#include <bits/stdc++.h>
using namespace std;
class UnionFind
{
private:
vector<int> p;
public:
UnionFind(int x)
{
p.assign(x, 0);
for (int i = 0; i < x; i++)
p[i] = i;
}
int find(int x) { return (x == p[x]) ? x : p[x] = find(p[x]); }
bool merge(int a, int b)
{
int x = find(a), y = find(b);
if (x == y)
return 0;
p[x] = y;
return 1;
}
};
void dfs(int x, int p, vector<vector<int>> &AR, vector<vector<int>> &ans, int &cur, int &last)
{
if (x != last)
{
ans[cur][x] = last;
cur++;
last = x;
}
for (int i = 0; i < AR[x].size(); i++)
{
if (AR[x][i] == p)
continue;
dfs(AR[x][i], x, AR, ans, cur, last);
ans[cur][x] = last;
cur++;
last = x;
}
}
void dfs2(int x, int p, vector<vector<int>> &AR, vector<int> &par, vector<int> &deb, int &cur, int depth)
{
par[x] = p;
deb[x] = cur - depth;
cur += 2;
for (int i = 0; i < AR[x].size(); i++)
{
if (AR[x][i] == p)
continue;
dfs2(AR[x][i], x, AR, par, deb, cur, depth + 1);
}
}
void dfs3(int x, vector<int> &occ, vector<vector<int>> &AR, int &num, int nono)
{
num++;
occ[x] = 1;
for (int i = 0; i < AR[x].size(); i++)
{
if (occ[AR[x][i]])
continue;
if (AR[x][i] == nono)
continue;
dfs3(AR[x][i], occ, AR, num, nono);
}
}
void dfs4(int x, vector<vector<int>> &AR, vector<int> &occ)
{
occ[x] = 1;
for (int i = 0; i < AR[x].size(); i++)
{
if (occ[AR[x][i]])
continue;
dfs4(AR[x][i], AR, occ);
}
}
int good(int leaf, int centre, vector<vector<int>> &AR, vector<int> &banned)
{
for (int i = 0; i < AR[leaf].size(); i++)
{
if (AR[leaf][i] == centre)
break;
if (i == AR[leaf].size() - 1)
return 0;
}
int N = banned.size();
banned.assign(N, 0);
for (int i = 0; i < AR[leaf].size(); i++)
{
banned[AR[leaf][i]] = 1;
}
vector<int> occ(N, 0);
occ[leaf] = 1;
occ[centre] = 1;
for (int i = 0; i < AR[centre].size(); i++)
{
if (AR[centre][i] == leaf)
continue;
if (banned[AR[centre][i]])
continue;
dfs4(AR[centre][i], AR, occ);
}
for (int i = 0; i < N; i++)
if (occ[i] == 0)
return 0;
return 1;
}
int main()
{
int N, M;
cin >> N >> M;
vector<vector<int>> AR(N), AR2(N);
UnionFind UF(N);
for (int i = 0; i < M; i++)
{
int a, b;
cin >> a >> b;
AR2[a].push_back(b);
AR2[b].push_back(a);
}
int leaf = -1, centre = -1;
vector<int> banned(N);
for (int i = 0; i < N; i++)
{
for (int j = 0; j < N; j++)
{
if (i == j)
continue;
if (good(i, j, AR2, banned))
{
leaf = i;
centre = j;
break;
}
}
if (leaf != -1)
break;
}
if (leaf == -1)
{
int N2 = N;
if (N % 2 == 0)
N2++;
vector<int> perm(N2), C(N2);
for (int i = 0; i < N2; i++)
{
perm[i] = i;
if (i <= N2 / 2)
{
C[i] = i;
C[N2 - i - 1] = i;
}
}
cout << 2 * N2 << endl;
for (int i = 0; i < N2; i++)
{
for (int k = 0; k < 2; k++)
{
for (int j = 0; j < N; j++)
{
cout << C[perm[j]] << ' ';
}
cout << '\n';
}
swap(perm[0], perm[N2 - 1]);
for (int j = 1; j < N2 - 1; j++)
swap(perm[j], perm[j - 1]);
}
return 0;
}
UF.merge(leaf, centre);
AR[leaf].push_back(centre);
AR[centre].push_back(leaf);
for (int i = 0; i < AR2[centre].size(); i++)
{
if (AR2[centre][i] == leaf)
continue;
if (banned[AR2[centre][i]])
continue;
if (UF.merge(centre, AR2[centre][i]))
{
AR[centre].push_back(AR2[centre][i]);
AR[AR2[centre][i]].push_back(centre);
for (int j = 0; j < AR2[AR2[centre][i]].size(); j++)
banned[AR2[AR2[centre][i]][j]] = 1;
}
}
for (int i = 0; i < N; i++)
{
if (i == centre || i == leaf)
continue;
for (int j = 0; j < AR2[i].size(); j++)
{
if (AR2[i][j] == centre || AR2[i][j] == leaf)
continue;
if (UF.merge(i, AR2[i][j]))
{
AR[i].push_back(AR2[i][j]);
AR[AR2[i][j]].push_back(i);
}
}
}
vector<int> par(N), deb(N, 1000);
vector<vector<int>> ans(600, vector<int>(N));
for (int i = 0; i < 600; i++)
for (int j = 0; j < N; j++)
ans[i][j] = j;
for (int i = 0; i < 400; i++)
{
ans[i][leaf] = centre;
}
for (int i = 0; i < AR[centre].size(); i++)
{
if (AR[centre][i] == leaf)
continue;
int pos = 0;
dfs2(AR[centre][i], centre, AR, par, deb, pos, 0);
}
for (int i = 0; i < N; i++)
{
if (i == leaf || i == centre)
continue;
for (int j = deb[i]; j < 400; j += 2)
{
ans[j][i] = par[i];
}
}
int cur = 400, last = leaf;
dfs(leaf, leaf, AR, ans, cur, last);
cout << 600 << endl;
for (int i = 0; i < 600; i++)
{
for (int j = 0; j < N; j++)
{
cout << ans[i][j] << ' ';
}
cout << endl;
}
}
