#include<bits/stdc++.h>
using namespace std;
const int N=2e5+5;
int n,a[N],vis[N],num;
vector<int>v;
signed main()
{
	int x=1;
	scanf("%d",&n);
	for(int i=1;i<=n;i++)scanf("%d",a+i);
	while(!vis[x])vis[x]=1,x=a[x];
	while(vis[x]==1)vis[x]++,v.push_back(x),x=a[x],num++;
	printf("%d\n",num);
	for(auto x:v)printf("%d ",x);
	return 0;
}