#include "bits/stdc++.h"
#define ff first
#define ss second
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define sz(x) (int)(x).size()
using namespace std;
using ll = long long;
using pii = pair<int, int>;
const char nl = '\n';
const ll LINF = 0x3f3f3f3f3f3f3f3f;
const int INF = 0x3f3f3f3f;
int main() {
ios::sync_with_stdio(0), cin.tie(0);
int N, R, Q; cin >> N >> R >> Q;
vector<vector<int>> adj(N + 1);
vector<int> r(N + 1);
for (int i = 1; i <= N; i++) {
if (i == 1) {
int a; cin >> a;
r[i] = a;
} else {
int a, b; cin >> a >> b;
adj[a].push_back(i);
adj[i].push_back(a);
r[i] = b;
}
}
vector<vector<int>> emp(R + 1);
vector<int> tin(N + 1), tout(N + 1);
int tcur = 0;
auto euler = [&](auto euler, int x, int p) -> void {
tin[x] = ++tcur;
emp[r[x]].push_back(x);
for (int k : adj[x]) {
if (k == p) continue;
euler(euler, k, x);
}
tout[x] = tcur;
}; euler(euler, 1, -1);
while (Q--) {
int a, b; cin >> a >> b;
vector<pii> line;
for (int x : emp[a]) {
line.push_back({tin[x], 1});
line.push_back({tout[x], 3});
}
for (int y : emp[b])
line.push_back({tin[y], 2});
sort(all(line));
int ans = 0, cnt = 0;
for (auto [d, t] : line) {
if (t == 1) cnt++;
if (t == 2) ans += cnt;
if (t == 3) cnt--;
}
cout << ans << nl;
}
return 0;
}
