#include <bits/stdc++.h>
#define FAST_IO ios_base::sync_with_stdio(0); cin.tie(nullptr); cout.tie(nullptr)
#define FOR(i, begin, end) for(int i = (begin); i < (end); i++)
#define TSTS int ttt; cin >> ttt; while(ttt--) solve()
#define all(x) (x).begin(), (x).end()
#define le(vec) vec[vec.size()-1]
#define sz(x) ((int)((x).size()))
#define pb push_back
#define s second
#define f first
using namespace std;
typedef long long ll;
typedef long double ld;
typedef vector<int> vi;
typedef map<int, int> mii;
typedef pair<int, int> pii;
typedef pair<long long, long long> pll;
typedef pair<long double, long double> pdd;
const int INF=1e9, MOD=1e9+7, mod=998244353;
const ll LINF=1e18;
void setIO()
{
FAST_IO;
}
void setIO(string s)
{
FAST_IO;
freopen((s+".in").c_str(), "r", stdin);
freopen((s+".out").c_str(), "w", stdout);
}
const int N=2e5+10, R=25010;
int n, r, q, t, rg[N], tin[N], tout[N], id;
ll pre[510][N], pref[N];
vi ad[N], gr[R], st[R];
set<int> big;
mii c;
void build(int u)
{
tout[u]=tin[u]=++t;
for(auto x : ad[u]){
build(x);
tout[u]=max(tout[u], tout[x]);
}
}
int main()
{
setIO();
cin >> n >> r >> q;
cin >> rg[0];
gr[rg[0]].pb(0);
FOR(i, 1, n)
{
int x; cin >> x;
x--; cin >> rg[i];
gr[rg[i]].pb(i);
ad[x].pb(i);
}
build(0);
int sq=sqrt(n);
FOR(i, 1, r+1)
{
if(sz(gr[i])>sq){
big.insert(i);
}
}
for(auto x : big) c[x]=++id;
for(auto x : big){
FOR(i, 0, n+1) pref[i]=0;
for(auto i : gr[x]){
pref[tin[i]]++;
pref[tout[i]+1]--;
}
FOR(i, 1, n+1) pref[i]+=pref[i-1];
FOR(i, 1, r+1)
{
for(auto j : gr[i]){
pre[c[x]][i]+=pref[tin[j]];
}
}
}
FOR(i, 1, r+1)
{
for(auto x : gr[i]){
st[i].pb(tin[x]);
}
sort(all(st[i]));
}
while(q--){
int r1, r2;
cin >> r1 >> r2;
if(!big.count(r1)){
ll ans=0;
for(auto i : gr[r1]){
int le=-1, ri=sz(st[r2])-1;
while(le<ri){
int m=(le+ri+1)/2;
if(st[r2][m]>tout[i]) ri=m-1;
else le=m;
}
int l0=0, r0=sz(st[r2]);
while(l0<r0){
int m0=(l0+r0)/2;
if(st[r2][m0]<tin[i]) l0=m0+1;
else r0=m0;
}
if(le!=-1&&l0!=sz(st[r2])){
ans+=le-l0+1;
}
}
cout << ans << endl;
}
else{
cout << pre[c[r1]][r2] << endl;
}
}
}
