#include<bits/stdc++.h>
#define ll long long
#define pb push_back
using namespace std;
const int N=2e5+5;
int n,m,qsn,ne[N],b[N],ans,la[N];
int dep[N],fa[N][22],lg;
vector<int> G[N];
void dfs(int x,int y){
    dep[x]=dep[y]+1,fa[x][0]=y;
    for(int i=1;dep[x]-(1<<i)>=1;++i)
    fa[x][i]=fa[fa[x][i-1]][i-1];
    for(auto&i:G[x])
    if(i!=y)
    dfs(i,x);
}
int lca(int x,int y){
    if(dep[x]<dep[y])swap(x,y);
    for(int i=0;dep[x]^dep[y];++i)if((dep[x]-dep[y])&(1<<i))x=fa[x][i];
    if(x==y)return x;
    for(int i=lg;i>=0;--i)if(fa[x][i]!=fa[y][i])x=fa[x][i],y=fa[y][i];
    return fa[x][0];
}
int hs(int x,int y,int z){
    int xz=lca(x,z);
    if(lca(y,xz)!=xz)return 1;
    if(lca(x,y)==y)return 0;
    if(lca(z,y)==y)return 0;
    return 1;
}
void work(int a0,int a1,int b0,int b1){
    if((a0==a1)==(b0==b1))return;
    if(a0==a1)--ans;
    else ++ans;
}
int main()
{
    //ios::sync_with_stdio(false);
    //cin.tie(0);cout.tie(0);
    scanf("%d%d%d",&n,&m,&qsn);
    lg=log(n)/log(2)+1;
    for(int i=1;i<n;++i){
        int x,y;scanf("%d%d",&x,&y);
        G[x].pb(y),G[y].pb(x);
    }
    dfs(1,0);
    for(int i=1;i<=m;++i)scanf("%d",&b[i]);
    ans=2;
    for(int i=2;i<n;++i)ans+=hs(b[i-1],b[i],b[i+1]);
    while(qsn--)
{
    int p,w;scanf("%d%d",&p,&w);
    if(m==1){printf("1\n");continue;}
    if(p>2)
    ans+=hs(b[p-2],b[p-1],w)-hs(b[p-2],b[p-1],b[p]);
    if(p>1&&p<n)
    ans+=hs(b[p-1],w,b[p+1])-hs(b[p-1],b[p],b[p+1]);
    if(p<n-1)
    ans+=hs(w,b[p+1],b[p+2])-hs(b[p],b[p+1],b[p+2]);
    b[p]=w;
    printf("%d\n",ans);
}
    return 0;
}
/*
modify i
change ne[i],ne[i-1]
*/