#include <bits/stdc++.h>
#define NOSYNC ios::sync_with_stdio(false); cin.tie(0); cout.tie(0)
#define all(x) x.begin(), x.end()
#define endl '\n'
using namespace std;
using ll = long long;
using ull = unsigned long long;

const int N = 200005;

// -------------- Templates Above -------------------------

int n, m, q;
vector<int> g[N];
int dfn[N], siz[N], b[N], dfncnt;
int tp[N];

void dfs(int x, int fa) {
	siz[x] = 1;
	dfn[x] = ++ dfncnt;
	for(int y : g[x]) {
		if(y == fa) continue;
		dfs(y, x);
		siz[x] += siz[y];
	}
}

int in(int x, int y) { // x 是否在 y 的子树内
	if(dfn[y] <= dfn[x] && dfn[x] <= dfn[y] + siz[y] - 1) return 1;
	return 0;
}

int get(int x) {
	// x ~ x + 1 的答案
	// a, b, c 为 x, x+1, x+2
	int y = x + 1, z = x + 2;
	int A = b[x], B = b[y], C = b[z];
	if(tp[x] == 0 && tp[y] == 0) {
		return 0;
	}
	else if(tp[x] == 0 && tp[y] == 1) {
		if(!in(C, B)) return 0;
		if(in(C, A) || in(A, C)) return 1;
		return 0;
	}
	else if(tp[x] == 1 && tp[y] == 0) {
		return 1;
	}
	else if(tp[x] == 1 && tp[y] == 1) {
		if(in(C, B)) return 0;
		return 1;
	}
}


signed main() {
	NOSYNC;
	cin >> n >> m >> q;
	for(int i = 1; i < n; i ++) {
		int u, v; cin >> u >> v;
		g[u].push_back(v);
		g[v].push_back(u);		
	}
	for(int i = 1; i <= m; i ++) {
		cin >> b[i];
	}
	dfs(1, 1);
	for(int i = 1; i < m; i ++) {
		int j = i + 1; // a = bi, b = bj
		if(in(b[i], b[j])) {
			tp[i] = 0;
		}
		else tp[i] = 1;
	}
	int ans = 2;
	for(int i = 1; i < m - 1; i ++) {
		ans += get(i);
	}
	// for(int i = 1; i < m; i ++) {
		// cout << tp[i] << " ";
	// }cout << endl;
	// cout << "ans: " << ans << endl;
	
	for(int i = 1; i <= q; i ++) {
		int p, w; cin >> p >> w;
		// 改变 tp[p], tp[p-1]
		// 重新统计答案:p-2, p-1, p
		if(p == m) {
			// 改变 p-1
			// 重新统计答案：p-2
			ans -= get(p-2);
			b[p] = w;
			if(in(b[p-1], b[p])) tp[p-1] = 0;
			else tp[p-1] = 1;
			ans += get(p-2);
		}
		else if(p == 1) {
			// 改变 p
			// 重新统计答案：p
			ans -= get(p);
			b[p] = w;
			if(in(b[p], b[p+1])) tp[p] = 0;
			else tp[p] = 1;
			ans += get(p);
		}
		else {
			// 判一下 p-2 是否要统计
			// 判一下 p 是否要统计
			if(p-2 >= 1) {
				ans -= get(p-2);
			}
			if(p <= m-2) {
				ans -= get(p);
			}
			ans -= get(p-1);
			
			b[p] = w;
			if(in(b[p-1], b[p])) tp[p-1] = 0;
			else tp[p-1] = 1;
			if(in(b[p], b[p+1])) tp[p] = 0;
			else tp[p] = 1;
			
			if(p-2 >= 1) {
				ans += get(p-2);
			}
			if(p <= m-2) {
				ans += get(p);
			}
			ans += get(p-1);
		}
		cout << ans << endl;
	}
	
	return 0;
}