#include <bits/stdc++.h>
using namespace std;

// =====================================================================================
// === Segment Tree
// =====================================================================================
class SegmentTree {
	public:
	int size_ = 1;
	vector<pair<int, int>> dat;
	vector<int> laz;

	pair<int, int> merge(pair<int, int> v1, pair<int, int> v2) {
		if (v1.first < v2.first) return v1;
		if (v1.first > v2.first) return v2;
		return make_pair(v1.first, v1.second + v2.second);
	}

	void init(int sz) {
		while (size_ <= sz) size_ *= 2;
		dat.resize(size_ * 2, make_pair(0, 0));
		laz.resize(size_ * 2, 0);
		for (int i = 0; i < sz; i++) {
			int cx = size_ + i;
			dat[cx].second = 1;
			while (cx >= 2) {
				cx >>= 1;
			}
		}
	}
	
	void refresh(int pos) {
		if (pos < size_) {
			laz[pos * 2 + 0] += laz[pos];
			laz[pos * 2 + 1] += laz[pos];
			laz[pos] = 0;
			pair<int, int> v1 = make_pair(dat[pos * 2 + 0].first + laz[pos * 2 + 0], dat[pos * 2 + 0].second);
			pair<int, int> v2 = make_pair(dat[pos * 2 + 1].first + laz[pos * 2 + 1], dat[pos * 2 + 1].second);
			dat[pos] = merge(v1, v2);
		}
		else {
			dat[pos].first += laz[pos];
			laz[pos] = 0;
		}
	}
	
	void add_(int l, int r, int x, int a, int b, int u) {
		if (l <= a && b <= r) { laz[u] += x; return; }
		if (r <= a || b <= l) return;
		refresh(u);
		add_(l, r, x, a, (a + b) / 2, u * 2);
		add_(l, r, x, (a + b) / 2, b, u * 2 + 1);
		refresh(u);
	}

	void add(int l, int r, int x) {
		add_(l, r, x, 0, size_, 1);
	}
	
	pair<int, int> query_(int l, int r, int a, int b, int u) {
		if (l <= a && b <= r) { refresh(u); return dat[u]; }
		if (r <= a || b <= l) return make_pair((1 << 30), 0);
		refresh(u);
		pair<int, int> v1 = query_(l, r, a, (a + b) / 2, u * 2);
		pair<int, int> v2 = query_(l, r, (a + b) / 2, b, u * 2 + 1);
		refresh(u);
		return merge(v1, v2);
	}

	pair<int, int> query(int l, int r) {
		return query_(l, r, 0, size_, 1);
	}
};

class SegmentTree2 {
	public:
	vector<int> dat;

	void init(int sz) {
		dat.resize(sz, 0);
	}

	void add(int l, int r, int x) {
		for (int i = l; i < r; i++) dat[i] += x;
	}

	pair<int, int> query(int l, int r) {
		int minv = (1 << 30);
		int cnt = 0;
		for (int i = l; i < r; i++) {
			if (minv > dat[i]) { minv = dat[i]; cnt = 0; }
			if (minv == dat[i]) cnt += 1;
		}
		return make_pair(minv, cnt);
	}
};

// =====================================================================================
// === Main Function
// =====================================================================================
int N;
int U[1 << 19], V[1 << 19];
int P[1 << 19], InvP[1 << 19];
vector<int> E[1 << 19];

int main() {
	// Step 1. input
	scanf("%d", &N);
	for (int i = 1; i <= N - 1; i++) scanf("%d%d", &U[i], &V[i]);
	for (int i = 1; i <= N; i++) scanf("%d", &P[i]);
	for (int i = 1; i <= N; i++) InvP[P[i]] = i;
	for (int i = 1; i <= N - 1; i++) U[i] = InvP[U[i]];
	for (int i = 1; i <= N - 1; i++) V[i] = InvP[V[i]];

	// Step 2. Solve Init
	SegmentTree Z; Z.init(N + 2);
	for (int i = 1; i <= N - 1; i++) {
		if (U[i] > V[i]) swap(U[i], V[i]);
		E[V[i]].push_back(U[i]);
	}

	// Step 3. Solve
	long long ans = 0;
	for (int i = 1; i <= N; i++) {
		Z.add(1, i + 1, 1);
		for (int idx : E[i]) Z.add(1, idx + 1, -1);
		pair<int, int> v = Z.query(1, i + 1);
		if (v.first == 1) ans += 1LL * v.second;
	}
	cout << ans << endl;
	return 0;
}