#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 2e5 + 3;
const int B = 1;
ll k;
int n, m, q, tick;
int a[N], p[N], tin[N], tout[N], pos[N], cnt[N][20], down[N][20];
vector < int > b[502], g[N];
void dfs(int v){
tin[v] = ++tick, pos[tick] = v;
for(int u : g[v]) dfs(u);
tout[v] = tick;
}
void dfs2(int v, int tp){
if((tin[v] + B - 1) / B != tp) down[tp][a[v]]++;
for(int u : g[v]) dfs2(u, tp);
}
void solve(){
cin >> n >> m >> q >> a[1];
for(int i = 2; i <= n; i++) cin >> p[i] >> a[i], g[p[i]].push_back(i);
dfs(1);
for(int i = 1; i <= n; i++) b[(i + B - 1) / B].push_back(pos[i]), cnt[(i + B - 1) / B][a[pos[i]]]++;
for(int i = 1; i <= (n + B - 1) / B; i++) dfs2(pos[(i - 1) * B + 1], i);
while(q--){
int r1, r2;
cin >> r1 >> r2, k = 0;
for(int i = 1; i <= (n + B - 1) / B; i++) k += cnt[i][r1] * 1ll * down[i][r2];
cout << k << endl;
}
}
signed main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
int tt = 1;
// cin >> tt;
while(tt--) solve();
}
