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#include "bits/stdc++.h" // Tomasz Nowak
using namespace std;     // XIII LO Szczecin
using LL = long long;    // Poland
#define FOR(i, l, r) for(int i = (l); i <= (r); ++i)
#define REP(i, n) FOR(i, 0, (n) - 1)
template<class T> int size(T &&x) {
	return int(x.size());
}
template<class A, class B> ostream& operator<<(ostream &out, const pair<A, B> &p) {
	return out << '(' << p.first << ", " << p.second << ')';
}
template<class T> auto operator<<(ostream &out, T &&x) -> decltype(x.begin(), out) {
	out << '{';
	for(auto it = x.begin(); it != x.end(); ++it)
		out << *it << (it == prev(x.end()) ? "" : ", ");
	return out << '}';
}
void dump() {}
template<class T, class... Args> void dump(T &&x, Args... args) {
	cerr << x << ";  ";
	dump(args...);
}
#ifdef DEBUG
  struct Nl{~Nl(){cerr << '\n';}};
# define debug(x...) cerr << (strcmp(#x, "") ? #x ":  " : ""), dump(x), Nl(), cerr << ""
#else
# define debug(...) 0 && cerr
#endif
mt19937_64 rng(0);
int rd(int l, int r) {
	return uniform_int_distribution<int>(l, r)(rng);
}
// end of templates

LL answer = 0;

struct Node {
	int root = -1;
	array<int, 2> interval = {-1, -1};
	array<int, 2> endpath = {-1, -1};

	bool has_child(bool c) {
		return interval[c] != root or endpath[c] != -1;
	}

	void reroot(int v) {
		assert(interval[0] <= v and v <= interval[1]);
		answer += abs(root - v);
		root = v;
	}
} empty_node;
ostream& operator<<(ostream &o, Node &n) {
	return o << vector{n.interval[0], n.root, n.interval[1], n.endpath[0], n.endpath[1]};
}
bool operator==(Node a, Node b) {
	return a.root == b.root and a.interval == b.interval and a.endpath == b.endpath;
}

void merge_down(vector<Node> &tree, int v, bool side) {
	debug(tree);
	int w = tree[v].endpath[side];
	assert(w != -1 and not tree[w].has_child(not side));
	assert(abs(tree[v].interval[side] - tree[w].root) == 1);
	tree[v].interval[side] = tree[w].interval[side];
	tree[v].endpath[side] = tree[w].endpath[side];
	tree[w] = empty_node;
}

void disappear_subtree(vector<Node> &tree, int root, bool side_rm) {
	debug(root, side_rm);
	tree[root].reroot(tree[root].interval[side_rm]);
	while(tree[root].has_child(side_rm)) {
		int son_rm = tree[root].endpath[side_rm];
		disappear_subtree(tree, son_rm, not side_rm);
		merge_down(tree, root, side_rm);
		tree[root].reroot(tree[root].interval[side_rm]);
	}
}

int retrieve_child(vector<Node> &tree, int root, bool side) {
	if(tree[root].root == tree[root].interval[side])
		return tree[root].endpath[side];
	debug(root, side) << "retrieve";
	int n = size(tree);
	tree.emplace_back(empty_node);
	int w = tree[root].root + (side == 0 ? -1 : 1);
	debug(root, w);
	tree[n].endpath[side] = tree[root].endpath[side];
	tree[root].endpath[side] = n;
	tree[n].root = w;
	tree[n].interval = {w, w};
	tree[n].interval[side] = tree[root].interval[side];
	tree[root].interval[side] = tree[root].root;
	return n;
}

bool intersects(array<int, 2> &a, array<int, 2> &b) {
	return min(a[1], b[1]) - max(a[0], b[0]) >= 0;
}

void solve(vector<Node> *tree1, vector<Node> *tree2, int r1, int r2) {
	debug(r1, r2);
	debug(*tree1, *tree2) << "starting moving root";
	if(r1 == -1 and r2 == -1)
		return;
	assert(r1 != -1 and r2 != -1);
	auto fix_root = [&] {
		auto it1 = (*tree1)[r1].interval, it2 = (*tree2)[r2].interval;
		if(intersects(it1, it2)) {
			int mid1 = (*tree1)[r1].root,
				mid2 = (*tree2)[r2].root;
			debug(it1, mid1, it2, mid2);
			vector<int>  candidates = {max(it1[0], it2[0]), min(it1[1], it2[1]), mid1, mid2};
			for(int c : candidates)
				if(max(it1[0], it2[0]) <= c and c <= min(it1[1], it2[1]) and
						min(mid1, mid2) <= c and c <= max(mid1, mid2)) {
					(*tree1)[r1].reroot(c);
					(*tree2)[r2].reroot(c);
					return;
				}
			assert(false);
		}
		if(it1[1] < it2[0]) {
			swap(r1, r2);
			swap(it1, it2);
			swap(tree1, tree2);
		}
		vector<Node> &t1 = *tree1, &t2 = *tree2;
		debug(t1[r1].interval, t2[r2].interval) << "START";

		while(t2[r2].root < t1[r1].interval[0]) {
			// t1[r1].reroot(t1[r1].interval[0]);
			disappear_subtree(t1, t1[r1].endpath[0], 1);
			merge_down(t1, r1, 0);
		}
		debug(t1[r1].interval, t2[r2].interval, t2[r2].root) << "END";
		t1[r1].reroot(t2[r2].root);
	};
	fix_root();

	vector<Node> &t1 = *tree1, &t2 = *tree2;
	debug(t1, t2) << "finished moving root";
	for(int c : {0, 1})
		solve(tree1, tree2, retrieve_child(t1, r1, c), retrieve_child(t2, r2, c));
}

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);

	int n;
	cin >> n;
	auto input_tree = [&] {
		vector<Node> ret(n);
		int root = -1;
		REP(v, n) {
			ret[v].root = v;
			ret[v].interval = {v, v};
			int p;
			cin >> p;
			if(p == -1)
				root = v;
			else {
				--p;
				ret[p].endpath[bool(p < v)] = v;
			}
		}
		return make_pair(ret, root);
	};
	auto [tree1, root1] = input_tree();
	auto [tree2, root2] = input_tree();
	debug(tree1, tree2);

	solve(&tree1, &tree2, root1, root2);
	debug(tree1, tree2);
	cout << answer << '\n';
}