#include <bits/stdc++.h>
using namespace std;
const int MOD = 1e9 + 7;
int a[200001];
int visited[200001];
vector<long long> fixedpt;
vector<long long> repair;
bool empt;
void dfs(int u) {
  visited[u] = 2;
  int v = a[u];
  if (v == u) {
  } else if (visited[v] == 2) {
    repair.push_back(v);
  } else if (visited[v] == 1) {
  } else {
    dfs(v);
  }
  visited[u] = 1;
}
int main() {
  int n;
  int cnt = 0;
  scanf("%d", &n);
  for (int i = 0; i < n; i++) {
    scanf("%d", &a[i]);
    a[i]--;
    if (a[i] == i) fixedpt.push_back(i);
  }
  empt = false;
  if (fixedpt.empty()) empt = true;
  if (!fixedpt.empty()) {
    for (int i = 0; i < fixedpt.size(); i++) {
      a[fixedpt[i]] = fixedpt[0];
      if (i > 0) cnt++;
    }
  }
  for (int i = 0; i < n; i++) {
    if (!visited[i]) dfs(i);
  }
  for (int i = 0; i < repair.size(); i++) {
    if (fixedpt.empty()) {
      a[repair[i]] = repair[0];
    } else {
      a[repair[i]] = fixedpt[0];
    }
    cnt++;
  }
  printf("%d\n", cnt);
  for (int i = 0; i < n; i++) {
    printf("%d ", a[i] + 1);
  }
}
