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.
// package stupiddog;

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

/**
 *
 * @author Huynh Sam Ha - BKU - VN - 1610852@hcmut.edu.vn
 * @author Stupid - Dog
 *
 */
public class StupidDog {

    public static void main(String[] args) throws IOException {
        inputSystem = new InputStreamReader(System.in);
        outputSystem = new OutputStreamWriter(System.out);
        //inputFile = new FileReader("D:/Java/File/inp.txt");
        //outputFile = new FileWriter("D:/Java/File/out.txt");

        inp = new BufferedReader(inputSystem);
        out = new PrintWriter(outputSystem);
        
        solve();
        
        inp.close();
        out.close();
    }

    static int n, p[], b[], dd[];
    static List<Integer> a[];
    
    static void solve() throws IOException {
        n = nextInt(); 
        p = new int[n+1];
        b = new int[n+1];
        a = new ArrayList[n+1];
        for (int i=1;i<=n;i++) a[i] = new ArrayList<Integer>();
        for (int i = 1; i <= n; i++) {
            p[i] = nextInt();
            a[i].add(p[i]); 
        }
        for (int i = 1; i <= n; i++) {
            b[i] = nextInt();
            b[0] += b[i];
        }
        
        int cnt = 0;
        dd = new int[n+1];
        for (int u = 1; u <= n; u++) {
            if (dd[u] == 0) {
                cnt++; dfs(u);
            }
        }
        
        int ans = cnt == 1 ? 0 : cnt;
        ans += b[0] % 2 == 0 ? 1 : 0;
        out.println(ans);
    }   

    static Deque<Integer> st = new LinkedList<Integer>();
    static void dfs(int u) {
        st.clear(); st.add(u); dd[u] = 1;
        while (!st.isEmpty()) {
            u = st.pop();
            for (Integer v : a[u]) {
                if (dd[v] == 0) {
                    dd[v] = 1; st.push(v);
                }
            }
        }
    }
    
    /* ---------------------------------------------------- */
    static BufferedReader inp;
    static PrintWriter out;
    static InputStreamReader inputSystem;
    static OutputStreamWriter outputSystem;
    static Reader inputFile;
    static Writer outputFile;
    static StringTokenizer token;

    /*NSt + TAB*/
    static String nextString() throws IOException {
        while (token == null || !token.hasMoreElements()) {
            token = new StringTokenizer(inp.readLine());
        }
        return token.nextToken();
    }

    /*NI + TAB*/
    static int nextInt() throws IOException {
        return Integer.parseInt(nextString());
    }

    /*NL + TAB*/
    static long nextLong() throws IOException {
        return Long.parseLong(nextString());
    }

    /*NDB + TAB*/
    static double nextDouble() throws IOException {
        return Double.parseDouble(nextString());
    }
}

/**
 * 
 * TAB 
 * out.println(); outln 
 * out.printf(""); outf
 * 
 * for1n
 */
