#include <bits/stdc++.h>
using namespace std;
const int maxn = 2e5 + 10;
const int mod = 998244353;
const int inf = 0x3fffffff;
int n, p[maxn], father[maxn], b[maxn];
void init() {
  for (int i = 1; i <= n; i++) father[i] = i;
}
int find_father(int x) {
  int a = x;
  while (x != father[x]) x = father[x];
  while (a != father[a]) {
    int z = a;
    a = father[a];
    father[z] = x;
  }
  return x;
}
void Union(int a, int b) {
  int faA = find_father(a);
  int faB = find_father(b);
  if (faA != faB) father[faA] = faB;
}
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  cin >> n;
  init();
  int root = 0;
  for (int i = 1; i <= n; i++) {
    cin >> p[i];
    Union(i, p[i]);
    if (i == p[i]) root = i;
  }
  int k = find_father(root);
  int cnt = 0;
  for (int i = 1; i <= n; i++) {
    int t = find_father(i);
    if (b[t] == 0) {
      cnt++;
      if (t != k) p[t] = root;
    }
    b[t]++;
  }
  bool flag = false;
  for (int i = 1; i <= n; i++) {
    if (p[i] == 0) {
      if (!flag) {
        p[i] = i;
        root = i;
        flag = true;
      } else
        p[i] = root;
    }
  }
  if (flag)
    cout << cnt;
  else
    cout << cnt - 1;
  cout << endl;
  for (int i = 1; i <= n; i++) cout << p[i] << " ";
  return ~~(0 - 0);
}
