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

const int N = 5005;

int T, n, vn, p[N], lg[N], dep[N], vis[N], f[N][13];
long long ans;
bool used[N], on[N];
vector<int> e[N], id[N];

void dfs(int u, int fa) {
	dep[u] = dep[fa] + 1;
	f[u][0] = fa;
	for (int j = 1; j <= 12; j++) {
		f[u][j] = f[f[u][j - 1]][j - 1];
	}
	for (int v : e[u]) {
		if (v == fa) {
			continue;
		}
		dfs(v, u);
	}
}

int LCA(int u, int v) {
	if (dep[u] < dep[v]) {
		swap(u, v);
	}
	while (dep[u] > dep[v]) {
		u = f[u][lg[dep[u] - dep[v]]];
	}
	if (u == v) {
		return u;
	}
	for (int j = 12; j >= 0; j--) {
		if (f[u][j] != f[v][j]) {
			u = f[u][j];
			v = f[v][j];
		}
	}
	return f[u][0];
}

int dis(int u, int v) {
	return dep[u] + dep[v] - 2 * dep[LCA(u, v)];
}

void col(int x);

void coln(int u) {
	for (int v = f[u][0]; v; v = f[v][0]) {
		if (!used[v]) {
			col(vis[v]);
		}
	}
}

void col(int x) {
	for (int u : id[x]) {
		used[u] = 1;
	}
	for (int u : id[x]) {
		coln(u);
	}
}

void find(int u, int fa) {
	on[u] = p[u] != u;
	for (int v : e[u]) {
		if (v == fa) {
			continue;
		}
		find(v, u);
		on[u] |= on[v];
	}
}

void getans(int u, int fa) {
	if (!used[u]) {
		if (u > 1 && on[u]) {
			ans += 2;
		}
		col(vis[u]);
	}
	for (int v : e[u]) {
		if (v == fa) {
			continue;
		}
		getans(v, u);
	}
}

void work() {
	cin >> n;
	for (int i = 1; i <= n; i++) {
		cin >> p[i];
	}
	for (int i = 1; i <= n; i++) {
		e[i].clear();
	}
	for (int i = 1; i < n; i++) {
		int u, v;
		cin >> u >> v;
		e[u].emplace_back(v);
		e[v].emplace_back(u);
	}
	dfs(1, 0);
	ans = 0;
	for (int i = 1; i <= n; i++) {
		ans += dis(i, p[i]);
	}
	for (int i = 1; i <= n; i++) {
		vis[i] = 0;
		used[i] = 0;
		on[i] = 0;
	}
	for (int i = 1; i <= n; i++) {
		if (vis[i]) {
			continue;
		}
		vn++;
		id[vn].clear();
		for (int u = i; !vis[u]; u = p[u]) {
			vis[u] = vn;
			id[vn].emplace_back(u);
		}
	}
	find(1, 0);
	getans(1, 0);
	cout << ans << '\n';
}

int main() {
	// freopen("classic.in", "r", stdin);
	// freopen("classic.out", "w", stdout);
	ios::sync_with_stdio(0);
	cin.tie(0);
	for (int i = 2; i < N; i++) {
		lg[i] = lg[i / 2] + 1;
	}
	// cin >> T;
	T = 1;
	while (T--) {
		work();
	}

	return 0;
}