#include<bits/stdc++.h>
#define fi first
#define se second
#define int long long
using namespace std;
using ll = long long;
using ii = pair<int, int>;
using aa = array<int,4>;
const int N = 2e5+5;
const ll INF = 1e18;
const int MOD = 1e9+7;
const int base = 31;
int n, u, v, ans = 0;
int gen[N], dp[N];
char c;
vector <int> adj[N];
void dfs(int u,int p){
for (int it : adj[u]){
if (it == p) continue;
dfs(it,u);
dp[u] += dp[it];
ans = max(ans,dp[it] + gen[u]);
}
dp[u] = max(dp[u] - gen[u],gen[u]);
ans = max(ans,dp[u]);
}
signed main(){
ios_base::sync_with_stdio(false);
cin.tie(NULL);cout.tie(NULL);
cin >> n;
for (int i = 1; i < n; i++){
cin >> u >> v;
adj[u].push_back(v);
adj[v].push_back(u);
}
for (int i = 1; i <= n; i++){
cin >> c;
gen[i] = (c - '0');
}
dfs(1,0);
cout << ans;
return 0;
}
