#include <bits/stdc++.h>
#define lsb(x) (x & (-x))
#define ll long long
#define ull unsigned long long
#if 0
const int MOD = ;
inline int lgput(int a, int b) {
int ans = 1;
while(b > 0) {
if(b & 1) ans = (1LL * ans * a) % MOD;
b >>= 1;
a = (1LL * a * a) % MOD;
}
return ans;
}
inline void mod(int &x) {
if(x >= MOD)
x -= MOD;
}
inline void add(int &x, int y) {
x += y;
mod(x);
}
inline void sub(int &x, int y) {
x += MOD - y;
mod(x);
}
inline void mul(int &x, int y) {
x = (1LL * x * y) % MOD;
}
inline int inv(int x) {
return lgput(x, MOD - 2);
}
#endif
#if 0
int fact[], invfact[];
inline void prec(int n) {
fact[0] = 1;
for(int i = 1; i <= n; i++) {
fact[i] = (1LL * fact[i - 1] * i) % MOD;
}
invfact[n] = lgput(fact[n], MOD - 2);
for(int i = n - 1; i >= 0; i--) {
invfact[i] = (1LL * invfact[i + 1] * (i + 1)) % MOD;
}
}
inline int comb(int n, int k) {
if(n < k) return 0;
return (1LL * fact[n] * (1LL * invfact[k] * invfact[n - k] % MOD)) % MOD;
}
#endif
using namespace std;
const int MAXN = (int) 2e5;
const int MAXR = 25000;
const int B = 700;
vector <int> g[MAXN + 1];
int id[MAXN + 1], fr[MAXR + 1];
vector <int> in[MAXR + 1], out[MAXR + 1];
int sz;
void dfs(int nod) {
in[id[nod]].push_back(++sz);
for(auto it : g[nod]) {
dfs(it);
}
out[id[nod]].push_back(sz);
}
int where[MAXR + 1], vals[MAXN + 1];
ll cnt1[MAXN / B][MAXR + 1];
void dfs1(int nod, int num) {
for(int i = 0; i < num; i++) {
cnt1[i][id[nod]] += fr[vals[i]];
}
fr[id[nod]]++;
for(auto it : g[nod]) {
dfs1(it, num);
}
fr[id[nod]]--;
}
ll cnt2[MAXN / B][MAXR + 1];
int w[MAXN + 1];
void dfs2(int nod, int cur) {
w[nod] = 0;
for(auto it : g[nod]) {
dfs2(it, cur);
w[nod] += w[it];
}
cnt2[cur][id[nod]] += w[nod];
w[nod] += (where[id[nod]] == cur);
}
int main() {
#if 0
ifstream cin("A.in");
ofstream cout("A.out");
#endif
int i, n, r, q;
ios::sync_with_stdio(false);
cin.tie(0), cout.tie(0);
cin >> n >> r >> q;
cin >> id[1];
for(i = 2; i <= n; i++) {
int par;
cin >> par >> id[i];
g[par].push_back(i);
}
for(i = 1; i <= n; i++) {
fr[id[i]]++;
}
dfs(1);
int num = 0;
for(i = 1; i <= r; i++) {
if(fr[i] >= B) {
vals[num] = i;
where[i] = num++;
}
}
fill(fr, fr + MAXR + 1, 0);
dfs1(1, num);
for(i = 0; i < num; i++) {
dfs2(1, i);
}
while(q--) {
int r1, r2;
cin >> r1 >> r2;
ll ans = 0;
if(fr[r1] < B && fr[r2] < B) {
int sz = in[r2].size();
int p = 0;
for(auto it : in[r1]) {
while(p < sz && in[r2][p] <= it) p++;
ans -= p;
}
p = 0;
for(auto it : out[r1]) {
while(p < sz && in[r2][p] <= it) p++;
ans += p;
}
}
else {
ans = (fr[r1] >= B ? cnt1[where[r1]][r2] : cnt2[where[r2]][r1]);
}
cout << ans << "\n";
cout.flush();
}
return 0;
}
