#include<bits/stdc++.h>
#define ll long long
using namespace std;
vector<ll> par,B;
vector<vector<ll>> A;
vector<vector<pair<ll,ll>>> C;
vector<pair<ll,ll>> r;
ll cnt=0;
void dfs(ll u,ll p){
r[u].first=cnt++;
for(auto v:A[u]){
if(v!=p) dfs(v,u);
}
r[u].second=cnt++;
C[B[u]].push_back({r[u].first,r[u].second});
}
int main(){
ll n,q,R,i,j,k,x,y,b,r1,r2,ans;
cin>>n>>R>>q;
par.resize(n+1);
A.resize(n+1);
B.resize(n+1);
C.resize(R+1);
r.resize(n+1);
cin>>x;
B[1]=x;
vector<ll> deg(n+1,0);
for(i=2 ; i<=n ; i++){
cin>>par[i]>>x;
A[i].push_back(par[i]);
A[par[i]].push_back(i);
B[i]=x;
deg[i]++;
deg[par[i]]++;
}
queue<ll> qu;
for(i=1 ; i<=n ; i++){
if(deg[i]==1) qu.push(i);
}
dfs(1,1);
vector<ll> sup(n+1,0),a(n+1,1);
while(!qu.empty()){
ll u=qu.front();
qu.pop();
for(auto v:A[u]){
if(v!=sup[u]){
deg[v]--;
if(deg[v]<=1) qu.push(v);
sup[v]=u;
a[v]+=a[u];
}
}
}
for(i=1 ; i<=R ; i++){
sort(C[i].rbegin(),C[i].rend());
}
for(i=0 ; i<q ; i++){
cin>>r1>>r2;
ans=0;
if(R==1){
cout<<a[1]-1<<"\n";
continue;
}
for(auto v:C[r1]){
ll ng1=C[r2].size();
ll ok1=-1;
while(ng1-ok1>1){
ll mid=(ng1+ok1)/2;
if(C[r2][mid].first>v.second) ok1=mid;
else ng1=mid;
}
ll ok2=ng1-1;
ll ng2=C[r2].size();
while(ng2-ok2>1){
ll mid=(ng2+ok2)/2;
if(C[r2][mid].first<v.first) ng2=mid;
else ok2=mid;
}
ans+=ok2-ng1+1;
}
cout<<ans<<"\n";
}
return 0;
}
