#include <fstream>
#include <vector>
#include <algorithm>
#include <set>
#define pii pair<int, int>
using namespace std;
int n, val[200100], nrord, st[200100], dr[200100], best[200100], St[200100], Stbest[200100], vf;
vector <int> G[200100], G2[200100];
bool viz[200100];
set <pii> S;

inline void Citire()
{
	int i, x, y;
	ifstream fin("guvern.in");
	fin >> n;
	for(i = 1; i < n; ++i)
	{
		fin >> x >> y;
		G[x].push_back(y);
		G[y].push_back(x);
	}
	for(i = 1; i <= n; ++i)
		fin >> val[i];
	// pun o radacina fictiva cu valoare mare
	val[0] = 2000000000;
	G[0].push_back(1);
	fin.close();
}

inline bool Urmas(int a, int b) // daca a este urmas al lui b
{
	if(st[b] <= st[a] && dr[a] <= dr[b])
		return true;
	return false;
}

inline void DFS(int x)
{
	vector <int>::iterator it;
	S.insert(make_pair(val[x], x)); // introduc acum si nodul asta in set
	viz[x] = true;
	st[x] = ++nrord; // liniarizare arbore
	for(it = G[x].begin(); it != G[x].end(); ++it)
		if(!viz[*it])
			DFS(*it);
	dr[x] = ++nrord; // liniarizare arbore
	S.erase(make_pair(val[x], x)); // il scot din set ca ma intorc inapoi sus
	
	if(x != 0)
	{
		// caut sus pe lantul spre radacina nodul cu val minim >= val[x]
		set <pii>::iterator back = S.lower_bound(make_pair(val[x], x));
		G2[(*back).second].push_back(x);
	}
	
	int bestaux;
	vf = 0;
	for(it = G2[x].begin(); it != G2[x].end(); ++it)
	{
		++vf;
		St[vf] = *it;
		Stbest[vf] = best[*it];
		bestaux = 0;
		while(vf >= 2 && Urmas(St[vf - 1], St[vf]))
		{
			bestaux += Stbest[vf - 1];
			St[vf - 1] = St[vf];
			Stbest[vf - 1] = Stbest[vf];
			vf--;
		}
		Stbest[vf] = max(Stbest[vf], bestaux);
	}
	best[x] = 1;
	while(vf)
	{
		best[x] += Stbest[vf];
		vf--;
	}
}

inline void Afisare()
{
	ofstream fout("guvern.out");
	fout << (best[0] - 1) << "\n";
	fout.close();
}

int main()
{
	Citire();
	DFS(0);
	Afisare();
	return 0;
}