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;
template <class T>
inline void read(T& num) {
  bool start = false, neg = false;
  char c;
  num = 0;
  while ((c = getchar()) != EOF) {
    if (c == '-')
      start = neg = true;
    else if (c >= '0' && c <= '9') {
      start = true;
      num = num * 10 + c - '0';
    } else if (start)
      break;
  }
  if (neg) num = -num;
}
const int maxn = (int)(2e5) + 5;
int fa[maxn], a[maxn], rk[maxn];
int vis[maxn];
int top = 0;
int Find(int x) { return fa[x] == x ? x : fa[x] = Find(fa[x]); }
bool cmp(int i, int j) { return vis[i] > vis[j]; }
int main() {
  int n, cnt = 0;
  read(n);
  for (int i = (1); i <= (n); i++) read(a[i]), fa[i] = rk[i] = i;
  for (int i = (1); i <= (n); i++) {
    if (i == a[i]) {
      if (cnt == 0) {
        cnt = 1;
        continue;
      }
    }
    int x = Find(i), y = Find(a[i]);
    if (x == y)
      vis[i] = 1, ++top;
    else
      fa[x] = y;
  }
  printf("%d\n", top);
  sort(rk + 1, rk + n + 1, cmp);
  int p = 1;
  for (int i = (1); i <= (n); i++)
    if (vis[rk[i]]) {
      if (p <= n && Find(rk[i]) == Find(rk[p])) p++;
      a[rk[i]] = rk[p];
      fa[rk[i]] = rk[p];
    }
  for (int i = (1); i <= (n); i++) printf("%d ", a[i]);
  putchar('\n');
  return 0;
}
