#include <bits/stdc++.h>
using namespace std;
const int nx=2e5+5;
int n, x, q, p, in[nx], out[nx], t, a, b;
vector<int> d[nx], r[nx];
struct fenwick
{
int d[nx];
void update(int i, int vl) {while (i<nx) d[i]+=vl, i+=(i&-i);}
int query(int i)
{
int res=0;
while (i>0) res+=d[i], i-=(i&-i);
return res;
}
} f;
void dfs(int u)
{
in[u]=++t;
for (auto v:d[u]) dfs(v);
out[u]=t;
}
int main()
{
cin>>n>>x>>q;
cin>>x;
r[x].push_back(1);
for (int i=2; i<=n; i++) cin>>p>>x, d[p].push_back(i), r[x].push_back(i);
dfs(1);
while (q--)
{
cin>>a>>b;
for (auto x:r[b]) f.update(in[x], 1);
int res=0;
for (auto x:r[a]) res+=f.query(out[x])-f.query(in[x]-1);
for (auto x:r[b]) f.update(in[x], -1);
cout<<res<<'\n';
fflush(stdout);
}
}
