vector>

#define ll long long
#define ull unsigned long long
#define pii std::pair<int, int>

#define IO (std::string) "biconex"
std::ifstream fin(IO + ".in");
std::ofstream fout(IO + ".out");

#define NMAX 100

int n, m;
std::vector<int> G[NMAX];
std::vector<std::vector<int>> sol;
std::stack<pii> stiva;
int tata[NMAX], niv[NMAX], nivmin[NMAX];
bool vis[NMAX];

void citire() {
  fin >> n >> m;

  for (int i = 1; i <= m; i++) {
    int a, b;
    fin >> a >> b;

    G[a].push_back(b);
    G[b].push_back(a);
  }
}

void build(int a, int b) {
  std::vector<int> v;
  while (!stiva.empty()) {
    pii p = stiva.top();
    stiva.pop();
    v.push_back(p.first);
    v.push_back(p.second);
    if (p == std::make_pair(a, b))
      break;
  }
  sort(v.begin(), v.end());
  v.erase(unique(v.begin(), v.end()), v.end());
  sol.push_back(v);
}
void dfs(int nod) {
  vis[nod] = 1;
  nivmin[nod] = niv[nod];
  for (int i : G[nod]) {
    if (i == tata[nod])
      continue;
    if (!vis[i]) {
      stiva.push({nod, i});
      tata[i] = nod;
      niv[i] = niv[nod] + 1;
      dfs(i);
      nivmin[nod] = std::min(nivmin[nod], nivmin[i]);
      if (nivmin[i] >= niv[nod])
        build(nod, i);
    } else
      nivmin[nod] = std::min(nivmin[nod], niv[i]);
  }
}

int main() {
  // std::cin.tie(0)->std::ios::sync_with_stdio(0);
  citire();

  dfs(1);

  fout << sol.size() << '\n';

  for (int i = 1; i <= n; i++) {
    fout << niv[n] << '\n';
  }
  for (std::vector<int> it : sol) {
    for (int k : it) {
      std::cout << k << ' ';
    }
    std::cout << '\n';
  }
  return 0;
}