Pavel cooks barbecue. There are n skewers, they lay on a brazier in a row, each on one of n positions. Pavel wants each skewer to be cooked some time in every of n positions in two directions: in the one it was directed originally and in the reversed direction.

Pavel has a plan: a permutation p and a sequence b1, b2, ..., bn, consisting of zeros and ones. Each second Pavel move skewer on position i to position pi, and if bi equals 1 then he reverses it. So he hope that every skewer will visit every position in both directions.

Unfortunately, not every pair of permutation p and sequence b suits Pavel. What is the minimum total number of elements in the given permutation p and the given sequence b he needs to change so that every skewer will visit each of 2n placements? Note that after changing the permutation should remain a permutation as well.

There is no problem for Pavel, if some skewer visits some of the placements several times before he ends to cook. In other words, a permutation p and a sequence b suit him if there is an integer k (k ≥ 2n), so that after k seconds each skewer visits each of the 2n placements.

It can be shown that some suitable pair of permutation p and sequence b exists for any n.

Input

The first line contain the integer n (1 ≤ n ≤ 2·105) — the number of skewers.

The second line contains a sequence of integers p1, p2, ..., pn (1 ≤ pi ≤ n) — the permutation, according to which Pavel wants to move the skewers.

The third line contains a sequence b1, b2, ..., bn consisting of zeros and ones, according to which Pavel wants to reverse the skewers.

Output

Print single integer — the minimum total number of elements in the given permutation p and the given sequence b he needs to change so that every skewer will visit each of 2n placements.

Examples

Input

4
4 3 2 1
0 1 1 1


Output

2


Input

3
2 3 1
0 0 0


Output

1

Note

In the first example Pavel can change the permutation to 4, 3, 1, 2.

In the second example Pavel can change any element of b to 1.
import java.awt.Point;
import java.io.*;
import java.lang.reflect.Array;
import java.util.*;
import java.util.Map.Entry;

public class Geometry {

	static final boolean ONLINE_JUDGE = System.getProperty("ONLINE_JUDGE") != null;

	public static void main(String[] args) {
		new Geometry().run();
	}

	BufferedReader in;
	PrintWriter out;
	StringTokenizer tok;

	int maxA(int[] a) {
		int max = Integer.MIN_VALUE;
		for (int i = 0; i < a.length; i++) {
			if (a[i] > max) {
				max = a[i];

			}
		}
		return max;
	}

	int minA(int[] a) {
		int min = Integer.MAX_VALUE;
		for (int i = 0; i < a.length; i++) {
			if (a[i] < min) {
				min = a[i];

			}
		}
		return min;
	}

	void init() throws FileNotFoundException {

		if (ONLINE_JUDGE) {
			in = new BufferedReader(new InputStreamReader(System.in));
			out = new PrintWriter(System.out);
		} else {
			in = new BufferedReader(new FileReader("input.txt"));
			out = new PrintWriter("output.txt");
		}

		tok = new StringTokenizer("");
	}

	void run() {
		try {
			long timeStart = System.currentTimeMillis();

			init();
			solve();

			out.close();

			long timeEnd = System.currentTimeMillis();
			System.err.println("Time = " + (timeEnd - timeStart) + " COMPILED");
		} catch (Exception e) {
			e.printStackTrace();
			System.exit(-1);
		}
	}

	long memoryTotal, memoryFree;

	void memory() {
		memoryFree = Runtime.getRuntime().freeMemory();
		System.err.println("Memory = " + ((-memoryTotal + memoryFree) >> 10) + " KB");
	}

	String readLine() throws IOException {
		return in.readLine();
	}

	String delimiter = " ";

	String rS() throws IOException {
		while (!tok.hasMoreTokens()) {
			String nextLine = readLine();
			if (null == nextLine)
				return null;

			tok = new StringTokenizer(nextLine);
		}

		return tok.nextToken(delimiter);
	}

	int[] rA(int b) {
		int a[] = new int[b];
		for (int i = 0; i < b; i++) {
			try {
				a[i] = rI();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
		return a;
	}

	int rI() throws IOException {
		return Integer.parseInt(rS());
	}

	long rL() throws IOException {
		return Long.parseLong(rS());
	}

	void sort(int[] a) {
		Integer arr[] = new Integer[a.length];
		for (int i = 0; i < a.length; i++) {
			arr[i] = a[i];
		}
		Arrays.sort(arr);
		for (int i = 0; i < a.length; i++) {
			a[i] = arr[i];
		}
	}

	void initGraph(int a) {
		for (int i = 0; i < a; i++) {
			graph[i] = new ArrayList<Integer>();
		}
	}

	List<Integer> graph[];

	void solve() throws IOException {
		int n = rI();
		this.graph = new List[n];
		initGraph(n);
		this.used = new boolean[n];
		int ans = 0;
		for (int i = 0; i < n; i++) {
			int a = rI();
			graph[i].add(a - 1);
		}
		int[] b = rA(n);
		int flag = 0;
		for (int i = 0; i < n; i++) {
			flag += b[i];
		}
		for (int i = 0; i < n; i++) {
			if (!used[i]) {
				dfs(i);
				ans++;
			}
		}
		out.println(ans > 1 ? ans+1-flag%2 : 1-flag%2);
	}

	boolean[] used;

	void dfs(int from) {
		used[from] = true;
		for (int i : graph[from]) {
			if (!used[i]) {
				dfs(i);
			}
		}
	}
}
