#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;
}
}
int dfs2(int x, int p, vector<vector<int>> &AR, vector<vector<int>> &ans, int &cur, int depth, int add)
{
int sub = 1, pos = cur - depth;
cur += add;
for (int i = 0; i < AR[x].size(); i++)
{
if (AR[x][i] == p)
continue;
sub += dfs2(AR[x][i], x, AR, ans, cur, depth + 1, add);
}
for (int i = 0; i < sub; i++)
{
ans[pos][x] = p;
pos += add;
}
return sub;
}
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);
}
}
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 centre = -1, leaf = -1;
vector<int> banned(N);
for (int i = 0; i < N; i++)
{
if (centre != -1)
break;
for (int j = 0; j < N; j++)
{
if (centre != -1)
break;
vector<int> temp(N);
for (int k = 0; k < AR2[i].size(); k++)
temp[AR2[i][k]] = 1;
for (int k = 0; k < AR2[j].size(); k++)
temp[AR2[j][k]] = 0;
if (temp[j] == 0)
continue;
for (int k = 0; k < N; k++)
{
if (temp[k] && k != j && k != i)
{
centre = i;
leaf = j;
}
}
}
}
if (centre == -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(centre, leaf);
AR[centre].push_back(leaf);
AR[leaf].push_back(centre);
for (int j = 0; j < AR2[leaf].size(); j++)
banned[AR2[leaf][j]] = 1;
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)
continue;
for (int j = 0; j < AR2[i].size(); j++)
{
if (AR2[i][j] == centre)
continue;
if (UF.merge(i, AR2[i][j]))
{
AR[i].push_back(AR2[i][j]);
AR[AR2[i][j]].push_back(i);
}
}
}
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 < 200; i++)
{
ans[i * 2][AR[centre][i % 2]] = centre;
}
for (int i = 0; i < AR[centre].size(); i++)
{
int pos = 1;
if (i == 0)
pos += 2;
int temp = dfs2(AR[centre][i], centre, AR, ans, pos, 0, (i <= 1) ? 4 : 2);
}
for (int i = 0; i < AR[centre].size(); i++)
{
for (int j = 1; j < 400; j += 2)
ans[j][AR[centre][i]] = centre;
}
int cur = 400, last = centre;
dfs(centre, centre, 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;
}
}
