#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
#define rep(i, l, r) for (ll i = (l); i < (r); ++i)
#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()
using ll = long long;
using ull = unsigned long long;
using ld = long double;
using pl = pair<ll,ll>;
using vi = vector<int>;
using vl = vector<ll>;
using vvl = vector<vector<ll>>;
using vvvl = vector<vector<vector<ll>>>;
template<class T> using pq_ = priority_queue<T, vector<T>, greater<T>>;
#define sz(x) (int)(x).size()
typedef pair<int, int> pii;
using mint=modint998244353;
// g++ a.cpp -std=c++23 -I.
// g++ -std=c++23 -I. a.cpp -o main
// g++ -std=c++23 -I. anaive.cpp -o naive
// g++ -std=c++23 -I. agene.cpp -o gene
#include <boost/multiprecision/cpp_dec_float.hpp>
#include <boost/multiprecision/cpp_int.hpp>
namespace mp = boost::multiprecision;
using Bint = mp::cpp_int;
using Real = mp::number<mp::cpp_dec_float<1024>>;



int main(){
    ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    ll n;
    cin>>n;
    vl a(n-1);
    vl b(n-1);
    rep(i,0,n-1){
        cin>>a[i]>>b[i];
        a[i]--;
        b[i]--;
    }
    vl z(n);
    rep(i,0,n){
        cin>>z[i];
    }
    vvl g(n);
    ll ans=0;
    vl c(n);
    rep(i,0,n-1){
        if(z[a[i]]==z[b[i]])ans++;
        else if(z[a[i]]==1)c[b[i]]++;
        else if(z[b[i]]==1)c[a[i]]++;
        else {
            g[a[i]].push_back(b[i]);
            g[b[i]].push_back(a[i]);
        }
    }
    vector<bool> e(n,false);
    auto dfs = [&](auto self,ll now) -> array<ll,3> {
        vector<array<ll,2>> u;
        e[now]=true;
        vector<array<ll,3>> r;
        rep(i,0,g[now].size()){
            if(e[g[now][i]]==false){
                e[g[now][i]]=true;
                r.push_back(self(self,g[now][i]));
            }
        }
        array<ll,3> zans={0,0,0};
        ll e=-10000000000;
        rep(i,0,r.size()){
            zans[0]+=max(r[i][0],r[i][1]);
            zans[1]+=max(r[i][0],r[i][1]+1);
            e=max(e,r[i][2]+1-max(r[i][0],r[i][1]+1));
            zans[2]+=max(r[i][0],r[i][1]+1);
        }
        zans[1]+=e;
        zans[1]+=c[now];
        zans[2]+=c[now];
        return zans;
    };
    rep(i,0,n){
        if(z[i]!=1&&(!(c[i]))){
            auto u=dfs(dfs,i);
            ans+=max(u[0],u[1]);
        }
    }
    cout<<ans<<endl;
}