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 const N = 2e5 + 41;
int n, p[N], root, ans, was[N];
vector<int> cyc;
void print() {
  printf("%d\n", ans);
  for (int i = 1; i <= n; ++i) {
    if (i > 1) {
      printf(" ");
    }
    printf("%d", p[i]);
  }
  exit(0);
}
void findRoot() {
  for (int i = 1; i <= n; ++i) {
    if (p[i] == i) {
      if (root) {
        ++ans;
        p[i] = root;
      } else {
        root = i;
      }
    }
  }
}
void dfs(int u) {
  was[u] = 1;
  int to = p[u];
  if (to == u) {
    was[u] = 2;
    return;
  }
  if (was[to] == 2) {
  } else {
    if (was[to] == 1) {
      cyc.push_back(u);
    } else {
      dfs(to);
    }
  }
  was[u] = 2;
}
int main() {
  scanf("%d", &n);
  for (int i = 1; i <= n; ++i) {
    scanf("%d", &p[i]);
  }
  findRoot();
  for (int i = 1; i <= n; ++i) {
    if (!was[i]) {
      dfs(i);
    }
  }
  if (!root) {
    root = cyc[0];
  }
  for (int i = 0; i < cyc.size(); ++i) {
    p[cyc[i]] = root;
    ++ans;
  }
  print();
  return 0;
}
