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.*;

public class Main {
	public static void main(String arg[])throws Exception{
		Scanner sc = new Scanner(System.in);
		BufferedWriter wff = new BufferedWriter(new OutputStreamWriter(System.out));
		
		int n = sc.nextInt();
			
		int[] arr = new int[n];
		
		for(int i = 0; i < n; i++)
			arr[i] = sc.nextInt() - 1;
		
		int s = 0;
		
		for(int i = 0; i < n; i++)
			s += sc.nextInt();
		
		int res = 0;		
		
		boolean[] marcado = new boolean[n];
		
		for(int i = 0; i < n; i++){
			if(!marcado[i]){
				res++;
				int pos = i;
				while(!marcado[pos]){
					marcado[pos] = true;
					pos = arr[pos];
				}
			}
		}
		
		if(res == 1)
			res--;
		
		if(s % 2 == 0)
			res++;
		
		wff.write("" + res);
		wff.newLine();
		wff.flush();
	}
}
