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 MOD = 1e9 + 7;
const int SIZE = 1e6 + 10;
int a[SIZE], u[SIZE], in[SIZE], tt;
int main() {
  int r = 0;
  int(n);
  scanf("%d", &n);
  for (int i = (1); i < (n + 1); ++i) scanf("%d", &(a[i]));
  vector<int> an;
  for (int i = (1); i < (n + 1); ++i) {
    if (!u[i]) {
      tt++;
      int x = i;
      in[x] = tt;
      u[x] = 1;
      for (x = a[x]; !u[x]; x = a[x]) u[x] = 1, in[x] = tt;
      if (in[x] == tt) {
        if (x == a[x] || !r) r = x;
        an.push_back(x);
      }
    }
  }
  int ker = (a[r] == r);
  for (int i = 0; i < (((int)(an).size())); ++i) a[an[i]] = r;
  printf("%d\n", ((int)(an).size()) - ker);
  for (int i = (1); i < (n + 1); ++i) printf("%d ", a[i]);
  return 0;
}
