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.io.*;
import java.util.*;

public class Solution {

	public static void main(String[] args) throws IOException {
		InputStream inputStream = System.in;
		OutputStream outputStream = System.out;
		InputReader in = new InputReader(inputStream);
		OutputWriter out = new OutputWriter(outputStream);
		Task task = new Task();
		int t = 1;
		for (int i = 1; i <= t; i++) task.solve(i, in, out);
		out.close();
	}

	static class Task {
 		
		public void solve(int testNumber, InputReader in, OutputWriter out) throws IOException {
			int n = in.nextInt();
			int[] arr = in.nextIntArray(n + 1, 1);
			boolean[] s = new boolean[n + 1];
			DSU dsu = new DSU(n + 1);
			int[] cpy = Arrays.copyOf(arr, n + 1);
			for (int i = 1; i <= n; i++) {
				if (i == arr[i]) continue;
				int c = dsu.cal;
				dsu.union(i, arr[i]);
				if (c == dsu.cal) {
					arr[i] = i;
					s[i] = true;
				}
			}
			int r = -1;
			for (int i = 1; i <= n; i++) 
				if (arr[i] == i) {
					r = i;
					if (!s[i]) break;
				}
			for (int i = 1; i <= n; i++)
				if (arr[i] == i) arr[i] = r;
			int cnt = 0;
			for (int i = 1; i <= n; i++)
				if (arr[i] != cpy[i]) cnt++;
			out.println(cnt, "\n");
			out.printIntArray(arr, 1, n + 1);
 		}
	}
	
	static class DSU {
		int[] par, size, rank;
		boolean[] valid;
		int n, cal;
		
		public DSU(int n) {
			this.n = n;
			init(n);
		}
		
		public void init(int n) {
			par = new int[n];
			size = new int[n];
			rank = new int[n];
			valid = new boolean[n];
			cal = n;
			for (int i = 0; i < n; i++) {
				par[i] = i;
				size[i] = 1;
			}
		}
		
		public boolean isValid(int x) {
			return valid[x];
		}
		
		public int find(int x) {
			if (par[x] != x) return par[x] = find(par[x]);
			return par[x];
		}
		
		public boolean isSame(int x, int y) {
			return find(x) == find(y);
		}
		
		public void union(int x, int y) {
			x = find(x);
			y = find(y);
			if (x == y) {
				valid[x] = true;
				return;
			}
			size[x] = size[y] = size[x] + size[y];
			valid[x] = valid[y] = valid[x] | valid[y];
			if (rank[x] < rank[y]) par[x] = y;
			else par[y] = x;
			if (rank[x] == rank[y]) rank[x]++;
			cal--;
		}
		
		public int getSize(int x) {
			return size[find(x)];
		}
	}

	static class InputReader {
		private BufferedReader reader;
		private StringTokenizer tokenizer;

		public InputReader(InputStream stream) {
			reader = new BufferedReader(new InputStreamReader(stream), 32768);
			tokenizer = null;
		}
		
		private void tokenize() {
			while (tokenizer == null || !tokenizer.hasMoreTokens()) {
				try {
					tokenizer = new StringTokenizer(reader.readLine());
				} catch (IOException e) {
					throw new RuntimeException(e);
				}
			}
		}

		public String next() {
			tokenize();
			return tokenizer.nextToken();
		}

		public int nextInt() {
			return Integer.parseInt(next());
		}

		public long nextLong() {
			return Long.parseLong(next());
		}
		
		public char nextChar() {
			return next().charAt(0);
		}
		
		public float nextFloat() {
			return Float.parseFloat(next());
		}
		
		public double nextDouble() {
			return Double.parseDouble(next());
		}

		public int[] nextIntArray(int size, int a) {
			tokenize();
			int[] arr=new int[size];
			for(int i = a; i < size; i++) {
				tokenize();
				arr[i] = Integer.parseInt(tokenizer.nextToken());
			}
			return arr;
		}
		
		public long[] nextLongArray(int size, int a) {
			tokenize();
			long[] arr=new long[size];
			for(int i = a; i < size; i++) {
				tokenize();
				arr[i] = Long.parseLong(tokenizer.nextToken());
			}
			return arr;
		}
		
		public float[] nextFloatArray(int size, int a) {
			tokenize();
			float[] arr=new float[size];
			for(int i = a; i < size; i++) {
				tokenize();
				arr[i] = Float.parseFloat(tokenizer.nextToken());
			}
			return arr;
		}

		public double[] nextDoubleArray(int size, int a) {
			tokenize();
			double[] arr=new double[size];
			for(int i = a; i < size; i++) {
				tokenize();
				arr[i] = Double.parseDouble(tokenizer.nextToken());
			}
			return arr;
		}

		public String[] nextStringArray(int size, int a) throws IOException {
			String[] arr=new String[size];
			for(int i = a; i < size; i++) 
				arr[i] = reader.readLine();
			return arr;
		}

		public char[] nextCharArray(int size) throws IOException {
			return reader.readLine().toCharArray();
		}
	}

	static class OutputWriter {
		public PrintWriter pw;

		public OutputWriter(OutputStream stream) {
			pw = new PrintWriter(stream);
		}
		
		public void println(Object... obj) {
			if (obj.length == 0) pw.println();
			else {
				String delimiter = (String) obj[obj.length - 1];
				for (int i = 0 ; i < obj.length - 1; i++) pw.print(obj[i] + delimiter);
			}
		}

		public void close() {
			pw.close();
		}

		public void flush() {
			pw.flush();
		}

		public void printStringArray(String[] arr, int a, int b) {
			for(int i = a; i < b; i++)
				pw.println(arr[i]);
		}
		
		public void printBooleanArray(boolean[] arr, int a, int b) {
			for(int i = a; i < b; i++)
				pw.print(arr[i] + " ");
		}

		public void printIntArray(int[] arr, int a, int b) {
			for(int i = a; i < b; i++)
				pw.print(arr[i] + " ");
		}

		public void printLongArray(long[] arr, int a, int b) {
			for(int i = a; i < b; i++)
				pw.print(arr[i] + " ");
		}

		public void printCharArray(char[] arr, int a, int b) {
			for(int i = a; i < b; i++)
				pw.print(arr[i] + " ");
		}

		public void printFloatArray(float[] arr, int a, int b) {
			for(int i = a; i < b; i++)
				pw.print(arr[i] + " ");
		}

		public void printDoubleArray(double[] arr, int a, int b) {
			for(int i = a; i < b; i++)
				pw.print(arr[i] + " ");
		}
		
		public void printIntArrayList(ArrayList<Integer> arr, int a, int b) {
			for(int i = a; i < b; i++)
				pw.print(arr.get(i) + " ");
		}
		
		public void printLongArrayList(ArrayList<Long> arr, int a, int b) {
			for(int i = a; i < b; i++)
				pw.print(arr.get(i) + " ");
		}
	}
}