#include<bits/stdc++.h>
using namespace std;
constexpr int N=200005;
int n,m,q;
int b[N];
vector<int>G[N];
int dfn[N],siz[N],Index;
void dfs(int u,int father)
{
    dfn[u]=++Index;
    siz[u]=1;
    for(int v:G[u])
    {
        if(v==father) continue;
        dfs(v,u);
        siz[u]+=siz[v];
    }
    return;
}
bool inside(int u,int v)
{
    return dfn[u]<=dfn[v]&&dfn[v]<=dfn[u]+siz[u]-1;
}
int relation(int u,int v)
{
    if(inside(u,v)) return 0;
    else if(inside(v,u)) return 1;
    else return 0;
}
bool check(int a,int b,int c)
{
    if(a==0||c==0) return true;
    int ll=inside(b,a),rr=inside(b,c);
    return ll==rr;
}
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr),cout.tie(nullptr);
    cin>>n>>m>>q;
    for(int i=1;i<n;i++)
    {
        int u,v;
        cin>>u>>v;
        G[u].emplace_back(v);
        G[v].emplace_back(u);
    }
    for(int i=1;i<=m;i++)
        cin>>b[i];
    dfs(1,0);
    int ans=1;
    for(int i=1;i<m;i++)
        if(check(b[i-1],b[i],b[i+1])) ans++;
    while(q--)
    {
        int i,w;
        cin>>i>>w;
        if(i+2<=m)
        {
            if(check(b[i],b[i+1],b[i+2])) ans--;
        }
        if(i+1<=m)
        {
            if(check(b[i-1],b[i],b[i+1])) ans--;
        }
        if(i-1>=1)
        {
            if(check(b[i-2],b[i-1],b[i])) ans--;
        }
        b[i]=w;
        if(i+2<=m)
        {
            if(check(b[i],b[i+1],b[i+2])) ans++;
        }
        if(i+1<=m)
        {
            if(check(b[i-1],b[i],b[i+1])) ans++;
        }
        if(i-1>=1)
        {
            if(check(b[i-2],b[i-1],b[i])) ans++;
        }
        cout<<ans<<"\n"; 
    }
    return 0;
}
 
 
 /*
 5 5 0
2 1
3 2
1 4
5 1
3 5 3 2 3
*/