#include <bits/stdc++.h>
using namespace std;
#define int long long
const int MAXN = 2e5 + 10;
const int SQRT = 512;
vector<int> adj[MAXN];
int n, r, q;
int cnt[SQRT];
int tot[SQRT][SQRT], reg[MAXN], sup[MAXN];
int id_large[MAXN];
vector <int> large;
vector<int> pos[MAXN], vals[MAXN], pos2[MAXN];
int tin[MAXN], tout[MAXN], tcur;
void dfs_sub_1(int v) {
int rid = id_large[reg[v]];
if (rid) {
for (int i = 1; i < (int) large.size(); i++) {
tot[i][rid] += cnt[i];
}
cnt[rid]++;
}
for (int w: adj[v]) {
dfs_sub_1(w);
}
if (rid) {
cnt[rid]--;
}
}
void dfs_sub_2(int v) {
tin[v] = ++tcur;
pos[reg[v]].push_back(tin[v]);
vals[reg[v]].push_back(v);
for (int w: adj[v]) {
dfs_sub_2(w);
}
tout[v] = tcur;
pos2[reg[v]].push_back(tout[v]);
}
int query(int l, int r, int x) {
auto it_l = lower_bound(pos[x].begin(), pos[x].end(), l);
auto it_r = upper_bound(pos[x].begin(), pos[x].end(), r);
return it_r - it_l;
}
int query_inv(int i, int x) {
int it_l = upper_bound(pos[x].begin(), pos[x].end(), i) - pos[x].begin();
int it_r = lower_bound(pos2[x].begin(), pos2[x].end(), i) - pos2[x].begin();
return it_l - it_r;
}
void solve() {
large.push_back(0);
cin >> n >> r >> q;
cin >> reg[1];
for (int i = 2; i <= n; i++) {
cin >> sup[i] >> reg[i];
adj[sup[i]].push_back(i);
}
dfs_sub_2(1);
for (int i = 1; i <= r; i++) {
sort(pos2[i].begin(), pos2[i].end());
}
for (int i = 1; i <= r; i++) {
if ((int) vals[i].size() > 500) {
id_large[i] = large.size();
large.push_back(i);
}
}
dfs_sub_1(1);
while (q--) {
int x, y;
cin >> x >> y;
int resp = 0;
if (!id_large[x]) {
for (int v: vals[x]) {
resp += query(tin[v], tout[v], y);
}
} else if (!id_large[y]) {
for (int v: vals[y]) {
resp += query_inv(tin[v], x);
}
} else {
resp = tot[id_large[x]][id_large[y]];
}
cout << resp << endl;
}
}
int32_t main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
solve();
return 0;
}
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