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#include <bits/stdc++.h>
using namespace std;
#define st first
#define nd second

const int INF = 3e3 + 7;
int n, maxsize, t[INF], zlicz[INF];
pair<int, int> p[INF];
vector<int> v[INF];
stack<int> st;

int main(){
	cin.tie(0);
	cout.tie(0);
	ios_base::sync_with_stdio(0);
	cin >> n;
	for(int i = 1; i <= n; i++){
		cin >> t[i];
		p[i].st = t[i];
		p[i].nd = i;
	}
	sort(p + 1, p + n + 1);
	for(int i = 1; i <= n; i++){
		if(p[i].nd != i && zlicz[i] == 0){
			v[p[i].nd].push_back(i);
			v[i].push_back(p[i].nd);
			zlicz[p[i].nd] = 1;
			zlicz[i] = 1;
		}
		if(maxsize < v[i].size()){
			maxsize = v[i].size();
		}
	}
	cout << maxsize << endl;
	if(maxsize == 0){
		cout << 0;
		return 0;
	}
	if(maxsize == 1){
		for(int i = 1; i <= n; i++){
			if(v[i].size() > 0){
				cout << v[v[i][0]][0] << " ";
				st.push(v[i][0]);
				// v[v[i]].pop();
				v[v[i][0]].pop_back();	
				v[i].pop_back();
				// cout << st.top() << " ";
			}
		}
		while(!st.empty()){
			cout << st.top() << " ";
			st.pop();
		}
	}
	/*for(int i = 1; i <= n; i++){
		for(int j = 0; j < v[i].size(); j++){
			cout << v[i][j] << " ";
		}
		cout << '\n';
	}*/

	
}