#include<bits/stdc++.h>
#define FOR(i,a,b) for(int i=a;i<=b;++i)
#define ROF(i,a,b) for(int i=a;i>=b;--i)
#define pbk push_back
typedef long long ll;
using namespace std;
const int N=2e5+7;
int n,m,q,fa[N][20],ok[N],su,sq[N],d[N];
vector<int>a[N];
void dfs(int x,int f){
    fa[x][0]=f,d[x]=d[f]+1;
    FOR(i,1,19)fa[x][i]=fa[fa[x][i-1]][i-1];
    for(int to:a[x])if(to!=f)dfs(to,x);
}
int LCA(int u,int v){
    if(d[u]<d[v])swap(u,v);
    ROF(i,19,0){
        int f=fa[u][i];
        if(d[f]>=d[v])u=f;
    }
    if(u==v)return u;
    ROF(i,19,0){
        int f=fa[u][i],fv=fa[v][i];
        if(f!=fv)u=f,v=fv;
    }
    return fa[u][0];
}
void chk(int x){
    su-=ok[x];
    int u=sq[x-1],v=sq[x+1],c=sq[x],w=LCA(u,v);
    set<int>rt={c,w},nw={LCA(u,c),LCA(v,c)};
    ok[x]=(rt==nw);
//    cout<<u<<' '<<v<<' '<<c<<' '<<ok[x]<<endl;
    su+=ok[x];
}
int main(){
    scanf("%d%d%d",&n,&m,&q);
    FOR(i,2,n){
        int u,v;
        scanf("%d%d",&u,&v);
        a[u].pbk(v),a[v].pbk(u);
    }
    dfs(1,0);
    FOR(i,1,m)scanf("%d",sq+i);
    FOR(i,2,m-1)chk(i);
    while(q--){
        int x,v;
        scanf("%d%d",&x,&v);
        sq[x]=v;
        FOR(i,max(x-1,2),min(m-1,x+1)){
            chk(i);
        }
        printf("%d\n",m-su);
    }
    return 0;
}