3
2 1 1
 6
6 2 6 2 4 2
 2
1 2
 8
2 1 2 2 6 5 6 6
 18
2 3 4 5 2 7 8 9 10 7 11 12 14 15 13 17 18 18
 7
1 2 3 4 5 6 7
 7
4 3 2 6 3 5 2
 7
7 5 3 1 2 1 5
 7
1 6 4 4 5 6 7

1
2 2 1  0
6 2 6 2 4 2  1 
1 1 
 2 
2 2 2 2 6 2 6 6 
 5 
2 3 4 5 11 7 8 9 10 11 11 11 14 15 11 17 18 11 
 6 
1 1 1 1 1 1 1 
 1
4 3 3 6 3 5 2  1
7 5 3 1 3 1 5  4 
1 6 4 1 1 1 1 

#include <bits/stdc++.h>
using namespace std;
int n, root;
int p[200001];
vector<int> adj[200001];
int vis[200001], delta = 0;
int dfs(int u, int z = -1) {
  if (vis[u] == 2) return 0;
  if (vis[u] == 1) return 1;
  vis[u] = 1;
  for (int v : adj[u]) {
    if (v != z) {
      int r = dfs(v, u);
      if (r == 1) {
        if (root == -1) root = u;
        p[u] = root;
        delta++;
        return 2;
      }
      if (r == 2) return 2;
    }
  }
  vis[u] = 2;
  return 0;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cin >> n;
  root = -1;
  for (int i = 1; i <= n; i++) {
    cin >> p[i];
    if (i == p[i])
      root = i;
    else {
      adj[p[i]].push_back(i);
    }
  }
  for (int i = 1; i <= n; i++) dfs(i);
  for (int i = 1; i <= n; i++) {
    if (p[i] == i && i != root) {
      p[i] = root;
      delta++;
    }
  }
  cout << delta << '\n';
  for (int i = 1; i <= n; i++) cout << p[i] << ' ';
  cout << '\n';
  return 0;
}
