Submission #90095

#	Time	Username	Problem	Language	Result	Execution time	Memory
90095		nicksona	Birthday gift (IZhO18_treearray)	C++14	100 / 100	1818 ms	172592 KiB

treearray

#include<bits/stdc++.h>
#define ll long long
#define pb push_back
using namespace std;
int n,m,t;
int a,b;
vector <int> v[200001];
int par[200001][41];
int tin[200001],tout[200001];
int mas[200001];
int M=0;
set <int> s[200001];
set <int> s2[200001];
void go (int u,int p){
	par[u][0]=p;
	tin[u]=++M;
	for (int i=1;i<=30;i++){
		par[u][i]=par[par[u][i-1]][i-1];
	}
	
	for (int i=0;i<v[u].size();i++){
		int node=v[u][i];
		if (node!=p){
			go(node,u);
		}
	}
	tout[u]=++M;
}
bool is_par(int a,int b){
	if (tin[a]<=tin[b]&&tout[b]<=tout[a]){
		return true;
	}
	return false;
}
int lca (int a,int b){
	
	if (tin[a]>tin[b]){
		swap (a,b);
	}
	
	if (is_par(a,b)){
		return a;
	}
	
	if (is_par(b,a)){
		return b;
	}
	
	for (int i=30;i>=0;i--){
		if (par[a][i]!=0&&!is_par(par[a][i],b)){
			a=par[a][i];
		}
	}
	
	return par[a][0];
}
main () {
	ios::sync_with_stdio(false);
	//freopen ("damn.in","r",stdin);
	cin>>n>>m>>t;
	
	for (int i=1;i<n;i++){
		cin>>a>>b;
		v[a].pb(b);
		v[b].pb(a);
	}
 
	for (int i=1;i<=m;i++){
		cin>>mas[i];
	}	
	
	go (1,0);
	
	for (int i=1;i<m;i++){
		s[lca(mas[i],mas[i+1])].insert(i);
	}	
	
	for (int i=1;i<=m;i++){
		s2[mas[i]].insert(i);
	}	
	
	while (t--){
		int c;
		cin>>c;
		if (c==1){
			int x,y;
			cin>>x>>y;
			if (x!=1) s[lca(mas[x-1],mas[x])].erase(x-1);
			if (x!=m) s[lca(mas[x],mas[x+1])].erase(x);
			s2[mas[x]].erase(x);
			
			mas[x]=y;
			
			if (x!=1) s[lca(mas[x-1],mas[x])].insert(x-1);
			if (x!=m) s[lca(mas[x],mas[x+1])].insert(x);
			s2[mas[x]].insert(x);
		}
		else{
			int l,r,v2;
			cin>>l>>r>>v2;
			set<int>::iterator it,it2;
			it=s[v2].lower_bound(l);
			//cout<<"WOW"<<l<<" "<<r<<" "<<v<<endl;
			it2=s2[v2].lower_bound(l);
			int e;
			e=*it2;
			if (it2!=s2[v2].end()&&e<=r){
				cout<<e<<" "<<e<<endl;
				continue;
			}
			
			if (it!=s[v2].end()){
				e=*it;
				if (e<r){
					cout<<e<<" "<<e+1<<endl;
					continue;
				}
				else{
					cout<<-1<<" "<<-1<<endl;
					continue;
				}
			}
			cout<<-1<<" "<<-1<<endl;	
		}
	}
	return 0;
}
/*
  _   _   _          _
 | \ | | (_)        | |
 |  \| |  _    ___  | | __  ___    ___    _ __     __ _
 | . ` | | |  / __| | |/ / / __|  / _ \  | '_ \   / _` |
 | |\  | | | | (__  |   <  \__ \ | (_) | | | | | | (_| |
 |_| \_| |_|  \___| |_|\_\ |___/  \___/  |_| |_|  \__,_|
 
*/

Compilation message (stderr)

treearray.cpp: In function 'void go(int, int)':
treearray.cpp:21:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i=0;i<v[u].size();i++){
               ~^~~~~~~~~~~~
treearray.cpp: At global scope:
treearray.cpp:57:7: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main () {
       ^

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