#include<bits/stdc++.h>
using namespace std;
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
#define int long long
#define ordered_set tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update>
#define fall(i,a,b) for(int i=a;i<=b;i++)
#define rfall(i,a,b) for(int i=a;i>=b;i--)
#define pb push_back
#define sz(x) (int)x.size()
#define all(x) x.begin(),x.end()
#define pb push_back
const int MAXN=3e5+10;
typedef pair<int,int> pii;
int n,m;
void show(vector<int> a){
for(auto x:a) cout<<x<<" ";
cout<<"\n";
}
int32_t main(){
std::ios_base::sync_with_stdio(false);
cin.tie(NULL);
cin>>n>>m;
fall(i,1,m){
int a,b; cin>>a>>b;
}
cout<<4*(n-1)<<"\n";
fall(k,1,n-1){
vector<int> cor(n+1);
vector<int> at;
fall(i,1,n){
if(cor[i]) at.pb(cor[i]);
else{
cor[i]=i;
if(i+k<=n) cor[i+k]=i;
at.pb(cor[i]);
}
}
show(at); show(at);
at.clear();
fill(all(cor),0);
fall(i,1,k) at.pb(i);
fall(i,k+1,n){
if(cor[i]) at.pb(cor[i]);
else{
cor[i]=i;
if(i+k<=n) cor[i+k]=i;
at.pb(cor[i]);
}
}
show(at); show(at);
}
}
