#include <bits/stdc++.h>
using namespace std;
using ll = long long;
int main() {
ll N, M;
cin >> N >> M;
vector<vector<ll> > adjList(N);
for (ll i = 0; i < M; i++) {
ll ui, vi;
cin >> ui >> vi;
adjList[ui].push_back(vi);
adjList[vi].push_back(ui);
}
vector<pair<ll, ll> > ij;
for (ll i = 0; i < N - 1; i++) {
for (ll j = 0; j < N - i - 1; j++) {
ij.push_back({j, j + 1});
}
}
cout << ij.size() << endl;
for (auto &l: ij) {
vector<ll> colors(N, 0);
for (ll i = 1; i <= N; i++) {
colors[i] = i;
}
colors[l.first] = colors[l.second] = 0;
for (ll i = 0; i < N; i++) {
if (i != 0) cout << " ";
cout << colors[i];
}
cout << endl;
}
}
