#include <bits/stdc++.h>
using namespace std;
int num = 0;
vector<int> o;
void dfs(int curr, int par, vector<int>& reg, vector<vector<int>>& orr, vector<int>& dfs_num, vector<int>& ss, vector<vector<int>>& adj) {
dfs_num[curr] = num;
num++;
orr[reg[curr]].push_back(curr);
o.push_back(curr);
for (int neigh : adj[curr]) {
if (neigh != par) {
dfs(neigh, curr, reg, orr, dfs_num, ss, adj);
ss[curr] += ss[neigh];
}
}
}
int main()
{
int n, r, q;
cin >> n >> r >> q;
vector<int> reg(n);
cin >> reg[0];
reg[0]--;
vector<vector<int>> adj(n);
vector<int> par(n);
par[0] = -1;
for (int i = 1; i < n; i++) {
cin >> par[i] >> reg[i];
par[i]--; reg[i]--;
adj[i].push_back(par[i]);
adj[par[i]].push_back(i);
}
vector<int> dfs_num(n);
vector<int> ss(n, 1);
vector<vector<int>> orr(r);
dfs(0, 0, reg, orr, dfs_num, ss, adj);
vector<vector<int>> pre1(n);
vector<vector<int>> pre2(n);
int sq = sqrt(n);
for (int i = 0; i < r; i++) {
if ((int) orr[i].size() >= sq) {
pre1[i].assign(r, 0);
vector<int> dp1(n, 0);
for (int j = 0; j < n; j++) {
if (reg[o[j]] == i) dp1[j]++;
if (j != 0) dp1[j] += dp1[dfs_num[par[o[j]]]];
pre1[i][reg[o[j]]] += dp1[j];
}
pre2[i].assign(r, 0);
vector<int> dp2(n, 0);
for (int j = n-1; j >= 0; j--) {
pre2[i][reg[o[j]]] += dp2[j];
if (j != 0) {
if (reg[o[j]] == i) dp2[j]++;
dp2[dfs_num[par[o[j]]]] += dp2[j];
}
}
}
}
for (int i = 0; i < q; i++) {
int r1, r2;
cin >> r1 >> r2;
r1--; r2--;
if ((int) orr[r1].size() >= sq) cout << pre1[r1][r2] << endl;
else if ((int) orr[r2].size() >= sq) cout << pre2[r2][r1] << endl;
else {
int sum = 0;
stack<int> s;
int i1 = 0;
int i2 = 0;
while (i2 < (int) orr[r2].size()) {
if (i1 >= (int) orr[r1].size() || dfs_num[orr[r2][i2]] > dfs_num[orr[r1][i1]]) {
while (!s.empty() && dfs_num[orr[r2][i2]] >= dfs_num[s.top()] + ss[s.top()]) s.pop();
sum += (int) s.size();
i2++;
} else {
s.push(orr[r1][i1]);
i1++;
}
}
cout << sum << endl;
}
}
return 0;
}
