#include <bits/stdc++.h>
using namespace std;
constexpr int MAX_N = 500'000 + 50;
int N, K;
int S[MAX_N], Cnt[MAX_N], Dp[MAX_N];
bool IsStar[MAX_N];
map<int, int> Mp[MAX_N];
vector<int> Adj[MAX_N];
void Dfs(int v=1, int p=0) {
if (Cnt[S[v]] > 1) Mp[v][S[v]]++;
for (auto &nxt: Adj[v]) {
if (nxt == p) continue;
Dfs(nxt, v);
Dp[v] += Dp[nxt];
if (Mp[nxt].size() > Mp[v].size()) swap(Mp[nxt], Mp[v]);
for (auto &[s, c]: Mp[nxt]) {
Mp[v][s] += c;
if (Mp[v][s] == Cnt[s]) Mp[v].erase(s);
}
}
if (v != 1 && Mp[v].empty()) {
IsStar[v] = true;
if (Dp[v] == 0) Dp[v] = 1;
}
}
vector<int> I;
void GetI(int v=1, int p=0) {
if (IsStar[v]) {
I.push_back(Dp[v]);
return;
}
for (auto &nxt: Adj[v]) {
if (nxt == p) continue;
GetI(nxt, v);
}
}
int main() {
cin.tie(nullptr)->sync_with_stdio(false);
cin >> N >> K;
for (int i = 0; i < N - 1; i++) {
int u, v; cin >> u >> v;
Adj[u].push_back(v);
Adj[v].push_back(u);
}
for (int i = 1; i <= N; i++) {
cin >> S[i];
Cnt[S[i]]++;
}
Dfs();
GetI();
vector<vector<int>> vp(2);
int s = 0;
for (auto &i: I) {
vp[i % 2].push_back(i);
s += i;
}
int ans = s / 2;
if ((vp[1].size() % 2) == 1) ans++;
cout << ans << '\n';
}
