#include <bits/stdc++.h>
using namespace std;
//#define int int64_t
#define rep(Begin,End) for (Begin=0;Begin<(End);Begin++)
#define all(x) x.begin(), x.end()
#define all1(x) x.rbegin(), x.rend()
#define sz(x) (int32_t)(x.size())
const int N = 3e5+4, mod =998244353;
const int64_t N1=1e18;
const double eps=1e-6,cmp=1e-3;
int tin[N],tout[N],c[N];
int tmr=1;
vector<int> adj[N];
vector<int> ctin[N],ctout[N],col[25001];
map<pair<int,int>,int> mp;
int euler[N];
void dfs(int u){
tin[u]=tmr;
euler[tmr]=c[u];
//cerr<<u<< " "<<c[u]<<"\n";
ctin[c[u]].push_back(tmr++);
col[c[u]].push_back(u);
for (const int& it:adj[u]){
dfs(it);
}
tout[u]=tmr++;
ctout[c[u]].push_back(tout[u]);
}
int child(int p,int chld){
int ans=0;
//cerr<<"chld";
for (const int& it:col[chld]){
//cerr<<it<<" ";
ans+=lower_bound(all(ctin[p]),tin[it])-ctin[p].begin();
ans-=upper_bound(all(ctout[p]),tin[it])-ctout[p].begin();
}
return ans;
}
int parent(int p,int chld){
int ans=0;
//cerr<<"gh";
//cout<<tin[1]<<" "<<tout[1]<<"\n";
for (const int& it:col[p]){
ans+=upper_bound(all(ctin[chld]),tout[it])-ctin[chld].begin();
ans-=upper_bound(all(ctin[chld]),tin[it])-ctin[chld].begin();
}
return ans;
}
void solve(){
int n,r,q;
cin>>n>>r>>q;
cin>>c[1];
for (int i=2,x,p;i<=n;i++){
cin>>p>>x;
c[i]=x;
adj[p].push_back(i);
}
dfs(1);
for (int i=1;i<=r;i++){
if (sz(col[i])>=400){
vector<int> ok(tmr+1);
for (const int& it:col[i]){
ok[tin[it]]++;
ok[tout[it]]--;
}
for (int j=1;j<tmr;j++){
ok[j]+=ok[j-1];
if (euler[j]){
mp[{i,euler[j]}]+=ok[j]-!!(euler[j]==i);
}
}
}
}
for (int r,r1;q;q--){
cin>>r>>r1;
if (sz(col[r])>=512){cout<<mp[{r,r1}]<<endl;continue;}
else{
int ans=0;
//cerr<<"gh";
//cout<<tin[1]<<" "<<tout[1]<<"\n";
int ans=0;
for (const int& it:col[r]){
ans+=upper_bound(all(ctin[r1]),tout[it])-ctin[r1].begin();
ans-=upper_bound(all(ctin[r1]),tin[it])-ctin[r1].begin();
}
cout<<ans<<endl;
}
}
}
int32_t main(){
ios::sync_with_stdio(false),cin.tie(nullptr),cout.tie(nullptr);
int tq = 1;
//cin>>tq;
for (;tq;tq--){solve();}
}
Compilation message
regions.cpp: In function 'void solve()':
regions.cpp:83:7: error: redeclaration of 'int ans'
83 | int ans=0;
| ^~~
regions.cpp:80:11: note: 'int ans' previously declared here
80 | int ans=0;
| ^~~
