#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
#define ALL(v) (v).begin(), (v).end()
#define MASK(i) (1LL << (i))
#define GETBIT(mask, i) (((mask) >> (i)) & 1)
// mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
mt19937_64 rng(1);
ll rngesus(ll l, ll r){return ((ull) rng()) % (r - l + 1) + l;}
ll max(ll a, ll b){return (a > b) ? a : b;}
ll min(ll a, ll b){return (a < b) ? a : b;}
ll LASTBIT(ll mask){return mask & (-mask);}
ll pop_cnt(ll mask){return __builtin_popcountll(mask);}
ll ctz(ll mask){return __builtin_ctzll(mask);}
ll clz(ll mask){return __builtin_clzll(mask);}
ll logOf(ll mask){return 63 - clz(mask);}
template <class T1, class T2>
bool minimize(T1 &a, T2 b){
if (a > b){a = b; return true;}
return false;
}
template <class T1, class T2>
bool maximize(T1 &a, T2 b){
if (a < b){a = b; return true;}
return false;
}
template <class T>
void printArr(T& a, string separator = " ", string finish = "\n"){
for(auto i: a) cout << i << separator;
cout << finish;
}
template <class T>
void remove_dup(vector<T> &a){
sort(ALL(a));
a.resize(unique(ALL(a)) - a.begin());
}
const int N = 2e5 + 69;
int n, R, q;
vector<int> graph[N];
int region[N];
int l[N], r[N];
int dfs_cnt = 0;
void dfs(int u){
l[u] = r[u] = ++dfs_cnt;
for(int v: graph[u]){
dfs(v);
r[u] = r[v];
}
}
vector<int> in[N], out[N];
int main(void){
ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
cin >> n >> R >> q;
cin >> region[1];
for(int i = 2; i<=n; ++i){
int j;
cin >> j >> region[i];
graph[j].push_back(i);
}
dfs(1);
for(int i= 1; i<=n; ++i){
in[region[i]].push_back(l[i]);
out[region[i]].push_back(r[i]);
}
for(int i = 1; i<=R; ++i){
sort(ALL(in[i]));
sort(ALL(out[i]));
}
cout << endl;
map<pair<int, int>, int> mp;
while(q--){
int r1, r2; cin >> r1 >> r2;
pair<int, int> cur = {r1, r2};
if (mp.count(cur)) {cout << mp[cur] << endl << endl; continue;}
ll ans = 0;
if (in[r1].size() <= in[r2].size()){
for(int i: in[r1]) {
ans -= lower_bound(ALL(in[r2]), i) - in[r2].begin();
}
for(int i: out[r1]) {
ans += upper_bound(ALL(in[r2]), i) - in[r2].begin();
}
}
else{
// printArr(in[r1]); printArr(out[r1]);
// printArr(in[r2]); printArr(out[r2]);
for(int i: in[r2]){
ans -= (lower_bound(ALL(out[r1]), i) - out[r1].begin()) - (upper_bound(ALL(in[r1]), i) - in[r1].begin());
}
}
cout << ans << endl << endl;
mp[cur] = ans;
}
return 0;
}
