#include<bits/stdc++.h>
using namespace std;
#pragma GCC optimize ("Ofast")
#pragma GCC target ("avx,avx2,fma")
const int mxN = 4e5+5, mxR = 25005;
int reg[mxN], place[mxN], timer, st[mxN], en[mxN], pref[mxN];
vector<int> tr[mxN], inr[mxN], cans[mxN], pans[mxN], vis[mxN];
vector<pair<int,int>> rev[mxN];
vector<pair<int,int>> all;
const int bsz = 1024;
void euler(int x, int p) {
st[x] = ++timer;
place[timer] = reg[x];
for(auto it : tr[x]) if(it != p) euler(it, x);
en[x] = timer;
}
signed main() {
//freopen("regions.in", "r", stdin);
//freopen("regions.out", "w", stdout);
int N, R, Q; cin >> N >> R >> Q;
cin >> reg[1];
inr[reg[1]].push_back(1);
for(int i = 2; i <= N; i++) {
int s, h; cin >> s >> h;
reg[i] = h;
tr[s].push_back(i);
tr[i].push_back(s);
inr[h].push_back(i);
}
euler(1, -1);
for(int i = 1; i <= N; i++) all.push_back({st[i], i});
sort(all.begin(), all.end());
for(int r = 1; r <= R; r++) {
for(auto it : inr[r]) rev[r].push_back({st[it], 0}), rev[r].push_back({en[it]+1, 1}), vis[r].push_back(st[it]);
sort(rev[r].begin(), rev[r].end());
sort(vis[r].begin(), vis[r].end());
}
for(int r = 1; r <= R; r++) {
if(inr[r].size() > bsz) {
cans[r] = pans[r] = vector<int> (mxR);
for(int i = 0; i < mxN; i++) pref[i] = 0;
for(auto bad : vis[r]) pref[bad]++;
for(int i = 1; i < mxN; i++) pref[i] += pref[i-1];
#define get(l,r) (pref[(r)]-(((l)>0)?pref[(l)-1]:0))
for(int k = 1; k <= R; k++) {
if(k==r) continue;
for(auto member : inr[k]) cans[r][k] += get(st[member], en[member]);
}
int j = 0;
int active = 0;
for(int c = 1; c <= N; c++) {
while(j < int(rev[r].size()) && rev[r][j].first <= c) {
if(rev[r][j].second) active--; else active++;
j++;
}
pans[r][place[c]] += active;
}
}
}
for(int g = 1; g <= Q; g++) {
int a, b; cin >> a >> b;
if(inr[a].size() > bsz) {
cout << pans[a][b] << endl;
} else if(inr[b].size() > bsz) {
cout << cans[b][a] << endl;
} else {
int j = 0, active = 0, res = 0;
for(int ct : vis[b]) {
while(j < int(rev[a].size()) && rev[a][j].first <= ct) {
if(rev[a][j].second) active--; else active++;
j++;
}
res += active;
}
cout << res << endl;
}
}
}
