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;
const int INF = (~(1 << 31)) - 5;
int n, rt;
int a[200005], vis[200005], cnt, ans;
void work(int x) {
  ++cnt;
  int t = x;
  vis[x] = cnt;
  while (!vis[a[t]]) {
    vis[a[t]] = cnt;
    t = a[t];
  }
  if (vis[a[t]] == cnt) {
    if (rt)
      if (a[t] != rt)
        ans++, a[t] = rt;
      else
        rt = t;
  }
}
int main() {
  scanf("%d", &n);
  for (int i = 1; i <= n; i++) {
    scanf("%d", &a[i]);
    if (a[i] == i) rt = i;
  }
  for (int i = 1; i <= n; i++)
    if (!vis[i]) work(i);
  cout << ans << endl;
  for (int i = 1; i <= n; i++) printf("%d ", a[i]);
  return 0;
}
