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 main() {
  int n;
  scanf("%d", &n);
  vector<int> p(n + 1);
  set<int> done, visited;
  vector<vector<int> > S(n + 1);
  int index = -1;
  for (int i = 1; i <= n; i++) {
    scanf("%d", &p[i]);
    S[p[i]].push_back(i);
    if (p[i] == i) index = i;
  }
  int node, counter = 0;
  for (int i = 1; i <= n; i++) {
    if (done.find(i) != done.end()) continue;
    visited.clear();
    stack<int> dfs;
    dfs.push(i);
    while (!dfs.empty()) {
      node = dfs.top();
      dfs.pop();
      if (visited.find(node) != visited.end()) {
        if (index == -1) {
          index = node;
          counter++;
          p[node] = node;
        } else {
          p[node] = index;
          if (p[node] != node) counter++;
        }
        break;
      }
      visited.insert(node);
      for (int j = 0; j < S[node].size(); j++) {
        if (done.find(S[node][j]) == done.end()) {
          dfs.push(S[node][j]);
        }
      }
    }
    for (set<int>::iterator it = visited.begin(); it != visited.end(); it++) {
      done.insert(*it);
    }
  }
  printf("%d\n", counter);
  for (int i = 1; i <= n; i++) {
    printf("%d ", p[i]);
  }
}
