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 n;
int s[200005];
int p[200005];
vector<int> uv;
int fd(int x) { return (p[x] == x) ? x : (p[x] = fd(p[x])); }
int gp;
vector<int> v;
void merge(int x, int y) {
  int tx = fd(x), ty = fd(y);
  if (tx != ty) {
    gp--;
    p[tx] = ty;
  } else {
    v.push_back(x);
  }
}
void init() {
  scanf("%d", &n);
  for (int i = 1; i <= n; i++) {
    scanf("%d", &s[i]);
    p[i] = i;
    if (s[i] == i) uv.push_back(i);
  }
}
void process() {
  gp = n;
  for (int i = 1; i <= n; i++) {
    merge(i, s[i]);
  }
  if (uv.size() == 0) {
    s[v[0]] = v[0];
    uv.push_back(v[0]);
    gp++;
  }
  printf("%d\n", gp - 1);
  for (int i = 0; i < (int)v.size(); i++)
    if (v[i] != uv[0]) {
      s[v[i]] = uv[0];
    }
  for (int i = 1; i <= n; i++) printf("%d%c", s[i], " \n"[i == n]);
}
int main() {
  init();
  process();
  return 0;
}
