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.io.*;
import java.util.Arrays;
import java.util.StringTokenizer;

import static java.lang.Math.min;


public class Solution {
    private static String inputFilename = "src/input.txt";
    private static String outputFilename = "src/output.txt";
    private BufferedReader in;
    private StringTokenizer line;
    private PrintWriter out;
    private boolean isDebug;

    public Solution(boolean isDebug) {
        this.isDebug = isDebug;
    }

    public void solve() throws IOException {
        int n = nextInt();
        int[] a = nextIntArray(n);
        int[] b = nextIntArray(n);
        int s = 0;
        for (int i = 0; i < n; i++) {
            a[i]--;
            s += b[i];
        }
        int cnt = 0;
        for (int i = 0; i < n; i++) {
            if (a[i] != -1) {
                cnt++;
                int cr = i;
                while (a[cr] != -1) {
                    int pr = cr;
                    cr = a[cr];
                    a[pr] = -1;
                }
            }
        }
        out.println((cnt == 1 ? 0 : cnt) + (1 - s % 2));
    }

    private static final int mm = 1000000007;

    private long mult(long a, long b) {
        return a * b % mm;
    }

    public static void main(String[] args) throws IOException {
        new Solution(Arrays.asList(args).contains("DEBUG_MODE")).run(args);
    }

    public void run(String[] args) throws IOException {
        if (isDebug) {
            in = new BufferedReader(new InputStreamReader(new FileInputStream(inputFilename)));
//            in = new BufferedReader(new InputStreamReader(System.in));
        } else {
            in = new BufferedReader(new InputStreamReader(System.in));
        }
        out = new PrintWriter(System.out);
//        out = new PrintWriter(outputFilename);

//        int t = nextInt();
        int t = 1;
        for (int i = 0; i < t; i++) {
//            out.print("Case #" + (i + 1) + ": ");
            solve();
        }

        in.close();
        out.flush();
        out.close();
    }

    private int[] nextIntArray(int n) throws IOException {
        int[] res = new int[n];
        for (int i = 0; i < n; i++) {
            res[i] = nextInt();
        }
        return res;
    }

    private long[] nextLongArray(int n) throws IOException {
        long[] res = new long[n];
        for (int i = 0; i < n; i++) {
            res[i] = nextInt();
        }
        return res;
    }

    private int nextInt() throws IOException {
        return Integer.parseInt(nextToken());
    }

    private long nextLong() throws IOException {
        return Long.parseLong(nextToken());
    }

    private double nextDouble() throws IOException {
        return Double.parseDouble(nextToken());
    }

    private String nextToken() throws IOException {
        while (line == null || !line.hasMoreTokens()) {
            line = new StringTokenizer(in.readLine());
        }
        return line.nextToken();
    }
}