#include <bits/stdc++.h>
using namespace std;
const int N = 2e5+10, BLOCK = 500, MR = 25010;
int n, R, Q, tin[N], tout[N], sz[N], re[N], cnt[MR], ti;
unordered_map<int, int> ans[MR]; //stores answer for big regions(precompute)
vector<int> lis[MR], G[N], ch[N]; //lis[i] denotes a list of those whose region is i sorted by tin[i]
inline void add(int p, int u){
ch[p].emplace_back(u);
cnt[re[u]]++;
}
inline bool isbig(int r){
return ((int)lis[r].size() > BLOCK);
}
inline bool isAnc(int p, int u){
return (tin[p] <= tin[u] and tout[u] <= tout[p]);
}
void dfs1(int u){
sz[u] = 1;
lis[re[u]].emplace_back(u);
tin[u] = ++ti;
for(int v : G[u]) dfs1(v), sz[u] += sz[v];
tout[u] = ti;
}
void dfs2(int u, bool keep){
int bc = -1;
for(int v : G[u]) if(bc == -1 or sz[v] > sz[bc]) bc = v;
for(int v : G[u]) if(v != bc) dfs2(v, 0);
if(bc != -1){
dfs2(bc, 1);
swap(ch[bc], ch[u]);
}
add(u, u);
for(int v : G[u]){
if(v == bc) continue;
for(int vv : ch[v]){
add(u, vv);
}
}
if(isbig(re[u])){
for(int r = 1; r <= R; r++){
ans[re[u]][r] += cnt[r];
}
}
if(keep == 0){
for(int v : ch[u]) cnt[re[v]]--;
}
}
int getans(int r1, int r2){
int b = 0, s = 0, res = 0;
stack<int> st;
while(b < lis[r1].size() or s < lis[r2].size()){
if((b < lis[r1].size()) and (s == lis[r2].size() or tin[lis[r1][b]] < tin[lis[r2][s]])){
while(!st.empty() and !isAnc(st.top(), lis[r1][b])) st.pop();
st.push(lis[r1][b]);
b++;
} else {
while(!st.empty() and !isAnc(st.top(), lis[r2][s])) st.pop();
res += st.size();
s++;
}
}
return res;
}
int main(void){
ios_base::sync_with_stdio(0); cin.tie(0);
cin >> n >> R >> Q;
cin >> re[1];
for(int i = 2; i <= n; i++){
int p; cin >> p >> re[i];
G[p].emplace_back(i);
}
dfs1(1);
dfs2(1, 1);
while(Q--){
int r1, r2; cin >> r1 >> r2;
if(isbig(r1) or isbig(r2)){
cout << ans[r1][r2] << endl;
} else {
cout << getans(r1, r2) << endl;
}
}
return 0;
}
