#include<iostream>
#include<cstdio>
#include<vector>
#include<set>
#include<cassert>
#define N 1000000
#define M 21000000
using namespace std;
int read()
{
    char c=0;
    int sum=0;
    while (c<'0'||c>'9') c=getchar();
    while ('0'<=c&&c<='9') sum=sum*10+c-'0',c=getchar();
    return sum;
}
struct reads
{
    int num,data;
    bool operator < (const reads &t)const
    {
	return data!=t.data?data>t.data:num<t.num;
    }
};
int type,n,m,cater,rt[N+1],lst[N+1],dfn[N+1],sz[N+1],a[N+1],fa[N+1],cnt[N+1],ls[N+1],leng[N+1],lengs[N+1],lengs2[N+1],dp[N+1],DP[N+1],DPS[N+1];
bool used[N+1];
vector<int>E[N+1];
set<reads>s[N+1];
struct bit
{
    int c[N+1];
    int lowbit(int x)
    {
	return x&(-x);
    }
    void add(int x,int d)
    {
	for (;x<=n;x+=lowbit(x)) c[x]^=d;
	return;
    }
    int query(int x)
    {
	int res=0;
	for (;x>=1;x-=lowbit(x)) res^=c[x];
	return res;
    }
};
bit T;
struct trie
{
    int length,top,tmp[22],rt[N+1],sn[M+1][2],cnt[M+1],dque[M+1];
    int new_node()
    {
	if (top) return dque[top--];
	else return ++length;
    }
    void add(int x,int d1,int d2,int d)
    {
	int ps=21;
	tmp[21]=x;
	for (int i=20;i>=0;--i)
	{
	    if (!sn[x][((d1^d2)>>i)&1]) sn[x][((d1^d2)>>i)&1]=new_node();
	    if (!(d2&(1<<i))) cnt[sn[x][((d1^d2)>>i)&1]]+=d;
	    x=sn[x][((d1^d2)>>i)&1],tmp[i]=x;
	    if (cnt[x]||(i&&sn[x][(((d1^d2)>>(i-1))&1)^1])) ps=i;
	}
	for (int i=ps-1;i>=0;--i) sn[tmp[i]][0]=sn[tmp[i]][1]=0,dque[++top]=tmp[i];
	if (ps) sn[tmp[ps]][tmp[ps-1]==sn[tmp[ps]][1]]=0;
	return;
    }
    int query(int x,int d)
    {
	int res=0;
	for (int i=20;i>=0;--i)
	{
	    res+=cnt[sn[x][((d>>i)&1)^1]],x=sn[x][((d>>i)&1)];
	    if (!x) break;
	}
	return res;
    }
};
trie T2;
void add(int x,int y)
{
    E[x].push_back(y),E[y].push_back(x);
    return;
}
void adder(int x,int y,int d)
{
    dp[x]^=dp[y];
    if (a[x]&1) dp[x]^=leng[x];
    if (d==1) s[x].insert((reads){y,leng[y]});
    else s[x].erase((reads){y,leng[y]});
    leng[x]=s[x].empty()?0:(*s[x].begin()).data+1;
    if (a[x]&1) dp[x]^=leng[x];
    return;
}
void dfs(int x)
{
    dfn[x]=++cater,used[x]=sz[x]=1;
    for (int i=0;i<E[x].size();++i)
	if (!used[E[x][i]])
	    fa[E[x][i]]=x,dfs(E[x][i]),adder(x,E[x][i],1),sz[x]+=sz[E[x][i]];
    ls[x]=s[x].empty()?0:(*s[x].begin()).num;
    return;
}
void dfs2(int x)
{
    DP[x]=dp[x],lengs[x]=leng[x],lst[x]=s[x].empty()?0:(*s[x].begin()).num;
    if (s[x].size()>=2)
    {
	auto it=s[x].begin();
	it++,lengs2[x]=(*it).data+1;
    }
    else lengs2[x]=0;
    for (int i=0;i<E[x].size();++i)
	if (fa[E[x][i]]==x)
	    adder(x,E[x][i],-1),adder(E[x][i],x,1),dfs2(E[x][i]),adder(E[x][i],x,-1),adder(x,E[x][i],1);
    return;
}
void rebuild(int x,int y)
{
    T2.add(rt[x],DPS[y],lengs[y],-1),DPS[y]=DP[y]^(T.query(dfn[x])^T.query(dfn[y])),T2.add(rt[x],DPS[y],lengs[y],1);
    return;
}
void solve(int x)
{
    T.add(1,leng[x]),T.add(dfn[x],leng[x]),T.add(dfn[x]+sz[x],leng[x]);
    T.add(dfn[x],lengs[x]),T.add(dfn[x]+sz[x],lengs[x]);
    if (ls[x]&&lst[x]==ls[x]) T.add(dfn[ls[x]],lengs[x]^lengs2[x]),T.add(dfn[ls[x]]+sz[ls[x]],lengs[x]^lengs2[x]);
    if (fa[x]) rebuild(fa[x],x);
    if (ls[x]) rebuild(x,ls[x]);
    a[x]++;
    return;
}
int query(int x)
{
    int res=T2.query(rt[x],T.query(dfn[x]));
    res+=((DP[x]^T.query(dfn[x]))>lengs[x]);
    if (fa[x]) res+=((DP[fa[x]]^T.query(dfn[fa[x]]))>lengs[fa[x]]);
    return res;
}
int main()
{
    int x,y;
    type=read(),T2.length=n=read(),m=read();
    for (int i=1;i<=n-1;++i) x=read(),y=read(),add(x,y);
    for (int i=1;i<=n;++i) a[i]=read(),rt[i]=i;
    dfs(1),dfs2(1);
    for (int i=1;i<=n;++i) DPS[i]=DP[i];
    for (int i=1;i<=n;++i)
	for (int j=0;j<E[i].size();++j)
	    if (fa[E[i][j]]==i)
		T2.add(rt[i],DP[E[i][j]],lengs[E[i][j]],1);
    while (m--) x=read(),y=read(),solve(x),printf("%d\n",query(y));
    return 0;
}