#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
#include <bits/stdc++.h>
using namespace std;
#define for_(i, s, e) for (int i = s; i < (int) e; i++)
#define for__(i, s, e) for (ll i = s; i < e; i++)
typedef long long ll;
typedef vector<int> vi;
typedef pair<int, int> ii;
//#define endl '\n'
struct pair_hash
{
template <class T1, class T2>
std::size_t operator() (const std::pair<T1, T2> &pair) const
{
return std::hash<T1>()(pair.first) ^ std::hash<T2>()(pair.second);
}
};
const int MXN = 200000, MXR = 25000, INF = 1e9+1;
int n, r, q;
int reg[MXN+1], tin[MXN+1], tout[MXN+1], pt = 0;
vi adj[MXN+1];
vector<vi> regList[MXR+1];
unordered_map<ii, int, pair_hash> seen;
void dfs(int p, int parent) {
regList[reg[p]].push_back({pt, p});
tin[p] = pt++;
for (int i: adj[p]) if (i != parent) dfs(i, p);
tout[p] = pt-1;
}
int main() {
#ifdef shiven
freopen("test.in", "r", stdin);
#endif
ios_base::sync_with_stdio(false);
cin.tie(0);
cin >> n >> r >> q;
cin >> reg[0];
reg[0] -= 1;
seen.reserve(MXR*10);
for_(i, 1, n) {
int p; cin >> p >> reg[i];
reg[i] -= 1;
adj[p-1].push_back(i);
}
dfs(0, 0);
while (q--) {
int r1, r2; cin >> r1 >> r2;
r1 -= 1; r2 -= 1;
if (seen.find({r1, r2}) != seen.end()) {
cout << seen[{r1, r2}] << endl;
continue;
}
//cout << r1 << " " << r2 << endl;
int ans = 0;
for (auto i: regList[r1]) {
auto pta = lower_bound(regList[r2].begin(), regList[r2].end(), (vi) {tin[i[1]]+1, -1});
auto ptb = upper_bound(regList[r2].begin(), regList[r2].end(), (vi) {tout[i[1]], INF});
//cout << ptb-pta << endl;
ans += ptb-pta;
}
cout << ans << endl;
seen[{r1, r2}] = ans;
}
return 0;
}
