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#include<iostream>
#include<vector>
#include<queue>
#include<string>
#include<map>

using namespace std;

class node{
    
    public:
        int parent=0;
        int left = -1;
        int right = -1;
};

class bst{
    public:
        vector<node> nodes;
        
    bst(int n){
        nodes = vector<node>(n);
    }
    
    bool can_left_rotate(int n){
        if(nodes[n].right != -1){
            if(nodes[nodes[n].right].left == -1){
                return true;
            } 
        }
        
        return false;
    }
    
    bool can_right_rotate(int n){
        if(nodes[n].left != -1){
            if(nodes[nodes[n].left].right == -1){
                return true;
            }
        }
        
        return false;
    }
    
    void left_rotate(int n){
        if(nodes[n].parent != -1){
            if(nodes[nodes[n].parent].right == n){
                nodes[nodes[n].parent].right = nodes[n].right;
            }else{
                nodes[nodes[n].parent].left = nodes[n].right;
            }
        }
        nodes[nodes[n].right].parent = nodes[n].parent;
        nodes[n].parent = nodes[n].right;
        nodes[nodes[n].parent].left = n;
        nodes[n].right = -1;
    }
    
    void right_rotate(int n){
        if(nodes[n].parent != -1){
            if(nodes[nodes[n].parent].right == n){
                nodes[nodes[n].parent].right = nodes[n].left;
            }else{
                nodes[nodes[n].parent].left = nodes[n].left;
            }
        }
        nodes[nodes[n].left].parent = nodes[n].parent;
        nodes[n].parent = nodes[n].left;
        nodes[nodes[n].parent].right = n;
        nodes[n].left = -1;
    }
    
    bool compare_bst(bst tree){
        for(int i=0; i<this->nodes.size(); i++){
            if(this->nodes[i].parent != tree.nodes[i].parent)
                return false;
        }
        return true;
    }
      
    
};

int bfs(bst first_tree, bst second_tree, int n){
    queue<bst> Q;
    queue<int> D;

    Q.push(first_tree);
    D.push(0);

    string visit="";
    for(int i=0; i<n; i++){
        visit += first_tree.nodes[i].parent;
    }
    
    map<string, bool> visited;
    
    visited[visit] = true;
    
    while(!Q.empty()){
        
        bst cur_bst(n);
        int cur_d;
        
        cur_bst = Q.front();
        cur_d = D.front();
        
        Q.pop();
        D.pop();
        
        
        
        if(cur_bst.compare_bst(second_tree)){
            return cur_d;
        }else{
            for(int i=0; i<cur_bst.nodes.size(); i++){
                if(cur_bst.can_left_rotate(i)){
                    bst next_bst = cur_bst;
                    next_bst.left_rotate(i);
                    
                    string visit="";
                    for(int i=0; i<n; i++){
                        visit += next_bst.nodes[i].parent;
                    }
                    
                    if(visited[visit]==false){
                        visited[visit] = true;
                        Q.push(next_bst);
                        D.push(cur_d+1);
                    }
                    
                }
                if(cur_bst.can_right_rotate(i)){
                    bst next_bst = cur_bst;
                    next_bst.right_rotate(i);
                    
                    string visit="";
                    for(int i=0; i<n; i++){
                        visit += next_bst.nodes[i].parent;
                    }
                    
                    if(visited[visit]==false){
                        visited[visit] = true;
                        Q.push(next_bst);
                        D.push(cur_d+1);
                    }
                    
                    
                }
            }
        }
    }
}


int main(){
    int n;
    cin >> n;
    
    bst first_tree(n);
    bst second_tree(n);
    
    for(int i=0; i<n; i++){
        int p;
        cin >> p;
        if(p>0){
            p--;
        }
        first_tree.nodes[i].parent = p;
        if(p!=-1){
            if(p<i){
                first_tree.nodes[p].right = i;
            }else{
                first_tree.nodes[p].left = i;
            }
        }
        
    }
    
    for(int i=0; i<n; i++){
        int p;
        cin >> p;
        if(p>0){
            p--;
        }
        second_tree.nodes[i].parent = p;
        if(p!=-1){
            if(p<i){
                second_tree.nodes[p].right = i;
            }else{
                second_tree.nodes[p].left = i;
            }
        }
    }
    
    cout << bfs(first_tree, second_tree, n);
}