| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 677810 | Baytoro | Regions (IOI09_regions) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
using namespace std;
#define ios ios::sync_with_stdio(false); cin.tie(NULL);cout.tie(NULL);
#define pb push_back
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define fr first
#define sc second
//#define int long long
#define endl '\n'
void fopn(string name){
freopen((name+".in").c_str(),"r",stdin);
freopen((name+".out").c_str(),"w",stdout);
}
const long long INF=1e18,mod=998244353;
int n,r,q;
const int N=2e5+5,block=25005;
int a[N],st[N],ed[N],B[N],used[block];
vector<int> g[N],e[block];
int cnt=1;
unordered_map<int,int> clc[block];
void dfs(int x){
st[x]=cnt++;
for(auto it: g[x]){
dfs(it);
}
ed[x]=cnt-1;
}
void solve(){
cin>>n>>r>>q>>a[1];
for(int i=2;i<=n;i++){
int x;cin>>x>>a[i];
g[x].pb(i);
}
int b=sqrt(n);
dfs(1);
for(int i=1;i<=n;i++) B[st[i]]=i;
for(int i=1;i<=n;i++) e[a[B[i]]].pb(st[B[i]]);
for(int i=1;i<=n;i++){
if(used[a[B[i]]]) continue;
if((int)e[a[B[i]]].size()<=b) continue;
used[a[B[i]]]=1;
vector<int> pref(n+2);
for(auto it: e[a[B[i]]]){
int l=st[B[it]],r=ed[B[it]];
pref[l]++;
pref[r+1]--;
}
for(int j=1;j<=n;j++){
pref[j]+=pref[j-1];
clc[a[B[j]]][a[B[i]]]+=pref[j];
}
}
while(q--){
int a,b;cin>>a>>b;int ans=0;
if((int)e[a].size()<=b){
for(auto it: e[a]){
int l=st[B[it]],r=ed[B[it]];
auto i1=upper_bound(all(e[b]),r)-e[b].begin();
auto i2=upper_bound(all(e[b]),l)-e[b].begin();
if(i1){
i1--;
ans+=max((int)i1-i2+1,0ll);
}
}
}
else
ans=clc[b][a];
cout<<ans<<endl;
}
}
main(){
//fopn("newbarn");
//ios;
int T=1;
//cin>>T;
while(T--){
solve();
}
}