#include <iostream>
#include <vector>
#include <map>
#include <tuple>
#include <algorithm>
using namespace std;
const int SQRT = 450;
int n, r, q, region[200005], in[200005], out[200005], idx;
vector<int> adj[200005], blocks[25005], dfsorder, pref;
map<pair<int, int>, int> ans;
void dfs(int curr, int par) {
in[curr] = ++idx;
blocks[region[curr]].push_back(idx);
dfsorder.push_back(curr);
for (int i : adj[curr]) {
if (i == par) continue;
dfs(i, curr);
}
out[curr] = idx;
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
cin >> n >> r >> q >> region[1];
for (int i = 2, x; i <= n; i++) {
cin >> x >> region[i];
adj[x].push_back(i);
adj[i].push_back(x);
}
idx = -1;
dfs(1, -1);
for (int i = 1; i <= r; i++) {
if (blocks[i].size() >= SQRT) {
pref.resize(idx + 5, 0);
for (int j : blocks[i]) {
pref[j]++;
pref[out[dfsorder[j]] + 1]--;
}
for (int j = 1; j <= idx; j++) {
pref[j] += pref[j - 1];
ans[{i, region[dfsorder[j]]}] += pref[j];
}
}
}
for (int i = 0, r1, r2, ret; i < q; i++) {
cin >> r1 >> r2;
if (blocks[r1].size() >= SQRT) {
cout << ans[{r1, r2}] << "\n" << flush;
} else {
ret = 0;
for (int j : blocks[r1]) {
ret += upper_bound(blocks[r2].begin(), blocks[r2].end(), out[dfsorder[j]]) - upper_bound(blocks[r2].begin(), blocks[r2].end(), j);
}
cout << ret << "\n" << flush;
}
}
}
