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 

import java.util.*; import java.io.*; import java.math.*;
public class Main{
	static void solve(){//Here is the main function
      int N = nextInt();
      Node[] list = new Node[N];
      UnionFind uf = new UnionFind(N);
      for(int i = 0; i < N; i++){
        list[i] = new Node(i);
      }
      int count = 0;
      ArrayList<Integer> root = new ArrayList<>();
      for(int i = 0; i < N; i++){
        int p = nextInt() - 1;
        if(i != p && uf.isSame(p, i)){
          list[i].parent = i;
        }else{
          uf.doUnion(i, p);
          list[i].parent = p;
          if(i == p){
            root.add(i);
          }
        }
      }
      int r = -1;
      if(root.size() > 0){
        r = root.get(0);
      }
      for(int i = 0; i < N; i++){
        if(list[i].parent == i){
          if(r == -1){
            r = i;
            count++;
          }else{
            if(r != i){
              list[i].parent = r;
              count++;
            }
          }
        }
      }
      myout(count);
      String[] output = new String[N];
      for(int i = 0; i < N; i++){
        output[i] = String.valueOf(list[i].parent + 1);
      }
      myout(myconv(output, 8));
	}
	//Method addition frame start

static class Node{
  int no;
  int parent = -1;
  Node(int no){
    this.no = no;
  }
}

static class UnionFind{
        int[] list;
        int group;
        UnionFind(int size){
                list = new int[size];
                Arrays.fill(list, -1);
                group = size;
        }
        boolean isSame(int L, int R){
                return getRootIndex(L) == getRootIndex(R);
        }
        int getRootIndex(int index){
                if(list[index] < 0){
                        return index;
                }else{
                        list[index] = getRootIndex(list[index]);
                        return list[index];
                }
        }
        void doUnion(int L, int R){
                int Lroot = getRootIndex(L);
                int Rroot = getRootIndex(R);
                if(Lroot != Rroot){
                        group--;
                        if(getSize(Lroot) >= getSize(Rroot)){
                                int tmp = Lroot;
                                Lroot = Rroot;
                                Rroot = tmp;
                        }
                        list[Lroot] += list[Rroot];
                        list[Rroot] = Lroot;
                }
        }
        int getSize(int index){
                return -list[getRootIndex(index)];
        }
        int getGroupCount(){
                return group;
        }
        boolean isRoot(int index){
                return getRootIndex(index) == index;
        }
}
  
	//Method addition frame end

	//Don't have to see. start------------------------------------------
	static class InputIterator{
		ArrayList<String> inputLine = new ArrayList<>(1024);
		int index = 0; int max; String read;
		InputIterator(){
			BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
			try{
				while((read = br.readLine()) != null){
					inputLine.addAll(Arrays.asList(read.split(" ")));
				}
			}catch(IOException e){}
			max = inputLine.size();
		}
		boolean hasNext(){return (index < max);}
		String next(){
			if(hasNext()){
				return inputLine.get(index++);
			}else{
				throw new IndexOutOfBoundsException("There is no more input");
			}
		}
	}
	static HashMap<Integer, String> CONVSTR = new HashMap<>();
	static InputIterator ii = new InputIterator();//This class cannot be used in reactive problem.
	static PrintWriter out = new PrintWriter(System.out);
	static void flush(){out.flush();}
	static void myout(Object t){out.println(t);}
	static void myerr(Object t){System.err.print("debug:");System.err.println(t);}
	static String next(){return ii.next();}
	static boolean hasNext(){return ii.hasNext();}
	static int nextInt(){return Integer.parseInt(next());}
	static long nextLong(){return Long.parseLong(next());}
	static double nextDouble(){return Double.parseDouble(next());}
	static ArrayList<String> nextCharArray(){return myconv(next(), 0);}
	static ArrayList<String> nextStrArray(int size){
		ArrayList<String> ret = new ArrayList<>(size);
		for(int i = 0; i < size; i++){
			ret.add(next());
		}
		return ret;
	}
	static ArrayList<Integer> nextIntArray(int size){
		ArrayList<Integer> ret = new ArrayList<>(size);
		for(int i = 0; i < size; i++){
			ret.add(Integer.parseInt(next()));
		}
		return ret;
	}
	static ArrayList<Long> nextLongArray(int size){
		ArrayList<Long> ret = new ArrayList<>(size);
		for(int i = 0; i < size; i++){
			ret.add(Long.parseLong(next()));
		}
		return ret;
	}
	@SuppressWarnings("unchecked")
	static String myconv(Object list, int no){//only join
		String joinString = CONVSTR.get(no);
		if(list instanceof String[]){
			return String.join(joinString, (String[])list);
		}else if(list instanceof ArrayList){
			return String.join(joinString, (ArrayList)list);
		}else{
			throw new ClassCastException("Don't join");
		}
	}
	static ArrayList<String> myconv(String str, int no){//only split
		String splitString = CONVSTR.get(no);
		return new ArrayList<String>(Arrays.asList(str.split(splitString)));
	}
	public static void main(String[] args){
		CONVSTR.put(8, " "); CONVSTR.put(9, "\n"); CONVSTR.put(0, "");
		solve();flush();
	}
	//Don't have to see. end------------------------------------------
}