#include<bits/stdc++.h>
using namespace std;
typedef long long LL;
const int N=2e5+5,M=2*N;

int n,m,q,b[N],deep[N],f[N],h1[N],son[N];
int lian[N],top_lian[N];
int a[N],c[N];
int h[N],e[N],ne[N],idx;

void add(int u,int v){
    e[idx]=v,ne[idx]=h[u],h[u]=idx++;
}

bool vis[N];
void dfs1(int u){
    vis[u]=true;
    for(int i=h[u];~i;i=ne[i]){
        int v=e[i];
        if(vis[v]) continue;
        deep[v]=deep[u]+1;
        f[v]=u;
        dfs1(v);
        if(h1[v]+1>h1[u]){
            h1[u]=h1[v]+1;
            son[u]=v;
        }
    }
}

void dfs2(int u){
    for(int i=h[u];~i;i=ne[i]){
        int v=e[i];
        if(v==f[u]) continue;
        if(v==son[u]){
            lian[v]=lian[u];
        }else{
            lian[v]=++idx;
            top_lian[idx]=v;
        }
        dfs2(v);
    }
}

int main(){
    cin>>n>>m>>q;
    memset(h,-1,sizeof h);
    a[1]=c[n]=-1;
    int u,v,ans=2;
    for(int i=1;i<n;i++){
        cin>>u>>v;
        add(u,v),add(v,u);
    }
    idx=0;
    deep[1]=1;
    dfs1(1);
    lian[1]=++idx;
    top_lian[idx]=1;
    dfs2(1);
    cin>>b[1];
    for(int i=2;i<=m;i++){
        cin>>b[i];
        int x=b[i],y=b[i-1],last;
        bool flag=false;
        if(deep[x]>deep[y]) swap(x,y),flag=true;
        while(lian[x]!=lian[y]){
            if(deep[top_lian[lian[x]]]>deep[top_lian[lian[y]]]){
                break;
            }
            last=y;
            y=f[top_lian[lian[y]]];
        }
        if(lian[x]!=lian[y]) continue;
        if(flag){
            if(deep[x]<deep[y]) c[i-1]=lian[x];
            else if(deep[x]==deep[y]) c[i-1]=lian[last];
        }else{
            if(deep[x]<deep[y]) a[i]=lian[x];
            else if(deep[x]==deep[y]) a[i]=lian[last];
        }
    }

    for(int i=2;i<=m;i++){
        if(a[i]==c[i]){
            ans++;
            //cout<<b[i]<<":"<<a[i]<<" "<<c[i]<<endl;
        }
    }
    //cout<<ans<<endl;
    int p;
    while(q--){
        cin>>p>>u;
        b[p]=u;
        if(a[p]==c[p]) ans--;
        if(p!=1){
            if(a[p-1]==c[p-1]) ans--;
            int x=b[p],y=b[p-1],last;
            bool flag=false;
            if(deep[x]>deep[y]) swap(x,y),flag=true;
            while(lian[x]!=lian[y]){
                if(deep[top_lian[lian[x]]]>deep[top_lian[lian[y]]]){
                    break;
                }
                last=y;
                y=f[top_lian[lian[y]]];
            }
            if(lian[x]!=lian[y]) a[p]=0,c[p-1]=0;
            else if(flag){
                a[p]=0;
                if(deep[x]<deep[y]) c[p-1]=lian[x];
                else if(deep[x]==deep[y]) c[p-1]=lian[last];
            }else{
                if(deep[x]<deep[y]) a[p]=lian[x];
                else if(deep[x]==deep[y]) a[p]=lian[last];
                c[p-1]=0;
            }
            if(a[p-1]==c[p-1]) ans++;
        }
        if(p!=n){
            if(a[p+1]==c[p+1]) ans--;
            int x=b[p+1],y=b[p],last;
            bool flag=false;
            if(deep[x]>deep[y]) swap(x,y),flag=true;
            while(lian[x]!=lian[y]){
                if(deep[top_lian[lian[x]]]>deep[top_lian[lian[y]]]){
                    break;
                }
                last=y;
                y=f[top_lian[lian[y]]];
            }
            if(lian[x]!=lian[y]) a[p+1]=0,c[p]=0;
            else if(flag){
                if(deep[x]<deep[y]) c[p]=lian[x];
                else if(deep[x]==deep[y]) c[p]=lian[last];
                a[p+1]=0;
            }else{
                if(deep[x]<deep[y]) a[p+1]=lian[x];
                else if(deep[x]==deep[y]) a[p+1]=lian[last];
                c[p]=0;
            }
            if(a[p+1]==c[p+1]) ans++;
        }
        if(a[p]==c[p]) ans++;
        cout<<ans<<endl;
        /*
        for(int i=1;i<=m;i++){
            cout<<b[i]<<":"<<a[i]<<" "<<c[i]<<endl;
        }
        */
    }
    return 0;
}
/*
5 5 3
2 1
3 2
1 4
5 1
1 5 4 2 3
1 3
5 3
3 3
*/