Submission #967907

# Submission time Handle Problem Language Result Execution time Memory
967907 2024-04-23T04:59:55 Z 8pete8 Regions (IOI09_regions) C++17
100 / 100
3858 ms 109220 KB
#include<iostream>
#include<stack>
#include<map>
#include<vector>
#include<string>
#include<unordered_map>
#include <queue>
#include<cstring>
#include<limits.h>
#include <cassert>
#include<cmath>
#include<set>
#include<algorithm>
#include <iomanip>
#include<numeric> //gcd(a,b)
#include<bitset>
#include <cstdlib> 
#include <cstdint>
using namespace std;
#define ll long long
#define f first
//#define endl "\n"
#define s second
#define pii pair<int,int>
#define ppii pair<int,pii>
#define vi vector<int>
#define pb push_back
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define F(n) for(int i=0;i<n;i++)
#define lb lower_bound
#define ub upper_bound
#define fastio ios::sync_with_stdio(false);cin.tie(NULL);
#pragma GCC optimize ("03,unroll-loops")
using namespace std;
//#define int long long
//#define double long double
const int mod=1e9+7,mxn=2e5+5,lg=60,inf=1e9,minf=-1e9,mx=3e4;
int root=700,st;
vector<int>adj[mxn+10];
int re[mxn+10],recnt[mxn+10],sz[mxn+10],hvyp[mxn+10],up[mxn+10];
int tin[mxn+10],tout[mxn+10],T=0;
void getsz(int cur){sz[cur]=1;for(auto i:adj[cur])getsz(i),sz[cur]+=sz[i];}
void dfs(int cur,int hvypa){
	tin[cur]=++T;
	int hvy=0;
	hvyp[cur]=hvypa;
	for(auto i:adj[cur]){
		if(sz[i]>sz[hvy])hvy=i;
		up[i]=cur;
	}
	for(auto i:adj[cur])if(i!=hvy)dfs(i,i);
	if(hvy)dfs(hvy,hvypa);
	tout[cur]=T;
}
bool cmp(int a,int b){return tin[a]<tin[b];}
struct chain{
	vector<int>have,com;
	vector<vector<int>>pos;
	void init(){
		if(have.empty())return;
		for(auto i:have)com.pb(re[i]);
		sort(all(com));
		sort(all(have),cmp);
		com.erase(unique(all(com)),com.end());
		pos.resize(com.size());
		for(auto i:have)pos[lb(all(com),re[i])-com.begin()].pb(tin[i]);
		return;
	}
	int get(int x,int id){
		auto it=lb(all(com),id)-com.begin();
		if(it>=pos.size()||com[it]!=id)return 0;
		if(pos[it].empty())return 0;
		if(pos[it].back()<=x)return pos[it].size();
		else return upper_bound(all(pos[it]),x)-pos[it].begin();
	}
}t[mxn+10];//parent of hvy chain
vector<int>pos[mxn+10];
vector<int>have[mxn+10];
int pre[mx][500];
int32_t main(){
	fastio
	int n,r,q;cin>>n>>r>>q;	
	root=sqrt(n);
	for(int i=1;i<=n;i++){
		if(i!=1){
			int b;cin>>b;
			adj[b].pb(i);
		}
		cin>>re[i];
		recnt[re[i]]++;
		have[re[i]].pb(i);
	}
	getsz(1);
	dfs(1,1);
	for(int i=1;i<=n;i++)t[hvyp[i]].have.pb(i);
	for(int i=1;i<=n;i++)t[i].init(),pos[re[i]].pb(tin[i]);
	for(int i=1;i<=r;i++)sort(all(pos[i]));
	vector<int>k;
	for(int i=1;i<=r;i++){
		if(recnt[i]<root)continue;
		k.pb(i);
	}
	for(int i=1;i<=n;i++){
		int cur=i;
		while(hvyp[cur]!=1){
			for(int j=0;j<k.size();j++){
				pre[re[i]][j]+=t[hvyp[cur]].get(tin[cur],k[j]);
			}
			cur=up[hvyp[cur]];
		}
		for(int j=0;j<k.size();j++)pre[re[i]][j]+=t[hvyp[cur]].get(tin[cur],k[j]);
	}
	//qry r1,r2 cout<<pre[r2][pos r1];
	while(q--){
		int a,b;cin>>a>>b;
		if(recnt[a]<root){
			int ans=0;
			for(auto j:have[a]){
				int l=lb(all(pos[b]),tin[j])-pos[b].begin();
				if(l==pos[b].size())continue;
				int r=ub(all(pos[b]),tout[j])-pos[b].begin()-1;
				ans+=(r-l+1);
			}
			cout<<ans<<endl;
		}
		else{
			auto it=lb(all(k),a)-k.begin();
			cout<<pre[b][it]<<endl;
		}
	}
}
/*
sqrt decomp
if region cnt<=sqrtn -> burte force sqrtn{
	do euler tour keep vector of pos in euler tour for each region
	when qry r1,r2 loop through all sqrtn node then qry in subtree of that node
	qry-> bs l,r in vector of r2; ans+=(r-l+1)
}
else we precompute the region to other region (keep sqrtn(r)){
	use merge sort tree +hld? (too costly?){
		dont need merge sort?
		keep chain then each chain keep vector of pos for each region
	}

}
*/

Compilation message

regions.cpp: In member function 'int chain::get(int, int)':
regions.cpp:72:8: warning: comparison of integer expressions of different signedness: 'long int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   72 |   if(it>=pos.size()||com[it]!=id)return 0;
      |      ~~^~~~~~~~~~~~
regions.cpp: In function 'int32_t main()':
regions.cpp:107:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  107 |    for(int j=0;j<k.size();j++){
      |                ~^~~~~~~~~
regions.cpp:112:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  112 |   for(int j=0;j<k.size();j++)pre[re[i]][j]+=t[hvyp[cur]].get(tin[cur],k[j]);
      |               ~^~~~~~~~~
regions.cpp:121:9: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  121 |     if(l==pos[b].size())continue;
      |        ~^~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 8 ms 35160 KB Output is correct
2 Correct 8 ms 35160 KB Output is correct
3 Correct 8 ms 35160 KB Output is correct
4 Correct 10 ms 35160 KB Output is correct
5 Correct 12 ms 35140 KB Output is correct
6 Correct 15 ms 35160 KB Output is correct
7 Correct 20 ms 35160 KB Output is correct
8 Correct 25 ms 35416 KB Output is correct
9 Correct 38 ms 35672 KB Output is correct
10 Correct 55 ms 36184 KB Output is correct
11 Correct 80 ms 36688 KB Output is correct
12 Correct 99 ms 36996 KB Output is correct
13 Correct 136 ms 37976 KB Output is correct
14 Correct 222 ms 40704 KB Output is correct
15 Correct 222 ms 42308 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1518 ms 43624 KB Output is correct
2 Correct 1862 ms 46172 KB Output is correct
3 Correct 2314 ms 45224 KB Output is correct
4 Correct 186 ms 38504 KB Output is correct
5 Correct 225 ms 39252 KB Output is correct
6 Correct 547 ms 55668 KB Output is correct
7 Correct 1055 ms 63904 KB Output is correct
8 Correct 1070 ms 67204 KB Output is correct
9 Correct 1855 ms 51340 KB Output is correct
10 Correct 2836 ms 103500 KB Output is correct
11 Correct 3858 ms 59940 KB Output is correct
12 Correct 1166 ms 87160 KB Output is correct
13 Correct 1510 ms 87772 KB Output is correct
14 Correct 1953 ms 95840 KB Output is correct
15 Correct 2506 ms 104796 KB Output is correct
16 Correct 2284 ms 109220 KB Output is correct
17 Correct 2349 ms 98104 KB Output is correct