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;
using li = long long;
using ld = long double;
using pii = pair<int, int>;
const li INF = 1e18;
const int M = 1e9 + 7;
const int N = 2e5 + 13;
int p[N];
vector<int> g[N];
int ans = 0;
int used[N];
int root = -1;
int dfs1(int v) {
  if (v == root) {
    return -1;
  }
  used[v] = 1;
  int u = p[v];
  int res = -1;
  if (used[u] == 0) {
    res = dfs1(u);
  } else if (used[u] == 1) {
    res = u;
  }
  used[v] = 2;
  return res;
}
int main() {
  int n;
  cin >> n;
  for (int i = 0; i < n; i++) {
    cin >> p[i];
    p[i]--;
  }
  for (int i = 0; i < n; i++) {
    if (p[i] == i) {
      if (root == -1) {
        root = i;
      } else {
        ans++;
        p[i] = root;
      }
    }
    g[p[i]].push_back(i);
  }
  if (root == -1) {
    root = dfs1(0);
    p[root] = root;
    ans++;
  }
  for (int i = 0; i < n; i++) {
    if (used[i] == 0) {
      int v = dfs1(i);
      if (v != -1) {
        ans++;
        p[v] = root;
      }
    }
  }
  cout << ans << endl;
  for (int i = 0; i < n; i++) {
    cout << p[i] + 1 << ' ';
  }
}
