//#pragma GCC optimize("O3,unroll-loops,Ofast")
//#pragma GCC target("avx2,bmi,bmi2,popcnt,lzcnt")
#include <bits/stdc++.h>
// #include <ext/pb_ds/assoc_container.hpp>
// #include <ext/pb_ds/tree_policy.hpp>
using namespace std;
// using namespace __gnu_pbds;
#define MAX 200005
#define pb push_back
// #define mp make_pair
#define int long long
// #define double long double
#define f first
#define s second
#define vi vector<int>
#define pii pair<int,int>
#define si set<int>
#define vpii vector<pair<int,int>>
const int mod = 1e9+7;
const int INF = 1e18;
// myMap.begin()->first : key
// myMap.begin()->second : value
int epow(int a,int b){int ans=1;while(b){if(b&1) ans*=a;a*=a;b>>=1;ans%=mod;a%=mod;}return ans%mod;}
int gcd(int a,int b) {if(a<b)swap(a,b);while(b){int tmp=b;b=a%b;a=tmp;}return a;}
int mul(int a,int b){return ((a%mod)*(b%mod))%mod;}
int sum(int a,int b){return ((a%mod)+(b%mod))%mod;}
//typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update>ordered_set;
// typedef
// tree<int,null_type,less_equal<int>,rb_tree_tag,tree_order_statistics_node_update>ordered_multiset;
vi dsu(MAX),sz(MAX);
int find(int a){
if(dsu[a]==a) return a;
return dsu[a]=find(dsu[a]);
}
void unite(int a,int b){
a=find(a); b=find(b);
if(a==b) return;
if(sz[a]<sz[b]) swap(a,b);
sz[a]+=sz[b]; dsu[b]=a;
}
vi segt(MAX*4),lazy(MAX*4);
void push(int v,int tl,int tr){
if(!lazy[v]) return;
segt[v]+=lazy[v];
if(tl!=tr){
lazy[v*2]+=lazy[v]; lazy[v*2+1]+=lazy[v];
}
lazy[v]=0;
}
void update(int v,int tl,int tr,int l,int r,int val){
push(v,tl,tr);
if(tl>r || tr<l || l>r) return;
if(tl>=l && tr<=r){
lazy[v]+=val; push(v,tl,tr); return;
}
int mid=(tl+tr)>>1;
update(v*2,tl,mid,l,r,val); update(v*2+1,mid+1,tr,l,r,val);
segt[v]=segt[v*2]+segt[v*2+1];
}
int query(int v,int tl,int tr,int l,int r){
push(v,tl,tr);
if(tl>r || tr<l || l>r) return 0;
if(tl>=l && tr<=r) return segt[v];
int mid=(tl+tr)>>1;
return query(v*2,tl,mid,l,r)+query(v*2+1,mid+1,tr,l,r);
}
vi euler[MAX];
int tin[MAX],tout[MAX],timer=1,p[MAX][22],dep[MAX],type[MAX];
vi adj[MAX];
void dfs(int node,int par){
tin[node]=timer++; dep[node]=dep[par]+1; p[node][0]=par; for(int i=1;i<=20;i++) p[node][i]=p[p[node][i-1]][i-1];
euler[type[node]].pb(tin[node]);
for(auto u : adj[node]){
if(u!=par) dfs(u,node);
}
tout[node]=timer-1;
}
int find_lca(int a,int b){
if(dep[a]<dep[b]) swap(a,b);
int fark=dep[a]-dep[b];
for(int i=20;i>=0;i--){
if(fark&(1<<i)) a=p[a][i];
}
if(a==b) return a;
for(int i=20;i>=0;i--){
if(p[a][i]!=p[b][i]) a=p[a][i],b=p[b][i];
}
return p[a][0];
}
int up(int node,int x){
for(int i=20;i>=0;i--){
if(x&(1<<i)) node=p[node][i];
}
return node;
}
set<array<int,3>> calc;
set<int> st[MAX];
void dfs2(int node,int par){
for(auto u : adj[node]){
if(u==par) continue;
dfs2(u,node);
if(st[u].size()>st[node].size()) swap(st[node],st[u]);
for(auto x : st[u]) st[node].insert(x);
}
for(auto u : st[node]){
int l=lower_bound(euler[u].begin(),euler[u].end(),tin[node]+1)-euler[u].begin();
int r=upper_bound(euler[u].begin(),euler[u].end(),tout[node])-euler[u].begin();
array<int,3> a={type[node],u,u};
auto itr = lower_bound(calc.begin(),calc.end(),a);
if(itr==calc.end() || (*itr)[0]!=type[node] || (*itr)[1]!=u) calc.insert({type[node],u,r-l});
else{
int newval=(*itr)[2]+r-l;
calc.erase(itr); calc.insert({{type[node],u,newval}});
}
}
st[node].insert(type[node]);
}
void solve(){
int n,r,q; cin>>n>>r>>q;
cin>>type[1];
for(int i=2;i<=n;i++){
int p,tur; cin>>p>>tur; adj[p].pb(i); adj[i].pb(p); type[i]=tur;
}
dfs(1,0);
dfs2(1,0);
// for(auto u : calc) cout<<u[0]<<" "<<u[1]<<" "<<u[2]<<endl;
while(q--){
int a,b; cin>>a>>b; array<int,3> c={a,b,-1};
auto itr = lower_bound(calc.begin(),calc.end(),c);
if(itr==calc.end() || (*itr)[0]!=a || (*itr)[1]!=b) cout<<"0"<<endl;
else cout<<(*itr)[2]<<endl;
}
}
int32_t main(/*int32_t argc, char* argv[]*/){
std::ios_base::sync_with_stdio(0); std::cin.tie(0);
// freopen("promote.in", "r", stdin);
// freopen("promote.out", "w", stdout);
int t=1;
// cin >> t;
while (t--) solve();
return 0;
}
