#include <bits/stdc++.h>
using namespace std;
//using namespace atcoder;
struct fast_ios { fast_ios(){ cin.tie(0); ios::sync_with_stdio(false); cout << fixed << setprecision(20); }; } fast_ios_;
#define FOR(i, begin, end) for(int i=(begin);i<(end);i++)
#define REP(i, n) FOR(i,0,n)
#define IFOR(i, begin, end) for(int i=(end)-1;i>=(begin);i--)
#define IREP(i, n) IFOR(i,0,n)
#define Sort(v) sort(v.begin(), v.end())
#define Reverse(v) reverse(v.begin(), v.end())
#define all(v) v.begin(),v.end()
#define SZ(v) ((int)v.size())
#define Lower_bound(v, x) distance(v.begin(), lower_bound(v.begin(), v.end(), x))
#define Upper_bound(v, x) distance(v.begin(), upper_bound(v.begin(), v.end(), x))
#define chmax(a, b) a = max(a, b)
#define chmin(a, b) a = min(a, b)
#define bit(n) (1LL<<(n))
#define debug(x) cout << #x << "=" << x << endl;
#define vdebug(v) { cout << #v << "=" << endl; REP(i_debug, (int)v.size()){ cout << v[i_debug] << ","; } cout << endl; }
#define mdebug(m) { cout << #m << "=" << endl; REP(i_debug, (int)m.size()){ REP(j_debug, (int)m[i_debug].size()){ cout << m[i_debug][j_debug] << ","; } cout << endl;} }
#define pb push_back
#define fi first
#define se second
#define int long long
#define INF 1000000000000000000
template<typename T> istream &operator>>(istream &is, vector<T> &v){ for (auto &x : v) is >> x; return is; }
template<typename T> ostream &operator<<(ostream &os, vector<T> &v){ for(int i = 0; i < (int)v.size(); i++) { cout << v[i]; if(i != (int)v.size() - 1) cout << endl; }; return os; }
template<typename T1, typename T2> ostream &operator<<(ostream &os, pair<T1, T2> p){ cout << '(' << p.first << ',' << p.second << ')'; return os; }
template<typename T> void Out(T x) { cout << x << endl; }
template<typename T1, typename T2> void chOut(bool f, T1 y, T2 n) { if(f) Out(y); else Out(n); }

using vec = vector<int>;
using mat = vector<vec>;
using Pii = pair<int, int>;
using v_bool = vector<bool>;
using v_Pii = vector<Pii>;

//int dx[4] = {1,0,-1,0};
//int dy[4] = {0,1,0,-1};
//char d[4] = {'D','R','U','L'};

//const int mod = 1000000007;
const int mod = 998244353;

struct fast_random
{
    uint32_t x;

    fast_random(int seed = 2463534242): x(seed){}

    uint32_t xorshift(){
        x ^= (x << 13);
        x ^= (x >> 17);
        x ^= (x << 5);
        return x;
    }

    //random integer in [a, b]
    uint32_t randint(uint32_t a, uint32_t b){
        return a + xorshift() % (b - a + 1);
    }

    double uniform(){
        return (double)xorshift() / UINT32_MAX;
    }

    double uniform(double a, double b){
        return a + uniform() * (b - a);
    }

};
fast_random rng;

vec random_permutatiuon(int N){
    vec p(N);
    v_bool used(N + 1);
    REP(i, N){
        while(true){
            int x = rng.randint(1, N);
            if(!used[x]){
                used[x] = true;
                p[i] = x;
                break;
            }
        }
    }
    return p;
}

bool verify(mat ans){
    map<vec, int> cnt;
    for(auto q: ans){
        cnt[q] += 1;
        if(cnt[q] >= 3) return false;
    }
    return true;
}

signed main(){

    int N; cin >> N;

    priority_queue<Pii> que;
    vec num(2 * N);
    FOR(i, 1, 2 * N){
        que.push(Pii(i, i));
        num[i] = i;
    }
    
    mat ans(2 * N - 1, vec(N));
    vec cols;
    //vec p = random_permutatiuon(2 * N - 1);
    vec p;
    REP(i, N - 1){
        if(i % 2 == 0){
            p.pb(i + 1);
            p.pb(2 * N - 2 - i);
        }else{
            p.pb(2 * N - 2 - i);
            p.pb(i + 1);
        }
    }
    p.pb(2 * N - 1);

    REP(i, 2 * N - 1) REP(_, p[i]) cols.pb(p[i]);
    int now = 0;
    REP(k, N) REP(i, 2 * N - 1){
        ans[i][k] = cols[now];
        now++;
    }
    REP(i, 2 * N - 1) Sort(ans[i]);
    assert(verify(ans));

    cout << 2 * N - 1 << endl;
    REP(i, 2 * N - 1){
        REP(k, N) cout << ans[i][k] << ' ';
        cout << endl;
    }

    return 0;
}