#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
#include "deb.h"
#else
#define debug(...)
#endif
const int B = 450;
void solve() {
int n, r, q;
cin >> n >> r >> q;
vector<int> p(n), region(n);
cin >> region[0];
--region[0];
vector<vector<int>> employees(r), g(n);
employees[region[0]].push_back(0);
for (int i = 1; i < n; i++) {
cin >> p[i] >> region[i];
--p[i]; --region[i];
employees[region[i]].push_back(i);
g[p[i]].push_back(i);
g[i].push_back(p[i]);
}
vector<int> big;
vector<int> index(r, -1);
for (int i = 0; i < r; i++) {
if (employees[i].size() >= B) {
index[i] = big.size();
big.push_back(i);
}
}
vector<vector<long long>> prec(big.size(), vector<long long>(big.size()));
vector<int> freq(big.size());
vector<vector<long long>> anc(n, vector<long long>(big.size()));
auto Fill = [&](auto&& self, int v, int pr) -> void {
if (index[region[v]] != -1) {
for (int j = 0; j < big.size(); j++) {
prec[j][index[region[v]]] += freq[j];
}
++freq[index[region[v]]];
}
for (int j = 0; j < big.size(); j++) {
anc[v][j] += freq[j];
}
for (int u : g[v]) {
if (u != pr) {
self(self, u, v);
}
}
if (index[region[v]] != -1) {
--freq[index[region[v]]];
}
};
Fill(Fill, 0, -1);
vector<int> tin(n), tout(n);
int timer = 0;
auto Dfs = [&](auto&& self, int v, int pr) -> void {
tin[v] = timer++;
for (int u : g[v]) {
if (u != pr) {
self(self, u, v);
}
}
tout[v] = timer;
};
Dfs(Dfs, 0, -1);
vector<vector<int>> at(r, {-1});
for (int i = 0; i < n; i++) {
at[region[i]].push_back(tin[i]);
}
for (int i = 0; i < r; i++) {
sort(at[i].begin(), at[i].end());
at[i].push_back(n);
}
auto in_subtree = [&](int k, int v) {
int l = tin[v], r = tout[v];
return lower_bound(at[k].begin(), at[k].end(), r) - lower_bound(at[k].begin(), at[k].end(), l);
};
while (q--) {
int r1, r2;
cin >> r1 >> r2;
--r1; --r2;
if (employees[r1].size() >= B) {
if (employees[r2].size() >= B) {
cout << prec[index[r1]][index[r2]] << '\n';
continue;
} else {
long long ans = 0;
for (int e : employees[r2]) {
ans += anc[e][index[r1]];
}
cout << ans << '\n';
continue;
}
}
long long ans = 0;
for (int e : employees[r1]) {
ans += in_subtree(r2, e);
}
cout << ans << '\n';
fflush(stdout);
}
}
int main() {
int t = 1;
// cin >> t;
while (t--) {
solve();
}
return 0;
}
