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#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
typedef vector<int> VI;
typedef basic_string<int> BI;
typedef long long ll;
typedef pair<int,int> PII;
typedef double db;
mt19937 mrand(1); 
const ll mod=1000000007;
int rnd(int x) { return mrand() % x;}
ll powmod(ll a,ll b) {ll res=1;a%=mod; assert(b>=0); for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;}
ll gcd(ll a,ll b) { return b?gcd(b,a%b):a;}
// head

const int N=3010;
vector<VI> cyc;
int h[N],n,vis[N];
int main() {
	scanf("%d",&n);
	VI v;
	rep(i,1,n+1) scanf("%d",&h[i]),v.pb(h[i]);
	sort(all(v));
	rep(i,1,n+1) {
		h[i]=lower_bound(all(v),h[i])-v.begin()+1;
		//printf("? %d %d\n",i,h[i]);
	}
	int ms=0;
	rep(i,1,n+1) if (!vis[i]) {
		int p=i;
		VI cc;
		vis[i]=1;
		while (1) {
			cc.pb(p);
			p=h[p];
			if (vis[p]) break;
			vis[p]=1;
		}
		//printf("? %d\n",SZ(cc));
		cyc.pb(cc);
		ms=max(ms,SZ(cc));
	}
	if (ms==1) {
		puts("0");
		return 0;
	}
	auto printp=[&](vector<PII> pc) {
		printf("%d\n",2*SZ(pc));
		VI cc;
		rep(i,0,SZ(pc)) cc.pb(pc[i].fi);
		per(i,0,SZ(pc)) cc.pb(pc[i].se);
		for (auto x:cc) printf("%d ",x);
		puts("");
	};
	if (ms==2) {
		puts("1");
		vector<PII> pc;
		for (auto cc:cyc) if (SZ(cc)==2) pc.pb(mp(cc[0],cc[1]));
		printp(pc);
		return 0;
	}
	puts("2");
	vector<PII> pc;
	for (auto cc:cyc) {
		int m=SZ(cc)/2*2;
		for (int i=0;2*i<m;i++) {
			pc.pb(mp(cc[i],cc[m-1-i]));
			swap(h[cc[i]],h[cc[m-1-i]]);
		}
	}
	printp(pc);
	for (int i=1;i<=n;i++) assert(h[h[i]]==i);
	pc.clear();
	for (int i=1;i<=n;i++) if (h[i]!=i)	 {
		int j=h[i];
		pc.pb(mp(i,j)); swap(h[i],h[j]);
	}
	printp(pc);
}