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#include <bits/stdc++.h>

using namespace std;

typedef unsigned uint;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ldbl;
typedef pair<int, int> pii;
typedef pair<uint, uint> puu;
typedef pair<ll, ll> pll;
typedef pair<ull, ull> pull;
typedef pair<double, double> pdd;
typedef vector<int> vi;
typedef vector<uint> vu;
typedef vector<ll> vll;
typedef vector<ull> vull;
typedef vector<pii> vpii;
typedef vector<puu> vpuu;
typedef vector<pll> vpll;
typedef vector<pull> vpull;
typedef vector<string> vstr;
typedef vector<double> vdbl;
typedef vector<ldbl> vldbl;
#define pb push_back
#define ppb pop_back
#define pfr push_front
#define ppfr pop_front
#define emp emplace
#define empb emplace_back
#define be begin
#define rbe rbegin
#define all(x) (x).be(), (x).end()
#define rall(x) (x).rbe(), (x).rend()
#define fir first
#define sec second
#define mkp make_pair
#define brif(cond) if (cond) break
#define ctif(cond) if (cond) continue
#define retif(cond) if (cond) return
void canhazfast() {ios_base::sync_with_stdio(false);cin.tie(nullptr);cout.tie(nullptr);}
template<typename T> T gcd(T a, T b) {return b ? gcd(b, a%b) : a;}
template<typename T> T extgcd(T a, T b, T &x, T &y)
{
    T x0 = 1, y0 = 0, x1 = 0, y1 = 1;
    while (b) {
        T q = a/b; a %= b; swap(a, b);
        x0 -= q*x1; swap(x0, x1);
        y0 -= q*y1; swap(y0, y1);
    }
    x = x0; y = y0; return a;
}
int ctz(uint x) {return __builtin_ctz(x);}
int ctzll(ull x) {return __builtin_ctzll(x);}
int clz(uint x) {return __builtin_clz(x);}
int clzll(ull x) {return __builtin_clzll(x);}
int popcnt(uint x) {return __builtin_popcount(x);}
int popcntll(ull x) {return __builtin_popcountll(x);}
int bsr(uint x) {return 31^clz(x);}
int bsrll(ull x) {return 63^clzll(x);}

#define MX 3008

bool vis[MX];
int h[MX], p[MX], q[MX], pos[MX];

int main()
{
    canhazfast();

    int n;
    constexpr int mx = 3000;
    vector<vi> cycles;
    vpii ans[2];

    cin >> n;
    for (int i = 1; i <= n; ++i) {
        cin >> h[i];
        pos[h[i]] = i;
    }
    for (int i = 1, j = 0; i <= mx; ++i) {
        if (pos[i]) p[pos[i]] = ++j;
    }
    //cerr << "p ="; for (int i = 1; i <= n; ++i) cerr << ' ' << p[i]; cerr << '\n';
    //cerr << "cycles:\n";
    for (int i = 1; i <= n; ++i) {
        ctif(vis[i]);
        cycles.empb(vi());
        for (int u = i; !vis[u]; u = p[u]) {
            cycles.back().pb(u);
            vis[u] = true;
            //cerr << ' ' << u;
        }
        //cerr << '\n';
    }
    ///for (int i = 1; i <= n; ++i) q[p[i]] = i;
    for (const vi &c : cycles) {
        int k = (int)c.size();
        ctif(k < 2);
        if (k == 2) {
            ans[0].empb(c[0], c[1]);
            continue;
        }
        /// > 2
        int m = (k-1)/2;
        for (int i = 0; i < m; ++i) ans[0].empb(c[i], c[2*m-i]);
        for (int i = k%2; i <= m; ++i) ans[1].empb(c[i], c[2*m+1-i]);
    }
    cout << (ans[1].size() ? 2 : (ans[0].size() ? 1 : 0)) << '\n';
    for (int i : {0, 1}) {
        int k = (int)ans[i].size();
        ctif(k == 0);
        cout << 2*k << '\n';
        for (int j = 0; j < k; ++j) cout << ans[i][j].fir << ' ';
        for (int j = k-1; j >= 0; --j) cout << ans[i][j].sec << ' ';
        cout << '\n';
    }

    return 0;
}