Submission #713287

#	Time	Username	Problem	Language	Result	Execution time	Memory
713287		amirhoseinfar1385	Birthday gift (IZhO18_treearray)	C++17	100 / 100	1290 ms	77700 KiB

treearray

#include<bits/stdc++.h>
using namespace std;
int n,m,q;
const int maxn=200000+10;
vector<int>adj[maxn];
int timea=0;
pair<int,int>stf[maxn];
int lca[19][maxn];
 
void dfs(int u,int par=0){
	timea++;
	stf[u].first=timea;
	lca[0][u]=par;
	for(auto x:adj[u]){
		if(x==par){
			continue;
		}
		dfs(x,u);
	}
	stf[u].second=timea;
}
 
void callca(){
	for(int i=1;i<19;i++){
		for(int j=1;j<=n;j++){
			lca[i][j]=lca[i-1][lca[i-1][j]];
		}
	}
}
 
bool zird(int u,int v){
	if(stf[v].first<=stf[u].first&&stf[v].second>=stf[u].second){
		return 1;
	}
	return 0;
}
 
int getlca(int u,int v){
	if(zird(u,v)){
		return v;
	}
	if(zird(v,u)){
		return u;
	}
	for(int i=18;i>=0;i--){
		if(lca[i][u]!=0&&!zird(v,lca[i][u])){
			u=lca[i][u];
		}
	}
	u=lca[0][u];
	return u;
}
set<pair<int,int>>st[maxn];
int main(){
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	cin>>n>>m>>q;
	for(int i=0;i<n-1;i++){
		int u,v;
		cin>>u>>v;
		adj[u].push_back(v);
		adj[v].push_back(u);
	}
	dfs(1);
	callca();
	vector<int>allm(m);
	for(int i=0;i<m;i++){
		cin>>allm[i];
	}
	for(int i=0;i<m;i++){
		st[allm[i]].insert(make_pair(i,i));
		if(i!=m-1){
			st[getlca(allm[i],allm[i+1])].insert(make_pair(i,i+1));
		}
	}
	for(int i=0;i<q;i++){
		int qq;
		cin>>qq;
		if(qq==1){
			int ind,v;
			cin>>ind>>v;
			ind--;
			st[allm[ind]].erase(make_pair(ind,ind));
			if(ind!=m-1){
				st[getlca(allm[ind],allm[ind+1])].erase(make_pair(ind,ind+1));
			}
			if(ind!=0){
				st[getlca(allm[ind],allm[ind-1])].erase(make_pair(ind-1,ind));
			}
			allm[ind]=v;
			st[allm[ind]].insert(make_pair(ind,ind));
			if(ind!=m-1){
				st[getlca(allm[ind],allm[ind+1])].insert(make_pair(ind,ind+1));
			}
			if(ind!=0){
				st[getlca(allm[ind],allm[ind-1])].insert(make_pair(ind-1,ind));
			}
		}
		else{
			int l,r,v;
			cin>>l>>r>>v;
			l--;
			r--;
			auto xx=st[v].lower_bound(make_pair(l,0));
			if(xx==st[v].end()){
				cout<<-1<<" "<<-1<<"\n";
				continue;
			}
			auto x=*xx;
			if(x.second<=r){
				cout<<x.first+1<<" "<<x.second+1<<"\n";
			}
			else{
				cout<<-1<<" "<<-1<<"\n";
			}
		}
	}
}

• Subtask 1: 12 / 12
• Subtask 2: 18 / 18
• Subtask 3: 26 / 26
• Subtask 4: 44 / 44