//#pragma GCC optimize("O3")
//#pragma GCC optimize("unroll-loops")
#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
template <class T>
using Tree =
tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
//#define int long long
#define ll long long
#define pii pair<int, int>
#define pll pair<ll, ll>
#define fi first
#define se second
#define rep(i, a, b) for (int i = a; i <= b; ++i)
#define per(i, b, a) for (int i = b; i >= a; --i)
#define pb push_back
#define eb emplace_back
#define all(v) (v).begin(), (v).end()
#define lsb(x) (x)&(-x)
void setIO(string name = "") {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);cout.tie(nullptr);
if (!name.empty()) {
freopen((name + ".in").c_str(), "r", stdin);
freopen((name + ".out").c_str(), "w", stdout);
}
}
ll fexp(ll a, ll b, ll m) {
if (b == 0) return 1LL;
ll p = a;
ll ans = 1;
while (b > 0) {
if (b % 2 != 0) ans = (ans*p)%m;
p = (p*p)%m;
b >>= 1;
}
return ans;
}
const int MAXN = 2e5 + 10;
//const int INF = 1e18+5;
const int MOD = 1e9+7;
vector<int> g[MAXN], id[25010],hi[510];
int ti[MAXN], to[MAXN], R[MAXN], dp[510][25000],bit[2*MAXN],q,n,r, t= 0;
// there can't be too many heavy groups!
map<int,int> mp;
void update(int i, int x) {
for (;i <= 2*n; i += lsb(i)) bit[i] += x;
}
int query(int i) {
int qq = 0;
for (; i > 0; i -= lsb(i)) qq += bit[i];
return qq;
}
void dfs(int u, int p = -1) {
ti[u] = t++;
for (const int &v : g[u]) {
if (v==p) continue;
dfs(v,u);
}
to[u] = t++;
}
void dfs2(int u, int m, int cur = 0, int p = -1) {
if (R[u] == m) hi[m].pb(ti[u]);
dp[m][R[u]] += cur;
for (const int &v : g[u]) {
if (v==p) continue;
dfs2(v,m, cur + (R[u]==m),u);
}
}
int HH(int a, int b) {
return dp[mp[a]][b];
}
int LL(int a, int b) {
for (auto &i: id[b]) update(to[i],1);
int ans = 0;
for (auto &i: id[a]) ans += query(to[i]) - query(ti[i]);
for (auto &i: id[b]) update(to[i],-1);
return ans;
}
int LH(int a, int b) {
cout << "OK!\n";
int ans = 0;
for (auto &i: id[a]) {
ans += (lower_bound(all(hi[mp[b]]), to[i]) - lower_bound(all(hi[mp[b]]), ti[i]) - 1);
}
return ans;
}
void solve() {
cin >> n >> r >> q;
cin >> R[1];
id[R[1]].pb(1);
rep(i,2,n) {
int pr,rg;cin >> pr >> rg;
R[i] = rg;
id[rg].pb(i);
g[i].pb(pr);
g[pr].pb(i);
}
dfs(1);
int cc = 1;
int HEAVY_THRESHOLD = 500;
rep(i,1,r) {
if (id[i].size() >HEAVY_THRESHOLD) {
mp[i] = cc++;
dfs2(1,mp[i]);
}
}
while (q--) {
int a,b;cin >> a >> b;
bool ha = id[R[a]].size() > HEAVY_THRESHOLD, hb = id[R[b]].size() > HEAVY_THRESHOLD;
int ans;
if (ha) ans = HH(a,b);
else if (hb) ans = LH(a,b);
else ans = LL(a,b);
cout << ans << endl;
cout << flush;
}
}
int32_t main() {
setIO();
int tt = 1;
//cin >> tt;
while (tt-- > 0) solve();
}
