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 ll = long long;
using vi = vector<int>;
using pi = pair<int, int>;
const int mod = 1e9 + 7;
const ll inf = ll(0x3f3f3f3f3f3f3f3f);
const double PI = acos(-1), eps = 1e-9;
const int mxn = 2e5, mxa = 1e5, mxk = 2e3;
int n, a[mxn + 5], link[mxn + 5], sze[mxn + 5];
int find(int x) {
  while (x != link[x]) x = link[x];
  return x;
}
bool same(int a, int b) { return find(a) == find(b); }
void unite(int a, int b) {
  a = find(a), b = find(b);
  if (sze[a] < sze[b]) swap(a, b);
  sze[a] += sze[b];
  link[b] = a;
}
void solve() {
  cin >> n;
  for (int i = 1; i <= n; ++i) {
    link[i] = i;
    sze[i] = 1;
  }
  for (int i = 1; i <= n; ++i) {
    cin >> a[i];
    if (find(i) == find(a[i]) && i != a[i])
      a[find(i)] = -1;
    else
      unite(i, a[i]);
  }
  int par = -1, ans = 0;
  for (int i = 1; i <= n; ++i) {
    if (a[i] == i) {
      par = i;
      break;
    }
  }
  for (int i = 1; i <= n; ++i) {
    if (a[i] == -1) {
      if (par == -1) par = i;
      a[i] = par;
      ++ans;
      unite(i, par);
    }
  }
  for (int i = 1; i <= n; ++i) {
    if (find(i) != find(par)) {
      a[find(i)] = par;
      unite(find(i), par);
      ++ans;
    }
  }
  cout << ans << '\n';
  for (int i = 1; i <= n; ++i) cout << a[i] << ' ';
  cout << '\n';
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  int t;
  t = 1;
  while (t-- > 0) solve();
}
