#include <bits/stdc++.h>
using namespace std;
template <class T>
inline void rread(T& num) {
  num = 0;
  T f = 1;
  char ch = getchar();
  while (ch < '0' || ch > '9') {
    if (ch == '-') f = -1;
    ch = getchar();
  }
  while (ch >= '0' && ch <= '9') num = num * 10 + ch - '0', ch = getchar();
  num *= f;
}
const int inf = 2e9, mod = 1e9 + 7;
const int maxn = 2e5 + 10;
const long double PI = acos(-1.0);
long long gcd(long long a, long long b) { return (a ? gcd(b % a, a) : b); }
long long power(long long a, long long n) {
  long long p = 1;
  while (n > 0) {
    if (n % 2) {
      p = p * a;
    }
    n >>= 1;
    a *= a;
  }
  return p;
}
long long power(long long a, long long n, long long mod) {
  long long p = 1;
  while (n > 0) {
    if (n % 2) {
      p = p * a;
      p %= mod;
    }
    n >>= 1;
    a *= a;
    a %= mod;
  }
  return p % mod;
}
int n, m;
int a[maxn];
vector<int> huan, dan;
vector<int> nex[maxn];
int flag[maxn];
void dfs(int x, int be) {
  flag[x] = 1;
  int cun = 0;
  for (int i = 0; i < nex[x].size(); i++)
    if (nex[x][i] == be)
      cun++;
    else {
      if (flag[nex[x][i]] == 1) {
        if (nex[x][i] == x)
          dan.push_back(nex[x][i]);
        else
          huan.push_back(nex[x][i]);
        continue;
      }
      dfs(nex[x][i], x);
    }
  if (cun >= 2) huan.push_back(x);
}
int main() {
  while (~scanf("%d", &n)) {
    for (int i = 1; i <= n; i++) nex[i].clear();
    for (int i = 1; i <= n; i++) {
      scanf("%d", &a[i]);
      nex[i].push_back(a[i]);
      if (a[i] != i) nex[a[i]].push_back(i);
    }
    huan.clear();
    dan.clear();
    memset(flag, 0, sizeof flag);
    for (int i = 1; i <= n; i++)
      if (flag[i] == 0) {
        dfs(i, -1);
      }
    if (dan.size() >= 1) {
      cout << huan.size() / 2 + dan.size() - 1 << endl;
      for (int i = 0; i < huan.size(); i += 2) a[huan[i]] = dan[dan.size() - 1];
      for (int i = 0; i < dan.size() - 1; i++) a[dan[i]] = dan[dan.size() - 1];
      for (int i = 1; i <= n; i++) cout << a[i] << " ";
      cout << endl;
    } else {
      cout << huan.size() / 2 << endl;
      for (int i = 0; i < huan.size(); i += 2)
        a[huan[i]] = huan[huan.size() - 2];
      for (int i = 1; i <= n; i++) cout << a[i] << " ";
      cout << endl;
    }
  }
  return 0;
}
